I am a p-51 fan and had to buy the mustang but now the engine isn't running right! After first flight the engine sputters when going from low to high. After having one flight every one, including some guys wife, mess with the engine I packed it in the car and went home. The next day changed glow plugs and with new fuel I noticed air bubbles in the line so I changed all the lines thinking I had a pin hole but no luck. Please any one why do I have air bubbles?

It needs an OS #3 glow plug

The air bubbles are probably coming from inside the tank.

Your clunk line is loose or you got the lines reversed

the stock pluged burnt out on the first flight, checked the fuel tank does the air bubbles cause sputtering when going from low to high?

the Evolution engines have too many cooling fins and need a "HOT" plug to transition correctly.

Mixture adjustment effects the transition some also. If the low speed is too rich they will load up at idle and then sputter when you try to get them to run faster

So I might need to start with checking if its been moved from factory setting in the low speed, how do I find factory setting without calling support tech that never work? No telling what settings were changed! Didnt now about the hot plug Thanks!

On the Evolution engine it is hard to get the needles out of adjustment. They have travel limiters on them

I know that but some one removed the one from the low speed( new one on order ) to adjust it and I couldnt find it. That is what pushed me to take my ball and go home, and every time I call evo support tech they close at 5pm est and dont work weekends.

So you gathered up your marbles and went home?

On the low speed adjustment, open the throttle all the way and open or close the low speed screw to where it is clear of the high speed spray bar by about .020"