Rob -
when you say it idles great when it's cold are you saying the high idle is
working correctly and the engine is revving at a higher rpm and you can
slowly tap the throttle and the engine will slowly lower in rpm's as the
choke opens up? If so then the choke circuit is working properly and I'll
leave that part of the carburetor along.
Could you do me a favor and find the PVC Valve and remove it and make sure
the valve still contains the rattle ball inside. I've know them to fall out
and then you have a big vacuum leak so if you check it and it's their that's
one less thing to worry about.
After the engine is warmed up and you say it want to die, that tells me that
it's probably running lean since it runs fine in the morning when the choke
is on. If you were to just turn in the idle screw to raise the idle up
wouldn't that cure the problem of the engine wanting to die?
Raise the idle up to keep it running on it's own when the engine is fully
warmed up and then connect a vacuum gauge to manifold vacuum. With the
engine running adjust the mixture screw to obtain the highest vacuum and
then if the idle is to high, just back out the idle screw to lower the
engines rpm. You may want to go back and recheck the mixture screw one more
time to be sure it's set correctly for the highest rpm.
The other way you can tell if your engine is running lean would be to cup
your hand over the throat of the carburetor to restrict air flow into the
engine. If the idle picks up then your running lean but if it starts to
stumble then it's on the rich side
I normally check for leaks around the carburetor base and mid portion of the
carburetor by spraying around those areas with some WD-40. I realize that
people say that it now longer contains a flammable liquid to cause the
engine to raise in rpm but it still works because it has the ability to
block the leaking area and thus raise the engine rpm because it eliminating
an air source which was causing a lean condition.
Let me know what you found out.
Joe
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