Dear Spridgeteers,
I've recently noticed that my '65 Sprite was running rich (black, carboned
spark plugs, black smoke on acceleration). Not having a ColorTune, I used a
trick that is posted at the VTR site, which is to lift a carb piston by
1/16 inch and listen for a change in rpm. If the rpm goes up and stays up,
that carb is too rich. If instead the engine stumbles, that carb is tool
lean. If the rpms rise then fall back to about what they had been, that
carb is about right.
Anyway, both carbs appeared rich, as I'd thought, so I turned up the
mixture screws a few flats, doing the lift check each time. Everything
seemed great yesterday afternoon on the test drive. However, this morning,
I found that at idle, the rpms slowly drop until the engine dies. Or, if I
slowed in gear, bringing the rpms down, then it died much quicker. However,
if I revved the engine, sometimes the idle would stay high enough to keep
running. I of course found this out in rush hour traffic creeping uphill.
Any thoughts on what's going on? I did not reset the idle screws when
messing with the mixture. However, yesterday the idle was much higher once
the mixture was leaned (went from 750 to 1000). Could it be the temperature
difference between today (~40 F) versus during the test drive yesterday
afternoon (75+)?
Thanks,
Jeff
Jeff Boatright '65 Sprite MkIII __o_\__
http://userwww.service.emory.edu/~jboatri/
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