A084 4-stroke engines - Print Topic

Here we go.
I bought this. I flew about 10 minutes with this plane and its a sheer joy. The sound of the engine is awesome. In my 30 years of flying never ever heard better sound.
Its weared out, the engine is ready for overhaul (but I have one I can swap within a day) but it still flyes well.

084 is definately a good option. Am I the second one on this board who ownes one ?

It came with a starter, the previous owner put a Skoda Favorit starter on it with a relative large flywheel. I dont know if this original or home made.
Cranks well. No carb heat box, but all intake tubes are insulated with foam and the carb is breathing from over the exhaust from the engine compartment.
I find no issue with the weight, it glides better than my 582 powered minimax.

On the 084 pretty much everything is as it came off from the original generator, and the prop is direct drive.
I cant tell you too much of a flight experience, I am straighten things out what the former owner disregarded. (loose rudder and tailwheel wires, wrong wheels e.t.c.
But even with abuse like this it flies very very well.

WOW that is really cool. I bet you could put it on u-tub so we could hear it go. :)

Nice looking Hi-Max! Sounds like the 084 is a good choice for them.

Thanks for the post pkoszegi !! Great pics! Looks like a nice airplane! I bet it does sound great!!

Thanks for posting this! I am very interested in this engine but wanted to see some good performance data behind it. After you fly it around a bit, could you let us know what your performance is like?

I would love to rebuild my own engine instead of just buying a hirth and hanging it up front, but would like to see some successes with it before I went that route.

Tom, I dont know what will happen to the valves, but the sound is really loud with no or with short exhaust pipe.
If you put short exhaust and no flywheel, no generator, no starter, no oil filter, you will end up just under 62 kgs 135 lb dry. Which is exactly the same as a 582 rotax with all bits and pieces. Its 13 kg more than a 503. and 18 kg more than a 2702.
The wonder is that it need no tuning, no changing carb, no nothing, but a hub at the front.

That exhaust underneath might save a few pounds but the sound of this engine, - mate , - I can tell you thats the music of the spheres. When the previous owner cranked the engine for two of us first time , we looked each other and said the same time: F.... THAT IS THE the sound... :)
Pictures taken from the replacement engine I bought from Bob, by Bob. Published by courtesy of Hoskins Engine Laboratories :) :) :)

Some prop info for the record:
Bob and Harless recommend 54x27 props from Tennessee props. According to my calculation I have a 59x20 inch currently on it flies well with it for years. Max static RPM is 2850 which is far from the ideal 3200-3300, but definately does not overspin the engine. I ve tested on the overhauled engine an other prop which is 55x22 which spins 2950 on that engine. This prop is designed for 447 trike with 2:58 redrive.
Just ideas what sort of props on direct drive makes a Himax fly.

Here we go with the 4a084 engine sound video.

https://www.youtube.com/watch?v=KjS_6tcvAuw&feature=youtu.be

More will come...

Yes that really sounds good. Thanks for letting us hear it. Blue sky's and tail winds to you. :)

That sure is a nice sounding motor!!! I want one too.

Quoted from TreeTopsTom

That sounds GREAT!!!! Way COOL!!!!
Plus as you said, The fact that it is possible to just put a hub adapter on it and it's ready to go!
I have heard those engines were build like , as they say, "a brick shit house".
Guess it's probably true. BUTTTTT
Has anyone torn one down after (X) hours to examine (measure) thrust bearing wear?
And would it really be a critical (instantaneous) issue or would there be plenty of warning of it's wearing out condition? Obviously these engines were meant to turn a pulley so I have to imagine there design did not take into consideration a constant (pulling forward) load. I would think this would be something to be aware of as the hours of use add up? yes? NO? I also imagine that a redrive would solve for that issue if you are skilled enough to fit one. (I know I'm not). But I think I would rather take my chances with that 4 stoker A084 out front than my 2 stroke Zenoah G-50. But the weight! Must make for a good dive bomber...LOL TTT

Tom, this engine is sound like hell as I saw it when I had my spare one completly overhauled.The work here cost around USD 400 + spare parts but they replace all bearings, piston, rings, rods and valves if needed. I paid USD 250 for the stainless steel exhaust.
The weight is not that serious. 125 lb is the weight of a 582. You may balance the difference of a 503 vs 084 with a good size of battery half way in the fuselage.
What I heard that these engines are there to run for 1000 hours + without any sort of problem over 3000 rpm constantly.
If thats true, this is the only engine which have a proven record of this.
The engine can provide 200lb of static thrust for sure (Bob has a video of 230 lb on a direct drive with 54x27 Tennessee prop). The Hirth 2702 provides about the same with 2.58 redrive, and 160 cm 3 blade composite prop. And look at my other video of my other Himax taking off and landing in 200 ft. Thats 20 kgs or 44 lb difference.
The engine with direct drive is really enough to power a Himax.
I am a lucky guy being only 73 kgs 170 cm tall (160lb 5.6 ft). So if you guys are around the same it should not be a problem. The problem would start with over 200 lb and over 6 feet people.

Well there is an option of a sincle cylinder two stroke 19 kg (45 lb) Pollini thor 250cc 36HP engine for EUR 4500. But is that what we are looking for ???

Just the low cost of the engine, overhaul, operation and the cheap wooden two blader prop makes sense for me. Not to mention the less than consumption of less than 2 Gal/h ?

Hi All & TTT;
Just for information. The A084 has a 1500 hour TBO. The center main bearing has a substantial thrust bearing. It can be thrust in both directions. This and the other Armed Service Standard Engines were manufactures to do almost anything, LOL and stay running at 3600 RPM doing it. Parts are still cheap, but will not last forever. Engines are getting more expensive because there were 3 million built and they are gone? Probably horders got them, LOL. All I can say is it is a darn good engine and it flys a Max very well. I have one ready to bolt right on my 1400, but that is now for sale.
Harless has flown the pants off his with over 500 hours on the engine and over 100 with my re-drive. Peter, get going, you have to catch up to Harless, LOL.
Bob

Hey Guys;
Talked to Harless this morning and I was wrong about the hours on his engine. He has over 300 hours on it not 500.
Bob

Today was wonderful, so I went to explore the new max. I did a few takeoff and landings. And a little x country.
Well, it needs a 150 m (450 ft roll) to rotate for takeoff, and with me it climbs 2 m/sec (400 ft/min). Its not a STOL for sure. Our grass strip is around 1500 Ft, its not particularly a challenge with that sort of runway. Landing could be done within 300 ft, it flares but not too much. Since I dont have tach I just feel that the maximum rpm is around 2850 and for cruising I guesstimate around 2600 for 110 km/h (70mph) . Best climb rate is around 85-90 km/h. The funny thing is that little over half power (guessing of 2200 rpm) it cruises 100 km/h (63 mph). It does 120-125km/h on full powerVery pleasant cruising in a non turbulent weather. Consumption goes around 2 GAL/h but I made several takeoff, climb, descend.
The oil stays on 65 C - 150 F, Cyl head on 150 C - 300F all the time. Looks very stable.

