Robert Jones scribed:
Subject: Help! My B still doesn't work!
> I am at a complete loss now. I've tried everything, and my MGB is still
> not running right.
> first couple runs, it began to miss and backfire under hard acceleration.
> It ran fine on the drive home, though.
> runs the same as before, missing and backfiring through the carb under
> acceleration and backfiring through the tailpipe LOUDLY when deccelerating
> with engine braking.
Standard mixture rule: (Murphy aside)
Backfiring on acceleration is usually due to running lean. (carb spits)
Backfiring on decelleration is usually due to running rich. (boom in
exhaust becomes more apparent with low restriction mufflers.)
Perhaps the carb is tuned rich to overcome a vacuum/air leak, and so
displays both symptoms? Is there an air pump fitted? An MGB with no
gulp/PCV valve or solid throttle plates will usually backfire some
under engine braking, due to high vacuum causing rich running.
> I turned the
> distributor until it ran smoothly. With it advanced ALL THE WAY, it idles
> GREAT
"ALL THE WAY"? what's that? You can turn the distributer all the way around,
if you want to. Are you using a timing light?
Also, don't forget the "I've already done that syndrome". Just because you
think you checked/fixed something doesn't mean it's working. IADTS can
cost a lot of time and money for those who beleive they couldn't have
missed/messes something the first time. It may be time to go back and
check everything by the book, from square one.
Roger
-"Nah, I just installed a *new* condensor when I put the engine together."
" What do you mean the wire's shorted?- Garnett
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