My money is on a vacuum leak. While the car id running, spray carb cleaner at
the bottom of the carb. where the intake manifold meets the head, or anyplace
where the intake can either be taken apart or opened up. Including both ends
of any vacuum lines. Do this one spot at a time. If the idle should smooth out
or increase you have a leak in that location.
>===== Original Message From Michael Graziano <mgrazian@ltcm.com> =====
>Oh yeah. At idle, (1k rpm) the engine is stumbling a little. Not stalling,
>just running a little rough. And when you goose it quick, there's a slight
>hesitation and a cough (though the carb, that's when I scared myself). The
>plugs are clean (no oil, and no black sooty stuff, in fact, they were a
>little white the last few times I pulled them). ANd my compression is OK.
>All within 5 except one within 10 psi (approx. 125 to 135).
>
>Could a valve be burnt? And maybe I'm still testing for intake manifold
>leaks incorrectly. What is a tried and true procedure that some of you
>folks have tried?
>
>Michael
>
>
><mgrazian wrote>
>
>Hey folks.
>
>I checked and readjusted the valves this weekend. A few questions arose. I
>think the valve gaps were in OK shape. They were supposed to be set at
>0.010 inches. I found some that were as far open as 0.013. Does that make
>a significant difference? Is it OK to reuse the gasket as it was in good
>shape, and I used some permatex black gasket glue to help with the seal. I
>have a new one that I bought for the job, but misplaced it.
>
>Also, the intake was still backfiring. I rechecked for leaks on the intake
>manifold. Nothing found (doesn't mean nothing there). I enrichened the
>mixture a little. Now the exhaust smells a little like gas, and it still
>backfires throught the carb. Nearly scared the S#$% out of me when I had my
>hand outside the carb barrel and it backfired.
>
>I've got the timing at 10BTDC, from Bentley's and Haynes. Should I advance
>it more or less as the next test (or should I test something else first).
>And if I advance it, is that more towards 12BTDC or 8BTDC.
>
>I'm determined to solve this damm thing. Even if I have to take a shotgun
>to the engine. At least it won't backfire anymore. ;-)
>
>Mike
>
>BTW: I changed the accelerator cable with one from a bicycle brake. I
>can't believe what a difference it makes. ANd for only $3.
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