Stumped!!!
Thread Starter
Instructor
Joined: Sep 2013
Posts: 118
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Stumped!!!
I have a 1971 C-3 w/350 motor. Got the thing running great in the last couple of weeks after changing the plugs & wires. Went to start it up this past weekend, it was warming up (cold-blooded) & all of a sudden it just back-fired @ idle & shut off like I shut the key off. Replaced the distributor cap & rotor. Have not been able to start it since. It will turn over & act like it will start, but then backfires & won't. Please help!!! Shows coming up soon.
Team Owner
Joined: Jul 1999
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From: Orange Park Florida
Le Mans Master
Joined: Dec 2006
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I have a 1971 C-3 w/350 motor. Got the thing running great in the last couple of weeks after changing the plugs & wires. Went to start it up this past weekend, it was warming up (cold-blooded) & all of a sudden it just back-fired @ idle & shut off like I shut the key off. Replaced the distributor cap & rotor. Have not been able to start it since. It will turn over & act like it will start, but then backfires & won't. Please help!!! Shows coming up soon.
Last edited by Big2Bird; Apr 25, 2017 at 09:10 PM.
Thread Starter
Instructor
Joined: Sep 2013
Posts: 118
Likes: 1
Stumped.
Will try that this evening. Hopefully it is that simple. I was not sure if a metal timing chain & gears would stretch that much on a recently re-built motor. But I have read there was a certain time when you could buy nylon gears??? Thanks for the quick responses.
Is my vette stock?? HAHA
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From: Im not allowed to tell you
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you could pull the cap and rotate the distributor forward or backward one postion to see if it did jump before pulling the front off. Also check for TDC on compression to distributor rotor position. I cut the center out of a distributor cap to check this and adjust valves.
I had a 72 F100 that did this when I pulled into a fastfood place years ago. It jumped when I shut it off and would just crank and crank
I had a 72 F100 that did this when I pulled into a fastfood place years ago. It jumped when I shut it off and would just crank and crank
Race Director
Joined: Oct 2008
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From: Long Island
I would check the coil and points if you haven't already. I just had the rub block on the points break off on a 67. Same symptoms..
Bring the engine to TDC -top dead center and check the rotor position it will tell you if the chain jumped. Mark the distributor body for the #1 plug , this will make it easier.
Bring the engine to TDC -top dead center and check the rotor position it will tell you if the chain jumped. Mark the distributor body for the #1 plug , this will make it easier.
Last edited by BLUE1972; Apr 26, 2017 at 11:14 PM. Reason: spell
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Instructor
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From: Athens AL
The purists will object to this recommendation, but I can't help but suggest it. Last week, I pulled my OEM distributor (with Pertronix kit) and Accel coil and installed a $57 EBay HEI distributor. I did a quick timing adjustment based on my vacuum gauge and took it for a test run. What an incredible difference! The car pulls much harder now, and the throttle response is much improved, especially right off idle. Best $60 I ever spent on the car, by far.