Strange stalling problem.

[Ryan with savage]

At my club meeting yesterday (1/8 Buggy) and the guy I race with, was having a problem that neither of us could fix or figure out.

We'd start the car and he'd do a few laps to warm up etc and them come in to get topped up with fuel 1 min or so before the start. (Rolling Starts). Car was running fine.

I'd fill it up (only takes maybe 5-10 seconds max) and out down the pit-lane...he'd go....not bogging down, not too hot, perfect. Then 20-30 metres later it would just stall. So I run, pick car up, restart it (which it would instantly) and off he'd go.....and carry on without any further problems.

Everytime he needing refueling the engine would die somewhere down the track. (Which is more of a problem in the finals obviously) We tried leaving it on the box for 30 seconds after fueling and it would be fine, put it down and 30 metres later.......kaput....

Didn't blow plugs, changed plug, rechanged and then went back to the original, made no difference, didn't flame out at any time other than after fuelling, didn't run hot, idle was consistant, started easy, drive train is fine... cannot figure out why it does it. Any ideas anyone?

 

[rs4evo]

could be fuel splashing up into the pressure return line causing the motor to go lean..i read something on that a while ago...let me see if i can dig it up
http://www.rchobbies.org/engine-tuning.htm
if you scroll down on that page it talkes about the full tank lean bog

 

[Ryan with savage]

thanks rs4

Anyone else??

 

[sly2136]

while refueling you guys letting it idle or blipping the throttle. i'm wondering if your letting it idle and its loading up on the low speed then when you need to go its loaded up with fuel and causes it to flame out. i don't want to slam anyone here but a flame out is not a lean bog. its caused from excessive fuel in motor putting out the glow plug. i would try leaning the low speed a little bit sounds like your very close so just go a little bit. another way you can tell if its a lean bog is right before it stalls the motor should rev real high before dieing. if it just flames out thats different.