Can't Keep 2.5 cool

[mrfatride]

try leaning it out.. yeah it sounds funny but fuel gets stuck in the stock pipe and ignites and re-enters the motor via the exaust port. this causes temps to skyrocket

 

[CorvetteRob]

Mine got hot and idle fluctuated as well. I put a 150 cc fuel tank on it. No it didn’t fit, i switched the battery box over where the fuel tank was and drilled 2 holes to mount the 150cc to the frame where the battery box was, it hangs over a bit and the battery box is real close to the shock, but..... it worked !! The fuel is cooler and the temps don’t get high enough to cause problems. And I get 20-30 min run time, mostly 20 because I need to run at wide open throttle , yes.....I NEED TO! lol. Try insulating between the tank and the motor, it will work also, everyone says it’s tune, but I've been a mechanic for 42 years, it’s the heat warming the fuel too much. Been there fixed that ! Good Luck, See Ya !

 

[True Newb]

Mine got hot and idle fluctuated as well. I put a 150 cc fuel tank on it. No it didn’t fit, i switched the battery box over where the fuel tank was and drilled 2 holes to mount the 150cc to the frame where the battery box was, it hangs over a bit and the battery box is real close to the shock, but..... it worked !! The fuel is cooler and the temps don’t get high enough to cause problems. And I get 20-30 min run time, mostly 20 because I need to run at wide open throttle , yes.....I NEED TO! lol. Try insulating between the tank and the motor, it will work also, everyone says it’s tune, but I've been a mechanic for 42 years, it’s the heat warming the fuel too much. Been there fixed that ! Good Luck, See Ya !

Ahhhh ... as a mechanic of just as many years and builder of all kinds of race/performance and national concourse show cars, I was wondering about possible vapor lock on some nitro cars. My Losi Mega Baja has the aluminum fuel filter right up against the lower head (shown there in the owners manual too) and it gets HOT! The car will shut off occassionally and my thoughts immediately were vapor lock from the fuel being way to high in temp. Good call but being new to RC cars, I'm not sure how much "car knowledge" I can apply to these things. It's threads like this that will only help me in this new hobby.

 

[johnnydmd]

There inline coolers that you can use between the exhaust and tank that theoretically help with keeping the tank cooler.

 

[Greywolf74]

Ahhhh ... as a mechanic of just as many years and builder of all kinds of race/performance and national concourse show cars, I was wondering about possible vapor lock on some nitro cars. My Losi Mega Baja has the aluminum fuel filter right up against the lower head (shown there in the owners manual too) and it gets HOT! The car will shut off occassionally and my thoughts immediately were vapor lock from the fuel being way to high in temp. Good call but being new to RC cars, I'm not sure how much "car knowledge" I can apply to these things. It's threads like this that will only help me in this new hobby.

I have an LST2 and a XXL which are basically the same extact thing as the mega baja only with a different lid. Even though I wasn't having any issue with the fuel tubing running close to the engine I did eventually reroute the fuel line around the back of the tank instead of running it right behind and next to the engine. Seemed to make a slight difference. Just to be clear though I didnt reroute it because I was having issues. I just had to replace the old fuel line with fresh and decided to do that "just in case"