Timing problems
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Freshman User
Joined: Dec 2003
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From: Havelock NC
Timing problems
Alright this is a wierd one. My 390 jumps timing on a cold morning startup. It only jumps on startup and in the morning when it is cold. Intial is set at 10 degrees btc and it always jumps to 8 degrees atc. Anybody ever had this problem.
Joe
Joe
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From: alaska
living here in alaska , I had that problem on a daily basis untill I bit the bullet and bought a new distributer and module . Mine were old so it made more sence to just replace both at the same time Good luck , bob
Post Fiend
Joined: Feb 2000
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From: Brea CA
I can only think of two things that would cause that.
1. The dist. is not being held down tight with the hold-down clamp.
2. The dist. drive gear pin has sheared and the gear is slipping on the dist. shaft.
This is assuming your vacuum advance isn't doing anything funny.
Barry
1. The dist. is not being held down tight with the hold-down clamp.
2. The dist. drive gear pin has sheared and the gear is slipping on the dist. shaft.
This is assuming your vacuum advance isn't doing anything funny.
Barry
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Freshman User
Joined: Dec 2003
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From: Havelock NC
I found the problem. i pulled the timing chain cover and the chain fell off. The cam gear is totally shot.Now I have the joy of dropping the pan and cleaning it and the pickup out since it had the alum that is covered with the nylon crap. Is there a chance I could have bent a valve?
Joe
Joe
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Joined: Jun 2003
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that depends on how far it jumped.............perhaps it didnt actually jump it was just slopping back and forth real bad.......i recently did mine and it made a huge difference.........those gears are a trip when there worn, they look like a throwing star the tips are so sharp..........when i did mine the chain could have been pulled of the gears but hadnt yet jumped........so i just replaced the timing chain and sprockets and i didnt have to alighn the cam sprocket and crank sprocket, i just.........how do i explain this.....i alighned the gears and chain, then slowly rotated the top one till it fit the cam and slid the crank one on..........in other words, the marks werent straight up because the cam and crank werent straight up.........they were in the same position as when id last shut the engine off....but you may want to start fresh and make sure the cam and crank are phased like like you would when building an engine, at tdc, so the marks are lined up when the chains on incase yours did jump.if that makes any sense......
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cjsdad1
1997 - 2006 Expedition & Navigator
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Feb 19, 2006 12:11 AM
