I need help diagnosing this problem. I'll try to make this short:
1. 49 Pan with Mallory Unilite Distributer, 12V system, Bendix Carb
2. Motor backfires through the carb when idling
3. Backfire repeats rhythmically - ba-ba-ba-pop, ba-ba-ba-pop, ba-ba-ba-pop etc.
4. Front plug is slightly rich, rear plud looks fouled
5. Replaced plugs and seemed OK for a short while then problem returned.
6. There is a small amount of oil on the outside of the rear head, near the base of the plug.
7. I can get the idle to smooth out by adjusting the idle mix screw and increasing idle rpm. But returns if I put the idle back down.
8. Just prior to back fire, a puff of black smoke exits the pipes, as if loading up.
9. Bike starts OK.
I do not have a lot of experience with these motors, but I'm willing to learn. I completely tore down and rebuilt this bike after buying from a "less than honest" ebayer. I did not rebuild the motor (it is an original, i.e. heads, cases, etc.). I do not want to throw in the towel now, because it's just getting interesting
So, any ideas?
Thanks,
Larry
Need Help with Idle!
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Please start new topics here: New Panhead and Flathead topics
Please start new topics here: New Panhead and Flathead topics
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