I just drove the Spit home for lunch (you can do that in the rural
town where I live). But when I tried to start it up after a 30-minute
sit, no dice. It won't catch up. This symptom first appeared in the
heat of the summer, and I thought it might have something to do with
vapor lock, even though there is a nice heat shield between the
exhaust manifold and the carb. But I decided to rebuild the carb, so
I dismantled everything and cleaned it thoroughly and then replaced all
the o-rings, gaskets, diaphragm, and even the deceleration bypass valve
seal. Well, things seemed a little bit better all around except that it
still refused to start sometimes after sitting for about 20-30 minutes.
When the weather got cold recently I had to fiddle with the setting
of the auto-choke. It wanted to run too fast at startup. The bimetal
spring has always been a problem, due to some bending by the DPO I
think. So I just replaced the spring housing with one off a carb I
bought cheap. Everything seemed fine recently. The car starts
immediately, even on cold mornings. It idles at about 1800 rpm at
first and then gradually drops to about 900. The only problem has been
that when I have to stop at a light right after normal operating temp
is reached, the engine sometimes dies. If I drive a bit longer, this
doesn't happen anymore. But now, I find that the inability to start
after a short sit is still there.
This feels like a choke problem. I am tempted to simply go with a manual
choke, but I would like to take one more whack at this. Do I simply
have to fiddle some more with the spring housing? I am very confident
that I have the fast idle screw adjusted correctly so that the gap between
the pin and the spring loaded cam in the choke housing is correct. Is it
possible that the deceleration bypass valve could somehow be involved. I
don't honestly know if I have it set just right. I have heard some
on the list say that it should just be sealed off with a gasket. I am
thinking of trying that next just to see if that helps.
I am pretty frustrated now. As I drove back to work in my beat up pickup,
I passed a guy in a MIATA driving around with the top down. It was a
little cool but plenty sunny, and I could have been doing the same. Damn.
I would appreciate any advice I can get.
Thanks,
Tim
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