My 1980 MGB with a ZS carb doesn't want to idle at a sensible speed and I'm
hoping someone can give me some pointers.
When it's cold everything seems to work o.k (at first). It starts o.k and
idles at somewhere around 1200 RPM (which seems o.k.). If I then drive it for
a few miles everything seems to behave normally until I stop and let it idle.
The engine is then idling at around 2000 RPM. Despite this it runs smoothly so
I thought the automatic choke probably isn't sticking open. I thought that if
the choke was stuck open the mixture would be way too rich and it wouldn't
idle smoothly. I know that the throttle isn't sticking open because I can see
from looking (and feeling the carb) that it has returned to the start position.
This fast idling seems to continue for as long as I drive the car. However if
I stop, leave the car, then come back and start it again after five or ten
minutes it idles at around 800-900 RPM with a warm engine. If I drive it
again and stop, the idling speed will be higher (around 1100 RPM).
I hope this makes sense because its confusing me and I don't want to blindly
start taking things apart in the hope of bumping into the problem. Any clues?
Another thing, when I registered the car there was no problem with the
VIN number and I have records from new so I know it's the right number. However
my insurance company tells me that their computer says the VIN number is for
an MG Midget. I'm no expert but I can tell the difference between a "B" and
a "midget". Anyone heard of something like this before? I'm a bit concerned
in case the car is stolen since the insurance company might try to pay me
for a midget (which is probably less $$$).
Finally, recently people have been writing about getting the heater in TR's to
work. Well under the dash on my MG there's a lever which seems to open and
close some kind of air vent. What's this for? Whether it's open or closed,
and I don't know which position is which, I still seem to get cold air blowing
in. Neither position seems to change the way the heater works.
Thanks in advance for any suggestions.
Paul.
paul_hemson@mentorg.com
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