Landing is smooth, I dont feel it would want to dive like a rock, but the weight does definately takes its toll.
I have a glass fiber landing gear with a small tyre on it but its like a Cadillac. Very soft landings with no jumps. I think that the whole structure appreciates any sort of cushioning with such a weight involved in the gravity play.
I got some more props, tomorrow I will have some more testing with different props.
I would compare this to a loaded C172, maybe a C150 with two person and full fuel on board. Same feeling, you dont really want to get into very turbulent weather with that one either.

TTT
That is my engine in the pictures, but Harless's looks just like it. There are no CNC files for the re-drive. Both of them are "hand made", lol by me. A machinist, a dying breed today. I will help anybody that wants it. I have drawings of the parts for the re-drive, but it is complicated, LOL. There is a company somewhere out west that makes a re-drive for the 084 for about 8-9 hundred bucks. I have the link somewhere on this PC if interested. I have not flown behind a 084, but the one you see in the picture is ready to bolt to my Himax. It is a complete firewall forward. But I have the Himax up for sale now.
Harless is the guy to ask about performance. He is the "test facility", LOL. He is testing the engine and the re-drive. He has flown it straight drive and reduction. The ratio by the way is 1 to 1.666666666666666666666666. Sorry, LOL that is just the way it worked out. So, any questions about the engine and parts, ask me. Questions about the engine AND flying, ask Harless.
Also, don't forget Peter. He is going to have a "fleet" of Max's soon. He will be doing a lot of flying and prop tests with his. So there will be good info out there for the asking.
Bob

PSRU for the 084 can be bought at: http://www.arrowprop.com/rdrive.htm

That's the one Harless, thanks.
Bob

Tom:
I cross referenced some props with the overhauled engine (on the test bench) and the one in the plane which shows less compression. The top RPM of the prop differs only by 50 rpm or so which is not a lot. So the engine I have and have at least 180 hours in it, looks good as the new. It was told that it was new when the owner installed it. I doubt that though.
So just repeating : with 2850 static RPM it produces already enough power for takeoff on direct drive. Estimated 55x22 prop can get you good cruise, 450 ft to rotate takeoff.
Now if you want to invest into more weight and more parts to fail that is still a question for me too. Do you really want to pay for a redrive as much as your engine cost ?

Other important but not related to 084:   FUEL HOSE  issue:

I refuelled the aircraft yesterday, and I must admit I dont like the current setup for fuel tank. Its behind the seat, but a long thick tube goes up to wing level. When I fuel I dont see any sort of fuel level indication, so the fuel spilled into the cabin. Right onto the seat foams. It was soaked but the fuel did not go anywhere else so it can dry out.  Not a big deal just ruined my day for flying.  I took the seat out and look at the petrol tank first time. Down at the bottom where fuel line starts right on the tank output the petrol fuel line is melting like a chewing gum. So it was a nice accident to discover that.
I am sure that there is nothing wrong with the fuel rated hose, but more about ethanol what the govt allow in any fuel up to 5% without any notice to public.
Check your fuel lines in every 25 hours or so from the tank to the fuel pump because this is a regular problem. I had that with the other Himax too on the 2702 engine. After a winter, storaged in a dry cool place (hanger) last spring it showed cracks in the middle.
Or fuel rated hoses are not fuel rated anymore however its labelled like that.

TTT, I think you would be better off buying one from Arrowprop.. The one I have is second to none for quality and it also has an extra bearing in the center of the crank pulley to help keep the belt tension load off of the crank.. I would guess that if you get one made like mine, it would cost more than twice as much as the one from Arrowprop.. I don't know anything about the quality of the Arrowprop.. You might could call them and get to talk to someone that has one..

I would negotiate with Bob, I think it's freshly overhauled and has engine mounts already on it.

Hi Peter;
I strongly recommend you don't use any fuel with any amount of alcohol in it. They were designed and built in the 60's. there was no alcohol in any fuel back then. I don't know if the rubber products in the engine will take alcohol. The same with the fuel lines. VERY dangerous. They swell up and choke off the fuel flow, the first indication is just like you found, chewing gum. Here in the states, we have some gas stations that sell ethanol free gas. Sometimes it is premium. If all you can find is premium, advance the ignition a couple degrees to help compensate for the slower burning fuel. Remember to use Marvel Mystery oil. 2 oz/5 gal. Our auto gas has NO lead, so we have to lube the top end. Sorry for using a "brand" name here, but I have been using it with old design engines for 30 years and have not had top end problems.

Tom;
Lets see, where do I start? All my drawings are CAD drawings. No, I have not seen the other up close an touch it. Your local machine shop probably would not make it for you. He would know by looking at it he would have to charge you $4000.00 for it. It all comes down to hours. Harless and I are good friends, and you don't count hours when you help a friend. So, your machine shop would definitely be counting hours. If you check on re-drives, you will see that even the simple ones are $1,200.00 or more. So $700.00 seems to be a bargain to me.

Just a BIG note and warning here!!!!!!!!
These A084 engines you find for sale, are run out ready for overhaul. Read that again so you understand. The US Govt. fazed them out so all their equipment would run on the same fuel. A very smart move. So, as the engine ran up the time they removed them and put them up for auction. The only way to get one ready to run is buy an overhauled one from a trusted source, or buy a new one. Rebuilts and new are still available. NOW, when I say run out, I mean they are ready for new bearings rings possible valve work and so on. The cranks are hardened steel as with the cylinders. The Babbitt on the bearing shells has worn and any further running will destroy the cranks. Yup, good oil pressure, yup good compression, yup i destroyed my engine. If you buy one, just go ahead and buy the parts and overhaul it before you get in trouble 2500 feet up. The parts are dirt cheap, it would be silly not to make it good as new.
Bob

Tom;
I think you asked if I would sell my engine (A084). Since I am selling my Himax, I guess I would consider selling the engine. I will post it in the for sale section.
Bob

Quoted from Bob Hoskins

Hi Peter;
I strongly recommend you don't use any fuel with any amount of alcohol in it......... Sometimes it is premium. If all you can find is premium, advance the ignition a couple degrees to help compensate for the slower burning fuel. ...........Sorry for using a "brand" name here, but I have been using it with old design engines for 30 years and have not had top end problems.

Bob, its not a choice here. You dont know what you get when buying 95 unleded. There is no such a thing here that free from ethanol guaranteed. Than we dont have marvel mistery here either. Liqui Moly or Metabond is two major additive supplier, I can have a look at them what they have.
So pick an other brand and suggest what to use .
I am all ears !

