Matt, I believe the Evo .60 is meant to be run with no castor and 18% lube content. I will email separately notes I have collected on running the Evo .60.

John McFayden

          I'm thinking the 6 pitch prop isn't being well received by the engine. I was having good success with mine on lighter pitched props like 4 & 5's. The largest prop I used was a 13x4. I also was using the tongue muffler which had the holes drilled out slightly. Which venturi were you also using?

Guys,
Before we go any further in another quest to understand what and why is happening, let me tell you what happened today.
I have added the uniflow tube to the tank and tried to run the engine with the plane on the ground.

To my immense surprise, the engine run backwards (!!!) each time I started it and I tried six times.

It is impossible that the presence of the 3" of silicone tubing with second clunk in the tank caused it so it must be something else.

The question is what caused it and why.

Any ideas?

Comment: the engine I have has the Evolution part number EVOE0600. This engine is EVO60 NX R/C. The engine designed specifically for C/L (and no longer available in hobby stores) has the Evolution part number EVOE0605. I have removed the R/C carburetor and the rear mounted NVA from my EVOE0600 and installed the 0.200" ID short, blue C/L venturi with the C/L NVA.

Perhaps EVOE0600 and EVOE0605 have different exhaust timing and ports geometry therefore the C/L venturi and needle do not work well with EVOE0600?

On the other hand, there are many R/C engines that work fine in C/L after installing any C/L venturi with NVA.

Hmmm....

Thanks,
Matt

The Evo .60 CL Stunt engine is based on the .46 case, while the Evo .61 R/C is a bigger and heavier case. Absolutely, the timing is much different. More advanced crank timing and higher compression ratio can make an engine prone to start backwards, and the more advanced the crank timing, the more likely it will keep running. But it will never run at full song in reverse.

Remove your uniflow clunk and make a "fixed" uniflow pickup from copper tubing. Look at it this way...since you can adjust the "tank height" by adjusting the uniflow location inside the tank, how can it work repeatably if it's free to slam around inside the tank? Second option is to link the uniflow tube to the single clunk...but I wouldn't do it. There are some cute ways to do that, and some ugly ones. The bad part is that the two together are so much stiffer. 

There are some similarities with Dwayne's thread on the piped .46LA, now that I think about it.  Steve

My EVO 60 NX run finally well after changing the venturi, NVA and modifying the tank by creating the true uniflow setup (see the attached)
The pressure from the engine muffler feeds now the tank pressure line with the clunk and this clunk is very close to the clunk of the fuel feed line in any position of the tank.

I thought I had the uniflow setup before but it was not true uniflow. The tank pressure line was not fed from the muffler but was left open to the atmospheric pressure on the ground and to the air ram pressure in the air.

After the changes described above, I held the plane in my hands with the engine running, flipping it here and there for almost eight minutes and the engine run very stable and had a lot of power. I will work on 2-4-2 break now.

This engine (Evolution PN EVOE0600) has the exhaust timing around 150 degrees and it is small case Evo 60 NX R/C engine
Does anybody know what is the exact exhaust timing of the EVO NX C/L engine (Evolution PN EVOE0605)?


Also: I finally managed to completely disassemble my Jett60 and remove the shaft and both bearings that are indeed internally damaged.
         The friction in both bearings is randomly higher than it should be and this explains why this engine could not run with higher RPM and
         more power.
         Randomly higher means, that the bearings can turn smoothly for 2-3 revolutions and suddenly there is a resistance that feels like sand
         between balls.
         Next time it can be 1/2 or 5 revolutions and this "sand between balls" feeling appears again.
         I suspect the grooves of the races and/or balls are chipped or dented in the crash and some tiny steel particles pollute the bearings.

         I am ordering two new bearings from Dub Jett and hope the engine will run well again.

Lesson learned: never use the engine that hit the ground but looks good without disassembling it completely and checking EVERYTHING very carefully.

Thanks,
Matt