I've been off this list for awhile, but I'm back with a question
(what else?). My 1980 Spit 1500 with Stromberg carb and automatic
choke started giving me problems on hills several months ago.
Sometimes it would simply cut out and only catch up when I was
nearly at a standstill. It always started easily and ran well
except every once in awhile on hills, particularly after running
it, parking for a few minutes, and then running it again. I
replaced the fuel filter and the fuel pump seemed to be okay,
but the problem continued. I ordered a carb rebuild kit and
finished the job a few days ago. I struggled a bit to get
the carb tuned (questions about that below), but even when
the car idles beautifully and runs smoothly on level ground it
still chokes and cuts out on hills. In fact, it does it more
consistently now than before.
Questions:
1) The bi-metal spring used in the automatic choke must be way
out of calibration. Whenever I adjust it as per instructions
using the scribed mark on the housing, it never works well. I
have been doing it by trial and error. Recently I took the
heat mass, stuck it in the freezer, and painted a mark on the
housing to indicate where the spring pointed. Then I did the
same thing after immersing it in boiling water. So now I
know a little something about the extent of movement I get
over that range. So, is there any way to know how to line
things up?
2) Assuming that I know how to set the choke, what is the sequence
of steps for tuning the carb? Can I start it cold and adjust
the fast idle screw to get a reasonable rpm and then adjust
the throttle stop screw after it is warm? And where does the
mixture adjustment (adjustable needle on the air valve) come in?
I have been thinking that my problem on hills might be due to
an incorrect mixture. Is that possible?
Thanks for any help you can give.
Tim Gaines
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