Well, my Midget runs but still has the same problem that led me to ask for
advice a couple of weeks ago (the last time I got to work on it).
Some background: 1979 MG Midget - single Z-S carb. One of the springs in the
clutch pressure plate _fell out_ last November (seems like a real long time ago)
Anyway, the simple "remove and replace clutch" led to bigger and better things,
including - regrind camshaft, replace timing gears, replace oil pump, install
oil cooler, etc, etc. SOOOOOOO, It has been back together for several weeks
now (I only get to see it on weekends, at best) and it still doesn't run very
well.
The PROBLEM: It's sucking _way_ too much gas. I can't get the colortune to
even start to hint at anything but yellow. Obviously the mixture is screwed
up but I can't seem to fix it.
I've had the carb and choke apart numerous times and everything seems to be
OK there (although I freely admit I'm far from an expert on these things).
The timing seems OK, the fuel pressure is regulated (we had some "trouble"
with a leaking main jet!).
The question: ANY IDEAS????
My big concern is that something is screwed up internally - cam timing wrong for
some reason (not likely but having seemingly exhausted other options, I'm
heading for the big, nasty ones) or something like that. I don't think the cam
is the problem because it does run - it just runs too rich. Seems that if the
cam was screwed up there would be major problems.
Other ideas:
1) Ignition - I think this is OK (I haven't messed it up yet) but
maybe if the spark isn't strong enough, the gas wouldn't burn completely??
This seems like a real long shot.
2) Maybe the needle is worn out. The car ran OK before but maybe the reground
cam changed the demand on the carb to the point where a worn needle would become
more obvious.
3) Something else in the carb is screwed up that I haven't thought of yet.
4) ?????
Any Ideas????
thanks,
Rich Hill
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