Model Forum / Radio Controlled / Land Models / June 2006

It's starving for fuel or getting too much air.  It starts in a lean
situation, resulting in high RPM and then dies due to lack of fuel or too
much air in the mixture.  You either have an exhaust pressure leak (header,
coupler and/or pressure line), a blockage or leak somewhere in the fuel
tank/lines/carb or maybe a head gasket leak and/or backplate leak..

If I were you, I would:

1.  Remove carb and blow it out using compressed air and denatured alcohol
as a solvent.  If it sat for awhile it might have gummed up.
2.  Replace all fuel and exhaust line.
3.  Deep six the gas tank in a bowl of water and check for leaks by plugging
the feed line and blowing into the pressure line.
4.  Check all head gasket screws for tightness.
5.  Check header screws and header gasket for damage.
6.  Check exhaust coupler (between manifold and pipe) for leaks.
7.  Check engine backplate for leaks.

HTH,

Doc

sounds like the low speed needle is in too far (lean)...
this can burn up the motor bearings pretty easy...