Model Forum / Radio Controlled / Land Models / October 2005

If after 2-5 minutes it's only reading 172*F, you're likely running too
rich, which can cause a stall.  The fact that it easily restarts kinda
suggests this as well.  My Sportwerks .26 (same as Mach .26) runs rich and
smokey at 260* and has gobs of power, so it sounds like you need to lean her
out some to get the temps up to where it will stay running and where it
won't bog down at idle and stall.  These motors require heat to run and stay
running, and 172* isn't enough!

I would crank up your idle speed via the idle set screw a bit and see if
that keeps it from stalling.  If it does, this confirms that you're too rich
all around.  Start with HSN and lean till you get temps between 220-280*
with lots of smoke and good top speed, then lean in the LSN until it idles
reliably and doesn't load up until 30 seconds or so.  Then, set the idle
where you want it.

HTH,

Doc

If this has started all of a sudden then I would consider looking at all
your fuel lines again and make sure you havent got any air leaks from split
hoses or even a tiny pin hole.  Make sure theres no air bubbles in the fuel
line while your running.  Check your fuel tank as well for proper sealing
around the filler cap and cracks or damage and also have a look at the
primer.

Try disconnecting the hose from your carb and prime the fuel line until the
fuel comes through then prime some more with your finger over the end of the
hose to make sure its pressurising and theres no bubbles getting into the
line.  Also try disconnecting the pressure line from your exhaust and blow
through it to check for air leakage.  If need be just replace your fuel
lines anyway.

Its very strange if it was running good one day and bad the next for it to
be a tunning thing if the weather conditions were similar.  Also are you
topping up the tank after it stalls?  Try running it again after it stalls
without topping up the tank.

Other things to check for are loose head and back plate bolts.

Cheers
Richard

too rich
or
too lean
or
binding/seizing (bearings/drivetrain)
or
too much flex (something hitting flywheel or spur or clutch/driveline)
or
air leaks
or
bad new glow plug
or
bad new motor