ORIGINAL: proptop
Now when you (opjose ) say that you can remove the baffle and still get ''gray goo in the same amounts'' do you mean enough to contaminate the fuel and to cause the engine to run badly or cause it to quit? Same question for a Pitts style or any other muffler?
I normally run my engines with filters so I've not seen the goo contaminate the fuel from the tank.
The particulates are pretty fine, and I've seen them get on the plugs and burn them out quickly.
When newbies arrive with these engines, I find that after the first few tankfuls we need to change the plugs to prevent problems.
So YES I've directly experienced the goo burning out a plug causing the engine to quit while testing the engine of a newbie's plane.
I've also had the same problem when using Pitts style mufflers on brand new engines.
On a new Evolution engine there is a good amount of goo, during the first few flights.
This can be mitigated to an extent by running a few tank fulls of fuel through the engine while on the ground, then flushing the crankcase with glow fuel... ( I've purposely flooded the engines, and let them drain out again with the plug removed... ).
The "goo" is heavier than the glow fuel so it tends to pool to the bottom of the crankcase, muffler, tank or where-ever it may get into.
ORIGINAL: proptop
I've run many hundreds of them.
But that does not equate to an equal amount of Evolution engines does it?
ORIGINAL: proptop
If the O.P. is getting enough gray stuff in his tank and it's not comming from the muffler, then there is something seriously wrong w/ his engine.
You would then have to say that ALL Evolution two strokers have "something seriously wrong" with them, as they all do this... and it's not coming from the muffler... You can test for this as I have... nor am I the only person experiencing this problem using different mufflers.
Poor design? Not enough clearance? I dunno.
I've run new Evolutions with Pitts mufflers, baffle less mufflers, mufflers swiped from other engines, etc. and the problem persists.
After about 2 gallons or more of fuel run through the engine, the goo all but disappears. By about the third gallon it is no longer an issue at all.
Given that the PTS is sold as "broken in and ready to run" I guess it would be safe to say that it is a big problem indeed.
No other two stroke engine I've run has ever produced the amount of particulates that the Evolutions do....
After you get beyond the goo problem, and the limiter problems the engines run well... ( Exception: The 1.00 NX's... )
Of course pulling the baffle doesn't hurt in the least either, and produces a bit more power from the engine.