But it is a sheer joy ! I flew an hour today, made some vids , but will publish later.
Better than a two stroke for sure,even in direct drive. :)

Tom;
No that info was not gained by personal experience, LOL. There seems to be a standard where people compare this engine to the old VW. They are two completely different engines. The VW is generally 1600 cc's where as the 084 is 1378cc's The vw can be made to 2300cc's the 084 stays at 1378. But, in that 300 or so cc difference the 084 is 40 pounds lighter. The 084 is just a smaller engine capable of just so much. It will fly a minimax, it will not fly a 2 place plane.

Peter;
I did not realize your fuel problems over there. The engine is pretty much safe from the alcohol. There is an O ring on the main jet in the carb that can be swapped out to Viton. The needle and seat in the carb are stainless steel. The rest of the engine seals are in the oil so no problem there. The main thing is the fuel tank and fuel lines. There is fuel line you can order from Ac/Sp that is safe with alcohol fuel. If your fuel has no lead you should find something to add to it for top end lube. I would not look for a lead substitute. Just a thought here. Skyblazer and I use Bluemax oil in our Hirth engines. We are supposed to mix it at 100 to one. It does not smoke, you can't tell it is there. I bet if you used 2 or 3 oz of that oil or something like it per 5 gal gas you would be safe. I know I have drained old fuel from my max and put it in my fuel injected car with no problems at all. Something to think about any way Peter. Hey, when you going to post your videos?
Bob

I looked at petrol additives, there are so many that is hard to choose from. Some of the old timer guys suggest to use transmission oil (ATF).
I dont want to build up more carbon there, rather clean it and at the same time get more lubrication.
I am thinking of two stroke full synt oil also in more than well over 100 mix. Which is exactly what you suggest.

Hi Peter;
Yes, I think that would do what you want. Just enough to lube the top end and not cause carbon. I would give it a try.
Bob

Bob, Harless a question about oil.
Its for sure 20w40 or 20w50 because others are just too thin. But what about MOS2 Liqui Moly additives ? http://www.liqui-moly.com.au/products/oil-additives/ I have no filter on this engine.

I use 20W50 valvoline racing oil with a little STP oil treatment..

Hey Peter;
During the summer months I would use the 20-50 oil. Harless and I both use the same kind of oil. The racing only because the oil manufactures have snuck out most of the anti wear additives in regular oil. In your case Peter, use a good grade of 20-50 in the summer and use the STP if available or the Moly lub. One warning here. Make sure you break in the engine after overhaul with just the straight 20-40 or the 20-50. NO additives till the rings seat in. If your lube is too good, LOL, your rings will not "seat" in and it will burn oil and probably smoke some.
Bob

Quoted from Bob Hoskins

Hey Peter;
During the summer months I would use the 20-50 oil. Harless and I both use the same kind of oil. The racing only because the oil manufactures have snuck out most of the anti wear additives in regular oil. In your case Peter, use a good grade of 20-50 in the summer and use the STP if available or the Moly lub. One warning here. Make sure you break in the engine after overhaul with just the straight 20-40 or the 20-50. NO additives till the rings seat in. If your lube is too good, LOL, your rings will not "seat" in and it will burn oil and probably smoke some.
Bob

I think the additives you might be referring to is ZDDP. I think it's a lot of different things, but if memory serves the main one is Zinc. It's a key anti-scuff ingredient to prevent problems with flat tappet lifters on the camshaft lobes. I first heard about the issue on performance engines running flat tappet cams. I sell circle track racing parts. Cams could "go flat" in a 20-30 minute break in period. Racing oil will have more ZDDP than the current crop of "automotive" oils. The ZDDP was reduced/eliminated from oil because if created problems for catalyc converters.

Another oil that might be worth trying is oil intended for motorcycles with wet clutches. The clutches can't tolerate the additives in the newer ratings oils. The oil rating of the motorcycle oil I currently use is API rated SF/SG/SJ. Newer "automotive" oils are up to SN and maybe beyond. The "older" rated oil like the SF still has more of the ZDDP, I think.

Yet another possibility is oil intended for diesel engines, like Rotella from Shell. It has a different rating system than automotive oils so you woun't find the "S" rating like SF.

I'm not an oil expert by any stretch, but I've heard and read about it a fair amount. If nothing else it will give you some ideas to begin your own research.

Lynn

ZDDP, Zinc dialyldithiophosphate, is a compound that was introduced over 70 years ago and regularly added to motor oils. Its claim to fame is that it was the most cost effective metal on metal anti-wear additive…….and that is no legend. The compound was originally developed for use in airplane engines, but very quickly was found to be effective in car and truck engines for the anti-wear protection, in particular associated with flat tappets, overhead cam lobes, buckets and followers and the associated lifters where there is considerable pressure generated at the metal to metal interface and wear of the surface is known to be prevalent.

All tests that we’ve reviewed conclude that ZDDP is effective in moderating the wear, when formulated properly with base stock oils. ZDDP is also known to have anti-oxidant and corrosion resistant properties which are very useful in preventing aging of the internal combustion engine.

Over the last 40 years there has been considerable pressure to reduce the use of ZDDP in motor oil applications because of long term human toxicity concerns, and the fact that they are considered to be toxic to aquatic wildlife with long lasting effects. This can be alleviated with proper safety and disposal practices.

Further, influencing the decision is that catalytic converter life times are decreased by contamination with Zinc and Phosphates, and hence a drive to decrease the use of the additive to lower concentrations and in some cases its elimination.

As engine oil manufacturers decreased the concentration of ZDDP in motor oils over the last 20 years concerns became apparent about the impact on wear in engines, both classic and modern. It is now clear that modern passenger car engines are quite different in their need for ZDDP. Many are multivalve overhead cam engines with lower spring pressures. Those modern engines that still use an overhead valve arrangement use roller lifters instead of flat tappets and hence have lower pressure metal to metal contact and consequently require lower performance additives.

However the impact on classic engines was more concerning. There are reports from several years ago that problems were manifested in the rapid wear and almost total destruction of the camshaft and lifters in freshly overhauled engines. Some have blamed this problem on poor quality rebuilds, and also that the replacement lifters which were not meeting hardness specifications. But this problem is also attributed to the appearance of lubrication problems during the “run in” or “break in” period. The benefits of ZDDP are, after all, especially important during the break-in period for camshafts and lifters, and it makes sense that the excessive wear and destruction of parts will show up in recently overhauled engines well before we see it in higher mileage motors.

So these are some of our conclusions. These types of problems are never simple, but as a result of our reading we would offer the following observations:

    Consider using ZDDP as an additive in the motor oil during the run in period on a rebuilt classic engine. We are presently doing this on our rebuilt Jaguar 3.4Litre engine for the Mark 2.
    Be careful with the concentration of ZDDP used in your break in oil, as over dosing can cause increased wear – more is not always better! Always refer to the manufacturers specs and measure well.
    Consider using in your classic, motor oil which specifically contains ZDDP. Valvoline, for example, has a range of products as do. If you prefer, add ZDDP to your normal engine oil, making sure that you measure properly and achieve the manufacturers recommended concentration levels.

