Subaru EA81 Engines

[DGL Fox]

Hi All,

 

To someone that has no idea about the EA81 engine could I ask anyone that knows, I have been reading a little about them and I was thinking how reliable are these engines compared to say the Rotax engines, I see in photos that it only has one spark plug per cylinder, do they have a dry sump arrangement and or twin mags?

 

So how I ask, how reliable are they really, would people here have one fitted to their aircraft if not why not? I will be interested to hear peoples opinion on it.

 

David

 

 

[facthunter]

Certainly popular in the past The redrive is often flat belt. They turn out a bit heavy for RAAus. Motors don't have to be dry sump. The Subaru installation in an RV doesn't leave much room for a nosewheel support truss. Don't know about the dual spark. Nev

 

 

[Bubbleboy]

If you do a search on here for a member called Bushcaddy from memory. He has a beautiful EA81 installation I have seen at Natfly. He reports fantastic reliability with what he has done. As mentioned they can be a bit heavy. I have flown a Pietenpol with an EA81 and it flys beautifully. I have an EA81 sitting in my garage here I bought for a plane build one day. I nearly ditched the Corvair I am putting in my Pietenpol but decided to stick with it.

 

Scotty

 

 

[bushcaddy105]

Yes, a bit heavier than a Rotax at 92Kg including starter, belt reduction, engine mounts, 50 amp alternator and 4 litres of oil in the sump. Payoff - about 25% of the initial cost of a 912S, cheap service costs, much simpler engine bay plumbing. Possible negative - one only electronic ignition system with platinum plugs, but when did you last have a failure of your car's electronic ignition system? It comes down to personal preferences and standards - I'm happy with mine after 8 years (and 608 hours as of yesterday) behind my EA81.

 

 

[facthunter]

Failure of electronic ignition system in a car? Plenty ! About 8 to a standstill from quick memory in the last 17 years . Nothing to do with maintenance. Magneto failures in about 7,000 engine hours None in an aviation environment. Nev

 

 

[planedriver]

And don't overfill the engine oil and blow the seals. My son had his Subaru taken away for scrap about a month ago for that very reason.

 

Prior to that, it was running like a charm.

 

 

[DGL Fox]

Thanks all for the comments,

 

So apart from the weight and only one of everything, they are cheaper on the maintenance side and cheaper to buy initially, so I guess they would be a nice engine to have in a aircraft, I see the Foxcon's use them in their standard fitment of an engine., so they mustn't be to bad..

 

David

 

 

[facthunter]

You are not going to be starting with a new engine though, so if it has had a hard life in a vehicle perhaps it shouldn't go in an aeroplane. Nothing is useable forever, so try to get a good one to start with. You will still have to go over it of course. Nev

 

 

[bushcaddy105]

You will of course rebuild the engine, as a modified camshaft is fitted. It is most unlikely that oversize pistons will be needed, as the cast-in cylinder linings just don't wear. My engine had 220,000 km in a car, but still had hone marks intact. Measure the crank pins and regrind as necessary. The bottom end of EA81 engines is very strong - there was a factory built version with fuel injection and turbo which is rated at 125 HP and uses the same crank. It isn't possible (or advisable) to just bolt up a used engine out of a car - it won't develop the power needed in the rev range desired. If you are not into engines and understand what mods need to be done, please don't try!

 

 

[facthunter]

You would want to do lot of crack testing too, but you can't assess fatigue. Nev

 

 

[jeffd]

Yes, a bit heavier than a Rotax at 92Kg including starter, belt reduction, engine mounts, 50 amp alternator and 4 litres of oil in the sump. Payoff - about 25% of the initial cost of a 912S, cheap service costs, much simpler engine bay plumbing. Possible negative - one only electronic ignition system with platinum plugs, but when did you last have a failure of your car's electronic ignition system? It comes down to personal preferences and standards - I'm happy with mine after 8 years (and 608 hours as of yesterday) behind my EA81.

hey john ,i have been reading about the subaru motors as i actually have had a subaru car b4 and worked on others .my question is ,is it just a matter of buying a subaru motor and then doing the mods yourself where you can or is it more involved than that.as i have read there seems to be different vehicles for ignitions etc to source bits of pieces from which would reduce the overall costs i would imagine.i read with interest the motors were actually designed for a/c from the start .let me know as i havent decided on anything my friend david(magishme) and i am very keen on looking at the r80 and initialy we were considering the ul motor as another friend of ours is putting 1 in his bushcaddy r80.thanks for the info so far .jeff

 

 

[bexrbetter]

.i read with interest the motors were actually designed for a/c from the start .

Subaru cars are an arm of Fuji Heavy industries who also build planes and the divisions have nothing to do with each other.

 

Subaru's first horizontally opposed engine was a 1000cc aimed at the competitive 1000cc car class in Japan at the time (mid '60's) - with a whopping 50hp and nothing to do with planes other than Fuji had good insight into the layouts of Continentals and Lycomings which they used in their planes - and none of them less than 250hp. That experience, and VW of course, may have swayed them to go with the flat 4 design.

