i have an evo 46 on of the early ones that came on a pulse pnp. the engine never ran reliably would flame out in mid flight all the time i recently took it all apart and cleaned it all up and found that the front crank bearing was leaking worse than i thought as i could see daylight around the inner race lol. replaced the front bearing re-assembled and now that it is put together i built a test stand so i could get it working proper before it goes into a new plane. with the engine on a test stand it actually starts not too bad at least better than ever before. it runs great at idle but when i rev it up it will stall out every time. i tried richening it up 1 turn and tried leaning it out one turn, both of these adjustments are from a base setment of 2.5 turn out from totally closed on the main needle adjustment. nothing done with the idle needle. any thoughts or tips or advise ? what should i check? what should i try? thank you.

Chris

It needs a hot plug like an Enya #3

i havent tried that. i have tried an os 8 and a fox regular but i ill pick up a hot plug and try it. thanks for the advise anyone with other advise?

The OS A3 is a hot plug

The engines are cold natured and I guess they have too many cooling fins

i trie that and not much difference, found that if i leave the glow ignitor on it will rev a little higher but still no full throttle. also this thing get so hot in only 30 seconds of running that you cant even touch it any other suggestions

Didn't some of the early Evolution engines get shipped without an "o" ring at the base of the carb, causing air leaks and lean runs. Wouldn't his cause over heating and lack of top RPMs?

Chris,

There's been a lot of discussion about the CL-only EVO 36s on some CL sites. Much comment that that engine, at least, prefers fuel with low or no castor oil in the fuel 'package.' Of course, a total oil percentage around 20% is indicated.

That engine reportedly likes to carry a bit more load than many "modern-metal" engines. (We often run CL Stunt engines at higher RPM on flatter pitch props, if the engine does better that way... The EVO 36 is said to want a bit more pitch and diameter. )

...Raises the question - what fuel are you using? Old fuel runs funny. Fuel for ABC/etc engines used in older iron engines may cause damage. Iron engine fuel in an ABC-etc. engine may have too much castor, and may gum up the the precise fit cut into it.

The other points to date - plugs and gaskets - may help a lot. The CL .36 may not be designed as nearly like you 46 as would have experience with it be useful for you... Just a few other areas to consider, if that's the situation.

Luck

For some reason this engine is running "lean"

hmm i wonder where the air leak is then i guess i will have to start looking at o-rings

Some thoughts come to mind.

These engines had limiters on the needle adjustments. Have these been removed yet?

If the low speed needle is in too far, You can screw the high speed needle all the way out and the engine will still be too lean on the top end.

thanks for the tip it is very possible that i have the low speed needle in too far i started with the 2.5 turn outs and havent even thought about it since. that does make sense and maybe i will back it out another half turn or so. any advice on how for out to make it? and was my 2.5 turns out on the highspeed needle correct?

that is good starting place for the high speed needle

Chris,


None of the people present here can tell you the proper setting for your high-speed needle...

Any setting given to you is ONLY a place to start; as Jim elaborately wrote.


"Anything running badly on the ground, will not become better in flight!"

Because this always holds true, the fact that you mentioned not having touched the low-speed needle, its incorrect setting is probably at the base of your problem.
Even an engine designed for operation by beginners, requires some effort to be made to get it adjusted.

The low-speed needle controls much more than just the idle mixture... It is actually the engine's primary fuel control; which determines the 'fuel curve' at all settings, from idle to ~80% open throttle...
The high-speed needle must, of-course, be open enough; so as not to deprive the engine of its fuel needs at all part-throttle settings...

It is only at ~75% throttle or more, where engine RPM changes very little; that the setting of the high-speed needle becomes the only control and has a direct effect on engine operation.
...But you can 'twirl' that needle as much as you want at part throttle and as long as it is open enough to support the low-speed needle's position; it will have no effect at all...


The low-speed needle must be set to provide optimal response and transition, at all part throttle settings...
In fact, the engine may sound a bit rich... but when it sounds perfect in steady-state, it may conk-out, or 'stumble', when you try to open the throttle further...

It is your responsibility to make it a bit richer, so response to throttle input will be perfect (no stumble; no burbling/spitting, on throttle-up).


And let me add this; in any reciprocating engine (glow/spark/Diesel...), there is no 'eternal flame'...
It does not and cannot 'flame-out'...
This is just 'turbine wannabe' jive, used by 'boys who want to be be men - but are still mere boys to be'...

Your glow engine can shut-down, stop, conk-out... not flame-out!

understood thanks for the advise ( and the lecture about flame outs ) lol all taken to heart i will try to adjust the idle needle and go from there will keep you all posted

The Evo .61 had a period where some were shipped without the carb o rings. I seem to recall that a few 1.00s went out that way, but I could be wrong about those.

i got fed up with the engine so i decided to put it in the plane anyway to see if that would make any difference i then reset the spray bar needle with the carb at what should be close to idle and it seemed somewhat better then i pulled the plug out and looked at it to see if the entire coil glow and found there to be what looks like rust spots on the plug so i guess this points toward contaminated fuel, the weird thing is that my os 46FX runs great on this stuff still and i have only now seen the slightest bit of the tell tail bubbles on the top of the bottle, i guess it is quite possible that the fuel tolerances of these two engine are different so we will try that, think i am on the right trac?