And remember, the ZDDP additive can help ensure a happy and long lived motoring.

Thanks for the info On ZDDP....I had never heard of the product.

What about additives like teflon coatings in oils...or fuels.

regards Arthur

when i rebuild engines...i spread a thin coat of STP or motor medic ( Motor Honey ) on all my bearing surfaces...journals....timing gears...etc. one of the hardest things for an engine is a dry start....i even coat the cylinder walls ands piston with it. i have got factory short blocks where they used a white lithium grease towards the same end. if the cylinders were honed or cross hatched they will wear in fine...if they werent they will take a lot longer to break in. the best thing you can do with any new engine or newly rebuilt one is to follow the factory proceedures for breaking it in. if there are none listed prime all oil lines with a drill if possible....give ample warm up....slower run ups..etc. check bolts ...retighten and/or retorque....check your settings ( valve lifter, etc. )...basically baby it for awhile and change the oil after a few hours of operation and at shorter invertals until broken in. i have seen few additives really accomplish any good. stp gas...marvel mystery oil...lucas top end lube and things of that nature are worthwhile. they will make you run smoother and with less friction. STP oil....be careful when using thick stuff like this....add when engine is warm and running if possible. i have torn engines down that had a pan full of honey....it doesnt necessarily mix well. de-carboning agents and fuel injector cleaners...can be used on occasion but make sure they are compatable with the compnents of your fuel system.....for the most part a GOOD ( spend a little more $$ for a better oil ) grade oil is all you really need...and change it often. i have used racing oil in my air cooled engines since the late 60s to good success. they have better additives and also anti-foaming agents.

http://www.aera.org/downloads/bip.pdf

Hi Charlie and Lynn;
You two did a great job explaining the problem. Everybody out there take heed about our oil.
Bob

I added some stabilizer and lead substitute to the petrol, and also added MOS2 Liqui Moly to the oil.  This oil is not a good racing oil, but a very basic, but I just changed it I though that I will replace the engine with the overhauled one, but its not going to happen that fast, since the engine is pretty good. I will fly an other 10- or so hours before replace it with a 20-50 racing oil also with some Liqui.

Its 90....100 F here, stormy, humid.  The 084 performs very well 2 hours before sunset. 1 hour of flying, yesterday, and I hardly can wait for the afternoon today to fly again.  Cyl head  300 F, oil 75 F no change.
What a difference to two strokes !
Consumption is a laughing matter.
I just simply dont know why the usage of  084 did not come into swing years ago.

I ordered a ground adjustable 150 cm long two blade reinforced composite prop for test. Cruising is really great with this engine, but I want to see what happens with take off distance if I go up to 3200 static RPM by adjusting those blades.

An other wonderful hour. I added some valve cleaner (just to make sure I burn those deposits).
I burned 1.85 US GAL / hour while cruising 70 mph on 2/3 throttle.
What else would you want ? :)

That works out to 37 miles per gal.

Quoted from TreeTopsTom

If those guys that are hording their 084's find Peters posts they are likely to increase the price of their engines. Sounds like you are really appreciating the switch to flying behind the 4 stroke Peter. Now your plane not only LOOKS like a real plane but SOUNDS like a real plane too....... LOL TTT

Currently there is one engine on the market I would trust to bolt on, not tear down and overhaul before. Thats Bob's spare with the re-drive. I was thinking about that to buy, but this one I fly currently will have hundreds of hours in it, I have a ring set for them. Maybe something to fiddle with for the winter months.... but its not sure.
The other is overhauled waiting to work with a prop-hub , and I got one incomplete with unknown condition just for spare. So if I add all these I have well over 2000 hours stocked for flying with them.

Hi Peter;
I really get a kick out of reading your posts. I can see you are really having fun with your Max's. I feel the same way about the little 084. a perfect engine for the minimax line. Between you and Harless, you two are the test engineers on this project. Please make sure you post the info so everybody can read it.
Bob

This is good as it is. I added 3 other hours since my last post.
I tried to feed the beauty with 100 octane fuel. She does not like it. She flies better with 95. Some I added some fuel stabilizer, and lead substitute, just to make sure.
The simple 20-40 oil got some MOS2 from Liqui Moly,not yet really noticeable  difference. This oil additive is grey, like graphite. The interesting thing that it does not darken the oil. After 5 hours the oil is clean almost as new. I watch it ready to replace this very basic oil with 20-50 racing and some more  additive, but it does not look tired at all.

https://www.youtube.com/watch?v=n_xo6wKT_Uc

Half throttle 100km/h cruise.
I just dont want to fly other than this. Day after day.  I LOVE IT.

I replaced the windshields and added some strut fairings. Simple. apx 4 inch of  0.5mm sheet aluminum bent and sticked onto the half inch wing struts by aluminum duct tape. Its very strong. No screws no holes just stick it on. Maybe a couple of km/h difference,  but I dont really feel that.

Looking good Peter. Fly the pants off that thing, LOL.
Bob

Quoted from Bob Hoskins

Looking good Peter. Fly the pants off that thing, LOL.
Bob

I agree with Bob! What a smooth sounding ride!.... Very nice!

There is one really serious problem with this aircraft.

The fuel tank is only 16 liters, and I dont see the last 5. So 1h 20 min is safe, than its like a russian rulett :) I need to do something with it. And an extra 8 liter would be nince so I could go for a 3 hour trip safely. :)

A new vid is here:
https://www.youtube.com/watch?v=dkniot8AJT0&list=UUFUev9XOLR_zH0QZyIwiSxA

Its a great little engine in a great little plane. No complaints.

Love your videos... makes me want a himax with A084! Wish I had engine rebuilding knowledge and skills of several of you on this board...

Quoted from RedBird

Love your videos... makes me want a himax with A084! Wish I had engine rebuilding knowledge and skills of several of you on this board...

Tony, parts are easy and cheap from Saturnsurplus. I dont have particularly large knowledge, beside that what I take apart , I can put it back the same way and measure tolerances, use torque wrench. Its a dead simple engine, made a shop rebuilt my one, and it was USD 400 labour, with some small machine work. I am sure Bob can help you even if you dont buy his overhauled, ready to bolt , redrived 084. Once you ve done this you will have a 1500 hours engine. Anyhow, looking at your new shop and woodwork, I am 100% sure you can do it if you want to.

The rules I discovered with this :
-closer you are to 170 cm and 75 kg is better.
-This engine is doing great as stock, no fiddle with it, no tuning, no changing carb.
-need a stainless steel exhaust with silencer (probably a 4 and a motorbike silencer)
-will not be a STOL for sure but 400 ft/min on 600 ft AMSL and you have a relaxed ride with much less noise.

I am really surprised that this engine did not get his place in UL aviation. It is a good engine for anything similar to Himax.

