Air leak on TT 39?

[Rex-flyer]

Posting this for a buddy of mine that I fly with. We were out flying our raptor 30's today on lunch and after I flew my tank he fired his up, he flew for maybe 5 minutes tops and then the engine started to die out on him, he landed and we checked the temp and he peeked at 300 F. His raptor was doing this before so he replaced the tank, lines, cleaned out the carb and put a new filter on it. He is flying the same as me at the factory setting on the high speed @ 2 1/8 out and my temp peeked around 180ish and we are both running 15% cool power with the thunder tiger .39. Any suggestions on what may be causing this? Bad o-ring on the carb causing an air leak, junk in the carb? To note the 5 minutes he flew before it bogged it flew fine.

[vandelescrow]

I don't have the engine you are using but once I lost the screw that keeps the carb from falling off and yes, it caused the engine to go lean. Took a while fidling with the needle valves till I noticed it was missing. Special size meant custom order and wait till you can fly again.

You said the engine went to 300, I'd check the cylinder for scaring. I've blew an OS50 hyper at 250, needed a new sleeve, ring and piston.

[forjer]

I overheated my .39 a couple weeks ago. Couldn't get it rich / cool enough and a tank of gas would only last about 8 minutes of light flight. I pulled the carb...changed all the fuel lines...checked the rubber...and I think it ended up being a loose muffler section. I'd still like to get some new o-rings and gasket for it.

[Rex-flyer]

He had it some what apart after we got back from flying and the cylinder looks good along with the piston so I dont think he smoked it, hes replacig the o-rings on the carb and cleaning it out to see if it was blocked at all. We will find out today if it works, thanks for the replies

[WayneBrown]

We've had a few of those at the field.. check ALL the screws in particular the head screws and make sure they are tight.

[Rex-flyer]

Getting ready to go fly now, will post later if he fixed it

[forjer]

Well?

[Rex-flyer]

We flew Friday on lunch and his raptor flew for 2 tanks, first tank, temp stayed just over 200, second tank it was 220ish and towards the end of the tank it started to bog out on him again, so I dont know what it could be now. He did have a crash a few months back so maybe he has a hair line crack in it or something. What temp are you guys with .39's running and whats the max temp you guys run at? Im usually no higher then 190 F but I could use a couple of clicks lean for little more power

[Raptorman37]

i dont have that motor but the general consensus around here seems to be about 180-190F on a 30 size motor and a just a tad warmer for the 50s

[Rex-flyer]

Yeah thats what I have been hearing too about the temps.