Carb Problem?...Advice?
Thread Starter
Instructor
Joined: Mar 2001
Posts: 197
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From: Shoreham NY
Carb Problem?...Advice?
Last year I replaced my non-original carb with a re-built Rochester Q jet off a 72 auto, mine is manual. The motor runs great; no problems while driving. However, every once in a while, after I shut it down it will backfire. Any suggestions as to what the problem might be? If it is an adjustment problem, can someone point me in the direction of proper adjustment procedures. Lars? Thanks.
Ben
Ben
Thread Starter
Instructor
Joined: Mar 2001
Posts: 197
Likes: 0
From: Shoreham NY
Re: Carb Problem?...Advice? (comp)
Comp,
That confirms exactly what a friend of mine told me but I wanted to get further advice from the experts here before I fooled around with the adjustments. Thanks,
Ben
That confirms exactly what a friend of mine told me but I wanted to get further advice from the experts here before I fooled around with the adjustments. Thanks,
Ben
Tech Contributor
Joined: Aug 1999
Posts: 14,370
Likes: 6,364
From: At my Bar drinking and wrenching in Lafayette Colorado
Re: Carb Problem?...Advice? (7vette2)
Is it actually backfiring, or is it afterfiring..? Backfire is a pop up through the carb. Afterfiring is a pop out the exhaust. If it's really backfiring (up throught the carb), you have a valve timing/sealing problem related to camshaft or valvetrain components. This is not carb related.
If the car is afterfiring (out the exhaust) after shutdown, you most likely have a combination problem of rich idle mixture and high idle speed. Make sure your idle speed is correct, and if that doesn't solve the poblem, lean out your idle mixture a tad.
If the car is afterfiring (out the exhaust) after shutdown, you most likely have a combination problem of rich idle mixture and high idle speed. Make sure your idle speed is correct, and if that doesn't solve the poblem, lean out your idle mixture a tad.