Hey Peter - Thank you for your thoughtful response. My issue is that I've just never been around engines much - more of a desk jockey my whole life; so I am a neophyte. I am slowly learning after a dozen or so years in aviation - but just very naiive, engine-wise. I'm ok with woodwork - no craftsman by any means; but I have a basic shop, can mix T88 and make a square cut ;-).

I'd love to buy Bob's engine, and his HiMax; but its just not in the cards for me right now - already a bit over-extended being between jobs and just acquiring Thunder's Eros (NO REGRETS!).

I've considered picking up a run-out A084 to use as an engine learning platform. But given that I don't think there is much in the way of public videos, and I don't have any mentor local; I'd be pestering the board every day for help! ;-).

I am find with 400 ft/min. I learned to fly in a 65hp Aeronca and flew it across southern U.S. in dead heat of summer with another adult aboard... Don't think we ever saw 400ft/min!! LOL

I might be too big for the A084... I am 100kg and 180cm...

Still, really tempting to pick one up and see what I could learn...

Tony,
I am an amateaur as you are. Dont take this as an advice, but in your case due to your weight
first I would think of one rib longer wing (which will not make you faster) or an foot long Hoerner wingtip I made on my first Himax. http://www.lonesomebuzzards.com/cgi-bin/forum/Blah.pl/Blah.pl?m-1324886458/s-42/highlight-hoerner/#num42
and definately a 1:1.6 redrive onto the 084 to swing a bigger prop.
But I think its very doable if you source a donor Himax with tired 447 or 503.

Quoted from pkoszegi

Tony,
I am an amateaur as you are. Dont take this as an advice, but in your case due to your weight
first I would think of one rib longer wing (which will not make you faster) or an foot long Hoerner wingtip I made on my first Himax. http://www.lonesomebuzzards.com/cgi-bin/forum/Blah.pl/Blah.pl?m-1324886458/s-42/highlight-hoerner/#num42
and definately a 1:1.6 redrive onto the 084 to swing a bigger prop.
But I think its very doable if you source a donor Himax with tired 447 or 503.

Ironically, I have thought about a longer wing project at some point if I use a lower power engine. (previously my Zenoah G25s drove the thinking).... I have time to ponder this, as for now I am focusing on my standard Eros build. I just love the sound and idea of the A064... thank you for your insights!

A couple of you guys were interested in the A084s that I had a line on.  Here's the latest.  I'm not ready to tell exactly where they are, but if you are within 300-400 miles of
north central Arkansas, it might be worth your time.  Outside of that, the freight might be cost prohibitive.  Sorry for the late return to the site.  I don't get on here much.  I'm
surprised that it has had so much traffic.  I don't get on here and give much information, and have learned not to give opinions or observations from my own experiences.  I've been
berated on several occasions for trying to be informative or give my opinion.  Won't happen again.

The engines are not new by any stretch of the imagination.  They have been inside but some have been sitting on the dirt.  I turned the cranks and think most of them are in pretty
good shape, but that is unfounded information and I don't guarantee anything at all.  I am going to purchase two of them and have made the deal already.  The guy that has them
will keep two also.  So that leaves 8 he wants to sell.  $400 will buy one, no problem.  The owner recently found out he has some form of leukemia, which is terrible!  I hope it is
treatable.  Super nice guy.  I'm going to talk to him this next week and pick up my engines, so maybe I'll have more information then.  Here's a pic as they sit.

If you are further away than 300-400 miles, you will have to do your own research on freight.  I don't think this guy feels like crating them up and shipping them.  One other
possibility.  I travel a lot to the Texas panhandle.  If you are close to that area, there is a good possibility that I could haul one that direction on one of my trips.

Looks like you found "The Motherload" of 4A084's! It's a shame I'm not in the market for one of them, since I'm only about 2.5 Hrs from North Central Arkansas. I have a 2A042 (the 2 Cylinder version) that I seriously considered using as I was building my MiniMAX, but finally decided to "keep it simple" and found a 277 Rotax. Actually, 4 total now. With what I've been through so far , re-sealing and re-ringing it, working out things for the belt drive, and now trying to sort out the tuning, I'm beginning to wish I had taken the 2A042 route. Oh well....water under the bridge, and I think I can see light at the end of the tunnel now. OK...that's enough cliches :)

What's the little 2-smoker with a belt PSRU at the right side of the picture?

I wish everyone success that goes the 4A084 route. There's a Yahoo group about them where you might find some helpful information too.

Lynn

Based on my experience with the 4a084, 2A042 is way too small to be OK for any max.

I talked and e-mailed with a gentleman, Kevin (I forget his last name...sorry) from West Virginia who has, or had, a MiniMAX with a 2A042. He seemed quite pleased with the plane's performance. He described the modifications he made to mount the engine, to account for the heavier weight, compared to a 277 Rotax, but I finally decided to just stick with the plans. I even had gone as far as buying one of the props he makes to work with the engine. He reported 55-60 MPH cruise at 3000-3100 RPM, and unless my memory is in error, flew it up to 9,500-10,000 Ft. ASL. I guess performance expectations are up to each individual, but I think I would have been happy with what he roprted after having talked with him.

As they say....your mileage may vary :)

Lynn

Hi All
I think this is what you are talking about. Don't underestimate what these little engines can do. here is a link.
http://www.youtube.com/watch?v=cj0hdymXfOg
Here is another
http://www.youtube.com/watch?v=L8uyf-I350c
Bob

Yes Bob, the top video you listed (Kevin's) is the plane/pilot I was referring to. Thanks.

Lynn

Hey Lynn;
Did you notice how smooth it was running? It was MADE as a 2 cylinder engine and balanced as such. Like the 084, out of the box, prop hub and go fly, LOL.
Bob

Today I received the 150 cm two blade composite ground adjustable prop. So an other good reason for test.
Just a reminder, the wood is 150 cm, about 8.5 degree prop, topping the rev at 2850, half power cruising with 100-105 km/h. Takeoff distance 150 m to rotate. climb rate little below 2 m/sec.

So I took the new prop , put it on and for the 2nd try it was matching the figures for the wood prop. So I thougt, ok lets shorten the takeoff distance. I went down to 7 degree pitch which resulted a 3050 static rpm on the ground. I went flying and as expected.
Takeoff distance to rotate shortened about 30 meters, climb rate is over 2m/sec (2.5m at 90 km/h) But cruising power went to 3/4 power with more noise.
To be honest: I did not like that. But its nice to have a prop which could be adjusted to the available runway.

Just for the record. There is one more problem with higher rpm : hotter engine. The oil was around 80C instead 70C before and cyl head climbed also up to 170 C vs before 150 C. So it may need to add an oil cooler if reducing pitch for better climb and shorter takeoff.

It's not a very good picture, but you can see the "loop" oil cooler on my 2A042. I patterned it after what others on the 2A042/4A084 Yahoo Group had done. Some on those groups who have experience with the military surplus engine maintain that an oil cooler is not an option. I don't know what others used, but mine is a coil of 3/8" O.D. aluminum tubing with 37 degree flare AN fittings. The pic is from last Summer when I test ran the '042, thinking I'd possibly use it for my MiniMAX, but ended up going the 277 Rotax route.

