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Shade Tree Mechanic
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Shade Tree Mechanic
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I've been putting quite a few miles on the woodie lately and have developed a strong surging or bucking when I lift off the gas pedal--say when I'm going down hill or coming to a stop. I readjusted the idle speed down a tad, but this hasn't had any effect on the surging. Any ideas?
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Joined: Feb 2002
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The 52 when going down hill and with the pressure sligthly removed from the gas pedal will surge, I have found that it is time to reset the points and the timing. Seems to cure it. Nothing else I have done helps at all and that includes new fuel filters, new kit in the carb, and clean and gap plugs.
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Joined: May 2005
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Shade Tree Mechanic
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Shade Tree Mechanic
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glyn, my '51 chev pick up (30 years ago) did the same and the problem was easily solved when i replaced the vacuum advance canister. no help for woody though. jim
jf lewis
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Originally posted by dblclh:
glyn, my '51 chev pick up (30 years ago) did the same and the problem was easily solved when i replaced the vacuum advance canister. no help for woody though. jim Going to miss the Grand Junction affair but am tuning the car for a trip to the International show next weekend. Will check the vacum advance. Thanks.
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Joined: Sep 2002
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Shade Tree Mechanic
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I've reset the points, checked the plugs etc. I guess I'll have to recheck the timing...
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Joined: Jan 2002
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I would suspect that you have a vacuum leak....remember how we used to pull off the w/wiper hose so the glass packs would pop when you backed off.
That was also the cause of the 1951 with the bad vac. advance...the leaking advance diaphragm caused a vacuum leak.
Gene Schneider
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Joined: Sep 2002
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Shade Tree Mechanic
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It can't be a vacuum leak...the only vacuum I have is my windshield wiper off the exhaust. The carb has no vacuum advance...but now that I write this, is it possible that my distributor is rotating and affecting the timing? I never use the spark knob.
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Joined: Sep 2004
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Backyard Mechanic
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Backyard Mechanic
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I'd suggest advancing the timing with the spark advance the next time it surges to see if that cures it.
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Tech Advisor ChatMaster - 25,000
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"It can't be a vacuum leak...the only vacuum I have is my windshield wiper off the exhaust." Yes you can have a vacuum leak. You can have a vacuum leak between the carburetor flange and the exhaust manifold flange. You can also have a possible vacuum leak between the intake manifold and the cylinder head. 
The Mangy Old Mutt
"If It's Not Junk.....It's Not Treasure!"
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Joined: Nov 2001
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Tech Advisor ChatMaster - 25,000
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Tech Advisor ChatMaster - 25,000
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The Mangy Old Mutt
"If It's Not Junk.....It's Not Treasure!"
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True, I could have a vacuum leak between the intake and head(I meant I couldn't have a vacuum leak at the vacuum advance). I've checked for leaks at the carb. On the positive side, centralizing the brakes and lining up the front end certainly makes driving more relaxing and fun!
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Backyard Mechanic
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Backyard Mechanic
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Maybe the spark isn't advanced eneogh if he doesn't have to retard it any for starting?
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Well, I blocked off the vacuum pipe to the windshield wiper at the manifold. Surge has almost completely disappeared. A very slight lope/push when I first let off the gas. Over the last week (on vacation) I covered just under 900 miles. Low of 13 mpg. High of 18 mpg. Other than the surge, the only problem I had was when I drove through Boston. Lots of construction lead to a bit of a clutch problem. Also I learned to drive about 4 cars ahead to plan for stopping!But no over heating. Lots of smiles.
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