 

It is a car engine and always was a car engine - a bloody reliable one at that though having rebuilt a couple of them and importing them for 15 years. In fact in my entire mechanical and workshop career, I can't remember a 1400, 1600 or 1800 ever coming in with major failure of any kind other than extreme mileage simply needing rings and bearings. Get a shock the first time you see how narrow the big ends on them are too, nothing else comes close.

 

I own an EA81 with redrive in an airplane so yell if you need some pictures of the setup.

 

 

[Old Koreelah]

Interesting, Bex. If you track back through their history you find Fuji arose from the ashes of Japan's first aircraft builder: Nakajima.

 

 

[Old Koreelah]

Hi All,To someone that has no idea about the EA81 engine could I ask anyone that knows, I have been reading a little about them and I was thinking how reliable are these engines compared to say the Rotax engines, I see in photos that it only has one spark plug per cylinder, do they have a dry sump arrangement and or twin mags?

So how I ask, how reliable are they really, would people here have one fitted to their aircraft if not why not? I will be interested to hear peoples opinion on it.

 

David

David there is a Subie for sale in the latest Sport Pilot.

 

 

[Bob Llewellyn]

hey john ,i have been reading about the subaru motors as i actually have had a subaru car b4 and worked on others .my question is ,is it just a matter of buying a subaru motor and then doing the mods yourself where you can or is it more involved than that.as i have read there seems to be different vehicles for ignitions etc to source bits of pieces from which would reduce the overall costs i would imagine.i read with interest the motors were actually designed for a/c from the start .let me know as i havent decided on anything my friend david(magishme) and i am very keen on looking at the r80 and initialy we were considering the ul motor as another friend of ours is putting 1 in his bushcaddy r80.thanks for the info so far .jeff

I have an EA-81 in the shed - I prefer the EA 81 to the R80 (I assume we're talking BMW R80?), because the torque pulses are half the size if at the same power / revs... and the EA-81 is water-cooled, which makes it easier to get low cooling drag. I expect the EA-81 to be very reliable if I get the installation right, and the best value for money for a two-seater.

 

 

[DGL Fox]

Sounds like they are a very good engine if set up right..

 

 

[zenith 701]

Subaru cars are an arm of Fuji Heavy industries who also build planes and the divisions have nothing to do with each other.Subaru's first horizontally opposed engine was a 1000cc aimed at the competitive 1000cc car class in Japan at the time (mid '60's) - with a whopping 50hp and nothing to do with planes other than Fuji had good insight into the layouts of Continentals and Lycomings which they used in their planes - and none of them less than 250hp. That experience, and VW of course, may have swayed them to go with the flat 4 design.

 

It is a car engine and always was a car engine - a bloody reliable one at that though having rebuilt a couple of them and importing them for 15 years. In fact in my entire mechanical and workshop career, I can't remember a 1400, 1600 or 1800 ever coming in with major failure of any kind other than extreme mileage simply needing rings and bearings. Get a shock the first time you see how narrow the big ends on them are too, nothing else comes close.

 

I own an EA81 with redrive in an airplane so yell if you need some pictures of the setup.

Hi I saw that you made a reply to some one...I sure am in need of a distributor system or other type of ignition system. .thank you

 

 

[daza]

Hi I saw that you made a reply to some one...I sure am in need of a distributor system or other type of ignition system. .thank you

If you're looking for parts or info re Subaru's in the States, check out the Ultimate Subaru Message Board

 

Daza,

 

just another Subaru nut!

 

 

[will kirkbride]

Hi All,

 

I have an EA81 in my Zenith 750. I have completed the first flight and am now doing the 25 hour test flight stage before gaining full registration. My engine is the fuel injected,turbo version without the turbo.

 

It has an SDS computer to control the fuel injectors and ignition timing. The system uses a crankshaft trigger to control the spark and has a coil pack with 4 separate coil leads and hence has no distributor as such.

 

The engine has the custom Wade camshaft and has custom forged pistons and steel con rods which is probably overkill but thats OK with me,better to be overengineered than not.

 

The system uses a waste spark,but as Bushcaddy pointed out,this would probably cause a problem with a carby set up, however the injectors sit in the intake just above the intake valve and my engine revs to 5500 cleanly

 

with no problems.

 

I would not recomend installing this engine if you dont have a good grasp of the mechanics of it all as it takes a lot of engineering to get it to work properly. However, it is a sweet running engine when sorted. Mine weighed 92kg

 

also with the redrive, engine mount and oil.

 

Cheers Will

 

 

[hankthetrader]

Where do you obtain a Wade cam for an EA-81?

 

Thanks,

 

Hank

 

 

[will kirkbride]

Where do you obtain a Wade cam for an EA-81?Thanks,

Hank

Hi Hank.

Wade cams are no longer in business but their main man left and formed Clive Cams

 

If you contact Clive on 03 97585977 and ask for the 240 Wade grind for EA81 he will be able to help you.

 

I see you are from Alabama so you would need the Australian prefix before the phone number if you are going to call.

 

I deal with Clive and find him helpful.

 

Message me if you want to know more.

 

Cheers Will

 

 

[gwaf]

Talk to Helmut at Foxcon - Home

 

 

[gwaf]

Foxcon - Subaru EA81