Please don't laugh too hard at my engine test stand, using my old, crusty trailer to hold it in place. It worked :)

Lynn

There are some news. :)
I simply love this engine. But I could not resist to make a 1.6:1 redrive.
Result :
Instead of swinging a 150 cm 7 degree two blader wooden prop direct, topping static rpm on 2850 , cruising 110 km/h on 2750 rpm with the redrive I took my 160 cm 3 blader carbon from my Hirth 2702 Himax (40 HP 2.54:1 redrive) and without any adjustment I got 3150 static engine rpm, cruising 2850 on 110km/h .
The two engine by HP is pretty much the same. If I would reduce 1-2 degree, probably it would go 3300 static rpm and it would perform just under a 503.
The takeoff distance is shortened to around 70-80 meters instead of 110-120 with a sluggish initial climb before.
With direct drive I would not take that to shorter runways than 450 meters, now I would do that on 300.
It is a wonderful combo and I dont know why not everybody is flying this way.
Its heavy but its an aircraft engine not a coffeemill.
I love it !!!!!!!!!!!!!!!!!!! :)

Something more to mention: I called arrowprop to buy their redrive but its not designed for tractor mode, and weight is about 2.5x of the one I designed. Arrow is good on boats, not on aircrafts.

Some new addition.
I have about 1.5 hours flying with the redrive. All above the airport which is 1200 ft long.

Lessons:
1, Vibration exist even on a smooth 4 stroker. The prop hub driveshaft screw loosen resulted a slight tilt between the two pulleys, which made the belt came off on a circuit. It happened in 2 minutes till it happened. It resulted a dead stick landing on the airport.
Loctite screw glue and a second nut fixed this problem.

2, Dont overtight the belt.
The edge of the belt is strongly pushed to the edge of the pulley, and started to eat the poliurethan reaching, the steel wires inside. The a steel wire end started to stick out about 2 inches. it was visible but not noticeable by sound, so I landed it on the airport engine idle.

Its still a better option with a redrive, larger prop, than direct from flying characteristic point of view. But here we go, adding one more part, which can fail and it will fail. Than you get into the question if it is a design flaw or just bad installation.

I dont get discouraged by this. Yes, the question came into my mind that direct could be simpler and problem free, but learning how much better this engine performs with redrive I still want to stick to the redrive. I can revert within 20 minutes to direct.

Others:
Higher rev does not necessarily mean that you need an oil cooler. The engine is open from the front now, and oil temp dropped very much. So the heat sink at the bottom of the oil sump works very well by itself if airflow is around it. My cowling was almost totally closed.

The startor solenoid failed, its a Skoda Favorit starter, cost USD 50 to replace with 30 min work.

Hi Peter

Good to see you're still enjoying your new engine.

I made my own reduction drives, mainly for the Robin EC44 50 hp 2 stroke, some years ago. Like you, I used the toothed belt system. The reason for this was because the data available showed me the toothed belt was better able to transmit the horsepower for a given width of belt, or number of vee belts. Also that being thinner in section thickness, and not relying on friction, the belt did not get so hot.

But, again like you, after a few hours - and a few inflight failures - I became aware of some of the problems with tooth belt drives.

Firstly, they are a less forgiving belt than vee, or multi vee belts. Because they are effectively a gear drive, there can be no slippage between the belt & the drive pulley. This means the belt does nothing to help even out the sharp drive pulses from the engine - it just transmits them. With vee drives there is the possibility of a small amount of slip that seems to soften the drive characteristics.

Secondly, they are super critical on getting the two shafts exactly parallel. With even the slightest misalignment, the belt migrates to one end, and chews itself up on the guard ring - as you have found!

So in the end I went for the multivee type belt such as these: http://www.fennerprecision.com/capabilities/belts/multi-v-belts.php. They still run a bit hot, but overall seem the better solution to me.

Good luck with your project.

Bruce

Bruce,
I also wanted the poly v but the I came across that there was no aluminium pulley off shelf only iron. And they were heavy like hell.
The other thing is that Raven http://www.raven-rotor.com/ and many other uses thoothed belts.
Today I fixed the tension problem and its not eating the belt so rapidly, but I could discover that the paralell alignment is really super critical as you say.

I run the engine for 75% power on the ground for 15 minutes and it was OK to take a 20 min flight above the airfield. I investigated again, and it seems I need 1-2 mm spacers under the 6 bracket mounting screws to get the two pulleys paralell. Thats my next step.

I am also in favour of poly V- belt, but I could not find suitable pulleys so far from aluminum.

My first aim was to see how this engine performs better with redrive if it really make sense, or stick to direct drive. I am convinced now that redrive is better, but now I need to enhance the drive system.
So far this experiment costed me USD 100 for the pulleys and belts, USD 120 for the work, USD 25 for the laser cut bracket and 20 bucks for the bearings. So for 270 bucks I can learn a lot about new things :)

The other thing which comes into consideration is dynamic vibration balancing. I have a Dynavibe balancer and I discovered that slipping belt will make new balacing each and every time the belt slips. And not thoothed belt will slip for sure.
So I am not so convinced yet which way I should go.

Peter

Well toothed belt drives can be made to work - as you say, the Raven guys apparently use them (I couldn't open your link). Just that they are not as easy or forgiving as poly vee.

One solution may be to get the pulleys machined? Shouldn't be too difficult to copy the profile off an iron pulley - or even from manufacturer's data - and machine an aluminium set. In my early days of experimentation I machined tooth belt profiles in a large nylon wheel that the prop mounted on (and it contained the bearings - it rotated around a fixed stationary shaft).

But it may cost you more than $100!

Bruce

Its winter time, I decided to swap the unknown history engine with the overhauled one which sits in my garage. I will repaint the whole aircraft and it will stay with the redrive. Today we have transported it into my friends workshop in a very easy way. Some pics.

The fuselage end of the wing sits on some foams, the spars fixed to each other. The other end is cushioned on the deflated tire, while the whole wing binded together cushioned to the fuselage.
It was 15 min to put this up. The transport took 30 min and its about 20 miles or so, so not for x country trip.

I am seruiosly thinking about some kind of a saddle which sits on the tail and holds up the end of the wings as well as the engine cowling and the other end. That way its even self supported and the aircraft is rolling on its own.

Old engine out today. The overhauled one is "dressing up"-

New steps- fuselage cleaned and sanded so as the wings.
Goose liver pathe sandwitches served.
A new way of carburettor heat box is created. Its an Y where there is a common axle with 90 degree different ventils from ram air and also from the exhaust. When one closes the other one opens.
I made a new throttle quadrant having the choke, throttle and the carb heat in one.

