Timing question
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Timing question
While checking the advance timing on my 390, I noticed that the mark would jump around quite a bit, is this normal or should I be investagating more? I am running a Mallory YL dual point, and all engine parts are new. I can only think of two things which might be causing this, 1 the plug is not firing every time, 2 the mech. advance is not holding steady, COMMENTS???
Steven
Steven
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From: Brea CA
Timing question
Worn timing chain or your rotor isn't phased well with the cap.
Put a big socket on the crank and turn it back and forth while watching the rotor. See how far you can go back and forth without the rotor moving.
Barry
Put a big socket on the crank and turn it back and forth while watching the rotor. See how far you can go back and forth without the rotor moving.
Barry
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Timing question
Timing chain is new, I have heard of rotor fazing before but have never knew how to check it, I've also heard you can drill a small hole in the dist. cap and hook up the timing light to that plug wire and watch it with the strobe. Question is how to you adjust an out of faze rotor?
Steven
Steven
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From: Brea CA
Timing question
I used to run a YL dizzy on my CJ many moons ago. Can't remember if it had it but you adjust the position of the breaker plate on points or for electronics you shift the position of the pickup.
What's happening is the rotor is not pointing directly in front of the tower when it fires. Instead it is offset and the spark has to jump a fair distance to hit the tower which varies the timing. To see it you have to waste a cap and drill a hole by any tower. Hook up a timing light to that plug wire and watch the position of the rotor when the light fires.
Barry
What's happening is the rotor is not pointing directly in front of the tower when it fires. Instead it is offset and the spark has to jump a fair distance to hit the tower which varies the timing. To see it you have to waste a cap and drill a hole by any tower. Hook up a timing light to that plug wire and watch the position of the rotor when the light fires.
Barry
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From: Long Island USA
Timing question
Originally posted by Steven Taylor
While checking the advance timing on my 390, I noticed that the mark would jump around quite a bit, is this normal or should I be investagating more? I am running a Mallory YL dual point, and all engine parts are new. I can only think of two things which might be causing this, 1 the plug is not firing every time, 2 the mech. advance is not holding steady, COMMENTS???
Steven
While checking the advance timing on my 390, I noticed that the mark would jump around quite a bit, is this normal or should I be investagating more? I am running a Mallory YL dual point, and all engine parts are new. I can only think of two things which might be causing this, 1 the plug is not firing every time, 2 the mech. advance is not holding steady, COMMENTS???
Steven
On edit: Check it even if the dizzy IS new... you never know.
Worn upper bushings are the biggest reason to go electronic...
ak
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Timing question
Well I've checked the top bushing as suggested, its OK. checked the rotor phasing, it appears to be real close to dead on, so now I guess I'll have to figure out whats next. Guess I try a different dist. just to be sure its not the dist.
Steven
Steven
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From: Long Island USA
Timing question
Originally posted by Steven Taylor
Well I've checked the top bushing as suggested, its OK. checked the rotor phasing, it appears to be real close to dead on, so now I guess I'll have to figure out whats next. Guess I try a different dist. just to be sure its not the dist.
Steven
Well I've checked the top bushing as suggested, its OK. checked the rotor phasing, it appears to be real close to dead on, so now I guess I'll have to figure out whats next. Guess I try a different dist. just to be sure its not the dist.
Steven
Another thought. Are you sure the timing light is working fine? Does it run OK?
ak
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Timing question
Coil is Mallory Promaster for points. dwell per set of points is 26, mech. advance set at 26, Accell 8mm wires, Autolite 45 plugs. Timing is set at 10. Truck runs real good, but would probably be alot better when I get this worked out. I checked the timing light on two other cars I have and its OK as well. Is it possible the mech advance is sticking?
Steven
Steven
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Timing question
Well here's the latest; I think I have found the problem, the end shaft has .062 in play, Mallory say .008-.010 is called for..... Looks as if I need some shims!! You can feel the advance plate hit the bottom of the points plate when spun real fast by hand. Thanks for all the help.
Steven
Steven
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Timing question
Well that was it, got it apart and shimed, truck runs like a Swiss watch on steriods!!!! When that B&M C-6 hits second gear ya better be hanging on!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!
Steven
Steven
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