AIR IN THE TANK

[nitro burner]

Hey guys i just got one of V2 50 raptors back together with new engine and have a problem. the problem is i have large air bubbles in the fuel tank i know it getting air from some place, I do what cound chaged the fuel lines and in the tanks as well checked the muffle for licks and so on and there is the :arggg: air bubble in the tank what did i over look?? thanks for any help.
P.S. I know the engine getting air its trying to over heat.

[Sar]

You are getting air in the header tank? Have you checked the head bolts on the engine to make sure they are tight? A loose head bolt will cause the engine to run lean.

[LuckyLandings]

Like Sar mentioned. Unless it in your header tank it shouldnt matter much.
I just wanted to add you might want to make sure your glow plug is sealed tight with a good warsher seal. You could get air that way. I loosen mine some times for cold start to loose some compression and I notice more air in my tank. (could be my imagination though..lol)..
Good luck.. JG

[VTHELINUT]

Your tank may be bubbling because of a vibration. I just had the same problem with one of my helis . I dident check the fanhub balance and I had bubbles around the back corners. I checked for leaks and replaced all fuel lines and still bubbles. I striped the motor and balenced the fanhub and all bubbes went away. Check the balence on everything.
Check Fanhub, Topstart shaft, and tail shaft first.
Thay can be the #1 bubble causer !
Good luck
Mike