The wing sprayed today. I selected Mercedes Yellow 1625 the painter sprayed 1626 kinda butter color so both wings will be resprayed. We both happy.
Oh what a fun.

Quoted Text

I am also in favour of poly V- belt, but I could not find suitable pulleys so far from aluminum.

Peter, these guys http://www.aceaviation.co.uk/index_files/Page456.htm might be able to help.

Bruce

Thanks Bruce, they look nice, and it is a good option, but have to ship the things from India.

Its all painted and coming together back again....

Peter, What is all the stuff on the intake tubes for???

Quoted from Harless Greear

Peter, What is all the stuff on the intake tubes for???

According to my findings when I received the first engine from Bob and tested it around 5....7 degree C , it was building on massive ice. The carb intake was direct and all the engine was uncovered. It was very difficult to start, and also it could not reach higher rpms, it has rough running. When I covered the intake tubes with some kind of foams and duct tapes it improved a lot and also I took some warm air from the cyl heads.

As I bought this aircraft probably the previous owner had the same problem so he also installed foam and duct tapes (see the photos above) still had no carb heat box.

The best solution I find for an esthetic cover of the intake tubes is a foam tube called Aeroflex SSH solar heat pipe insulation. Its made from synthetic rubber, very flexible, is weather and UV proof. Its up to 175 C heat and - 40. This is flame retardant and self extinguishing.
Cost USD 10 per metre.

Peter

New engine cranked today with the new carburettor heat solution. It works fine. Its freezing today. I have a throttle quadrant which incorporates the throttle, carbheat and choke. /I will post some pictures next time/
The vertical and horizontal stabilizer is back and many more little details. New EGT and CHT sensors added, new oil pressure and heat sensors. Everything is doubled, since these sensors will work with my UL instrument developments. Should be back on the airport at the first week of Jauary, and needs at least 1...2 hours run in for the new engine before takeoff.
Next run is to put the windows back and add an additional small petrol tank to enlarge range which is currently about 2 hours 10 minutes.

pkoszegi,

It looks like the redrive positions the prop above the centerline of the plane. Do you think this will give problems?

My Challenger's prop is well above centerline, but it is a pusher, not a tractor design.

Quoted from The Termite

pkoszegi,

It looks like the redrive positions the prop above the centerline of the plane. Do you think this will give problems?
My Challenger's prop is well above centerline, but it is a pusher, not a tractor design.

I have not discovered any in-flight difference with this. The 582 Minimax is also out of center line , we tried downturned and upturned gearboxes, and could not tell the difference but the ground clearance is much better. There we sticked to upturned one.

Peter

Peter, Are you going to cut the piece that goes across the windshield???

Quoted from Harless Greear

Peter, Are you going to cut the piece that goes across the windshield???

I dont understand your question Harless. There is nothing what goes thru the windshield.

In your picture, there is a strip of wood that goes across the windshield from one leading edge to the other, you are supposed to cut that out at the edge of the plywood..

That's one of the few things I called Wayne about when I built my max..

Quoted from Harless Greear

In your picture, there is a strip of wood that goes across the windshield from one leading edge to the other, you are supposed to cut that out at the edge of the plywood..

That's one of the few things I called Wayne about when I built my max..

The windshield is bended over that and srew fixed from outside. I dont see any issue with it, this plane is like this for years.

Some more critical issues like how my wire haired dachsund will fit behind me.... :)

And as I promised a picture of the quadrant I made. Its not a lot of money involved in this project but a lot of time. I dont know if just buying one from Baxter would made my life simpler. Now throttle, carbheat and choke is at one place.

It looks like the dog has plenty room but he does need a safety harness so he can't interfere with the PIC..

PS: I removed the choke completely and plugged the holes so it could get a little more air, I now use a primer..

Does priming only with out choke fix freezing or even below freezing flight conditions ?

The Dog will have a harness. Otherwise he licks my ear all the way. :)

Done, and delivered back to the airport. I have to run in the engine first, than fly. The pushrods of the flaps and the nose cone is still in the paintshop. Probably wednesday. The white registration number is still missing, since I might change the Club, so as changes the number.

Very nice Peter! I'm excited for you! I look forward to a safe flight report.

- Sean

Peter, I don't think using the primer instead of a choke has any effect on carb icing but it does let a little bit more air get to the carb..

Multiply tries with wrong choke settings and flat battery can ruin your day. This happened yesterday.

Technically speaking, the Bing 54 doesn't have a true choke/throttle plate that restricts incoming air volume, it has an "enrichment system" which adds extra fuel.

The 084 has a true choke, not an "enricher" like most of the 2 cycles have..

When the choke is open it still has the flapper and rod across the intake of the carb..SO I removed mine completely so it could get more air into the carb. The air intake of the carb is approx. the same size as one of the tubes that go to the cylinders and there are four of them.. So I thought that anything to let in more air couldn't hurt..............

As of today:
Starter motor was not running with the flywheel- fixed, battery charge - fixed , ignition timing - fixed. Motor runs.
The alignment of the redrive belt is very sensitive, 1 mm washer at the top or the bottom makes the belt slip off either to forward or back. Either a tensioner/limiter will be installed but Iam really looking for alternatives to the cog belt to poly v belt, possibly redo the pulleys to PK shaped automotive belts.
I still can revert to direct drive within 10 minutes, but once you tasted it with redrive its better.

I'm almost positive the "choke" on the 4A084 operates on the same principal as my 2A042 carb, and most "old time" carburetors for that matter. The choke butterfly is at the opening of the carburetor. When the butterfly is closed, the air restriction increases the vaccum signal to the carb's jets and that sucks in more fuel than it would without the choke butterfly restricting the airflow and increasing the vaccum.

As I understand an enrichner circuit, like that on a Bing carb, it opens an additional fuel passage and additional fuel can be drawn in through that passage. That circuit is open to the "downstream" side of the carb's throttle slide. For the enrichener circuit to really operate though, the throttle must be closed, or very close to being closed, since it relies on a strong vaccum signal on the "downstream" side of the carb's slide. If the throttle is open very far there's not enough air restriction through the carb to create a strong vaccum signal at low starting and/or idle RPM to pull the extra fuel into the airstream.

In a way, they both operate somewhat the same. The choke restricts airflow, creating vaccum in the carb, which pulls additional fuel through the regular jets. The enrichner is an additional fuel circuit which allows extra fuel to be drawn in, but it's still using vaccum downstream of the throttle slide to do it.

I hope this helps :-/ I tried.

Lynn

Hey TTT;
Harless and Lynn got it right on. Tom, I mean this light heartedly, I think you should read a little more. :)
Bob

Done had one bag....... Wanna open another? ;D

Quoted from Harless Greear

...When the choke is open it still has the flapper and rod across the intake of the carb..SO I removed mine completely so it could get more air into the carb. The air intake of the carb is approx. the same size as one of the tubes that go to the cylinders and there are four of them.. So I thought that anything to let in more air couldn't hurt..............

