Mike, except for the fact that they aren't drilled for a muffler, they are good engines.  The original strap-on mufflers are hard to find.  They are more often run in a wet 2 stroke than a classic 4-2-4 for stunt or sport flying, and they are hard to wear out.  I've attached .pdf copies of the instruction leaflet and parts list.  The venturis came in 3 sizes, the smallest being used for stunt or sport flying.  Pat King has posted drawings of the venturis, and MECOA has some Enya parts including (I think) both high and low compression heads.  Bobby Brooks (shtterman?) on eBay also has some parts.  The engine was not supplied with head shims (good design!) but the compression can be reduced if you add a shim.  The detachable front end makes disassembly and reassembly very easy.  And they do run best on Enya #3 glow plugs, which are slightly shorter than a "long" glow plug.  The Enya 35-IIIB is the same as the 35-III except it has a round venturi.

Enya calls for 20% Castor for lube. I would not run less than 20% oil, not more than 25% of that(5% of total fuel) synthetic. For sport or stunt run the low compression head.

Pat

Greetings Gents,
I came across this thread that doubled my knowledge of the Enya .35.
I have not been able to get an Enya .35 running - it is a plain vanilla 5224 with a wide/large small (0.265 narrowest) venturi.
Orifice is pointed straight back.
Running fox fuel - 10% nitro, 29% castor.
New wedge tank.
I got one sputtering, short flight in today on the Ringmaster, so at least I flew(!)

I picked up on the fact in this thread that I have the large small venturi insert, so that may be a root of my problems.
Running an OS 8 plug, MA 10x6 prop.
Maybe the extra castor is a problem? coupled with the large venturi isn't a good setup.
Any help appreciated.

More edit - after the engine refused to give a good run last week, I disassembled the engine, cleaned up thoroughly (although it was pretty clean to begin with) and reassembled with new gaskets. That did not change the running behavior of the engine.

Thanks, that's an interesting point and totally possible. Since I got this setup used, I assumed the engine had alread been broken in.
I'm attaching a screen shot of just the break-in info from the instructions posted in the thread, above, and I'll bring smaller props next time I get to the field.
I have to go to the field to play with this engine because it so dang loud(!) My muffled Fox's I can get away with from time to time at my house.
Even though the engine had apparently been run before, it might have only been run a small bit.
The plane, itself, had much barn rash - covering had puncture wounds - but it didn't look to have been flow, before.

I meant to say the orifice was pointed straight down in the venturi, I can see where "back" might mean pointed back at the cylinder.
Looking forward to trying these couple of things out - except we are forecast to have 3 1/2 inches of rain, today.

I had trouble making one of these run until I switched to 22% oil.  Too much castor causes problems.  You got a good deal - I had to pay $15 for mine.

Thanks, all - all good info. I'm set up to be able to drill/tap the holes for the muffler - I have a tongue muffler coming in, to tap for pressure, and try that setup.
I'll let you know what happens. I should be able to get new runs in with changes this Tuesday.

I have used the5224 35's before. They run good . You can drill out the dimples on the exhaust port and the an fp 25 muffler will fit. I cut the tailpipe of the muffler and bored the hole to 3/8.   George

Since you had the engine apart, which side of the piston was the baffle on? It should be away from the exhaust outlet. Also the exhaust port on the cylinder liner should be lower than the intake port. I wonder about your needle valve, too. Does it close the fuel flow completely off when you screw it closed (gently please)? Someone might have swapped in one from an R/C carb and I believe they are shorter.

-Chris

Actually the exhaust port on the sleeve will be higher than the intake port, not lower

Randy

I've run a few of these with good results.

One thing.  They're not as strong as they look.  I blew up some using them hard in the old Slow Combat event.  Crankshaft & conrod.  That was in the plain bearing days, before they threw away The Rule Book.

Greetings Gents,
I came across this thread that doubled my knowledge of the Enya .35.
I have not been able to get an Enya .35 running - it is a plain vanilla 5224 with a wide/large small (0.265 narrowest) venturi.
Orifice is pointed straight back.
Running fox fuel - 10% nitro, 29% castor.
New wedge tank.
I got one sputtering, short flight in today on the Ringmaster, so at least I flew(!)

I picked up on the fact in this thread that I have the large small venturi insert, so that may be a root of my problems.
Running an OS 8 plug, MA 10x6 prop.
Maybe the extra castor is a problem? coupled with the large venturi isn't a good setup.
Any help appreciated.

More edit - after the engine refused to give a good run last week, I disassembled the engine, cleaned up thoroughly (although it was pretty clean to begin with) and reassembled with new gaskets. That did not change the running behavior of the engine.

Before I double checked your post text, just looking at the picture, I thought the glowplug might be a Fox product, of which I have very low regard. But if you're certain that it's an OS #8, ok. A longer glowplug is not generally a problem, as long as there is no contact with the piston crown or baffle. A short glowplug in an engine designed to use a long reach glowplug will usually run very poorly.

I noticed that the NV appears well thrashed. With a similar appearing OS NV, this can lead to significant problems needling...NV looks good, but isn't. Pointy end or spraybar is bent, I think. One click can change from much too rich to much too lean. Perhaps this is a similar problem? This is why I much prefer Randy Smith's NV Assy's. They're either (very) good or (very) obviously broken. Other than that, I don't have any significant Enya experience.  Steve