Yes and no here... each cylinder is not pulling air all the time, only when the valve is open.  If you check the cam timing for the intake valve you will likely find on a 4 cylinder engine that there is no more than one cylinder pulling air at a time with gaps between.

But you are otherwise on the right track.  The engine is an air pump and power is dependent on how much air can get through the cylinder and more air is always more power.  On the exhaust side we have very high pressure to push that air through/out.  On the intake side we only have 14.7 PSI at sea level making the intake much more sensitive to improvement than the exhaust.

Some hot rod types have been known to airfoil the throttle butterfly plates and shafts for this reason.  Most aircraft intakes and carbs are awful air handlers (lots of sharp bends) and the improvement from airfoil or elimination of shafts is zero because of the other limits in the intake system.

Also like airplanes come in two types (fighters and targets) so do carbs: fixed venturi and variable venturi.  The Bings are variable venturi and "old" carbs are fixed venturi.  Fixed venturi carb --> second shaft/blade as choke and variable venturi carb --> extra enrichment fuel circuit.  Lots of fun stuff happens from there...

Sometimes I am completely amazed and impressed at some of the engineering and solutions people have come up with and carb design and operation is one of those almost magical devices.

The 084 stock carb works very well.
Carb heat does help a bit, and I will be testing ram air intake late spring as weather will allow.

Pkoszegi, if you are talking about having trouble getting the correct choke setting to start the engine you might try this the next time: flood the engine
turn the fuel off
throttle full open
crank the engine until it starts to run on the fuel in the cylinder(s)
turn the fuel back on as soon as the engine begins to fire.

If you have spark, when the mixture gets correct the engine will start.

I am not familiar with your engine at all! but this procedure has worked on carbureted engines from 2 hp. to 450 hp. and has proven to be the surest procedure to hot start fuel injected aircraft engines. That was using mixture control to turn off the fuel, so there was no concern about fuel in the lines or anything like that. Come to think of it, the smallest engines were on lawn mowers that sat through the winter.

No starter on one's engine (hand propping) tends to improve one's memory of procedures that work.

Using a primer instead of a choke will not help with carb icing. I have never flown an aircraft engine with a choke and all of the 4 strokers were subject to carb ice when the temperature was right. Somehow, 98% or more of my flying has been where the humidity was always high so the variable has been temp.

Hope this helps should you need it, but hope you never have to find out.

Bert,
Now its sorted out, so far I clocked 50 hours or so in this 084.
But when you put a freshly overhauled engine where all things are taken apart and put it back it requires a bit more than simple procedures of starting.
Once the battery is charged (or you are prepared for hand propping) and the starter motor and its flywheel alignment is good, and your ignition time is correct, so as your carb settings its a piece of cake to start the 084.
It starts very easy. Full choke, fully open throttle, no mags. 2-3 full turns, throttle back to idle, choke off, mags on and it cranks with no problem.

But a few tries with incorrect settings and you dont know if you flood the engine, plus the battery runs flat, and the starter moves off the flywheel it all comes to one annoying big pile of failure.
Plus adding a -5 C degree (23F) is really a trying moment of your patience .

Now its all done and it works like a swiss clock.

Now I am about to fiddle with the redrive pulley alignment. Temp today hits as low 14 F.
Peter

Run in with direct prop and instrument testing:
https://www.youtube.com/watch?v=mVF_417Wd7o&list=UUFUev9XOLR_zH0QZyIwiSxA

The engine overhauled, run, the redrive was redone with microbelt PK, alignment is set, the upper pulley runs in ATP oil, Bob was a great help to fix that.
I made a couple of takeoff and about an hour flight time already. Works Great.
The carbheat is a good option. It works very well in cold weather.

Here that goes with sound:
https://www.youtube.com/watch?v=l2n6AMx7CsA&feature=youtu.be

Very nice plane Peter! Congratulations.

Is the take off distance around 150 mts (500')?

Quoted from Ricardo

Very nice plane Peter! Congratulations.

Is the take off distance around 150 mts (500')?

Actually its about 70-80 meters. The same as other Himax. Climb is a bit sluggish, but at 500 meters (1500 ft) from brake release its at 100 meters (300 ft).

Way to go Peter! It looks like your having fun. :)

Quoted from pkoszegi

Climb is a bit sluggish, but at 500 meters (1500 ft) from brake release its at 100 meters (300 ft).

That's not too bad. The first 75'-100' is most important, to clear trees, powerlines, etc.

Some of you asked me about reinforcements. Apart of the firewall and the cabana struts I dont know any specials in the wings. But one thing I feel is very important if you install this relatively "heavy" engine. You must have a nice flex landing gear, either from alu spring or from composite, or any sort of dumper. That can absorb those very heavy loads and stress during takeoff and landings. If you guys are in the US, Georges composite gear looks like the one under the fuselage.
That needs some more thinking on "what if I install this engine in a Minimax".

Regarding the reduction drive, I had some learning curves, but now I have a good solution which is not very heavy. Redrive has a very positive effect on performance, and suprisingly no dramatic effect on cruising RPM.

I have a video of my take off that I use for comparing other planes take off performance , its 15 seconds long, The camera starts when the throttle is open. the take off occurs at 6 second and at 15 seconds is passing the camera that is at about 700 feet mark with a 100 feet altitude.
Your video starts the same way as the throttle opens yet it doesn't even leave the ground until after 15 seconds, that ground roll must be at least 700 feet long
See what I'm talking about here
https://www.youtube.com/watch?v=mivvHQ_wpWQ

Hi George
You neglected to tell us what your plane weighs.
Bob

Playing forensic science or NTSB:
Below is the map the airport. The elevation of starting point is 207m AMSL the other end of the airport 450 m and its 221m AMSL so uphill start.
The video was made at 3.30 pm. I marked the shadow of the windsack on the map. There was a slight crosswind on that day you may check it in weather history , but its basically 0 headwind at the time of recording. (but also see the shadow of the sock)
The static max RPM of the plane is curently set to 3250 engine rpm. Cruising is 110 km/h at somewhat 2800 rpm. So the prop is set to cruise performance. Its a fresh engine, fresh redrive so I dont do STOL takeoffs currently and I am light on throttle. I dont push this into the limits in the first hours.
The plane does not have wheel pants neither drooped wingtip. That means a lot reducing inducted drag at the time of takeoff.

Taking all that effect, measured more accurately the takeoff distance currently is 90 m. Which is 270 ft. Which is very very far from 700ft long as you guessed badly. However, next time George, compare weight, and get some more clear videos, since your ground roll can hardly seen, only when you have enough speed to put the stick on your stomach. Also it would be nice to see some headwind reference on your vid.

If I put my hoerner wingtips on this plane, plus let the static engine rpmfrom 3250 to 3500, I can really do whatever I want. Plus I can wait for some more headwind and show vertical liftoff but that would be a trick.

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