motor running up and down
Thread Starter
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Joined: Jan 2007
Posts: 80
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From: Sylvania Ohio
motor running up and down
You've helped before,,,I need help again. I got a 73, I've only had a month. Ran great! Today I drove it to work, and yesterday also. No problems. Coming home today it was running fine, then I noticed the RPMs going up and down, kind of like it was surging, first a little at a time driving and stopped,then it started to get worse going up and down around a 1500 RPM difference, at stop lights I had to take it out of gear to keep it running. Put in neutral, and it would go between wanting to stall and 2000 RPMs. It has a carter AFB carb. It ran fine for the last month. Any ideas
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Sounds like it could be a few things.
First, check to see what the condition of the coil and rotor are in the cap.
Next, do you have spark, and do you have fuel?
I'm thinking the distributor might need to be rebuilt, the fuel pump might be bad, and the fuel filter might be clogged.
First, check to see what the condition of the coil and rotor are in the cap.
Next, do you have spark, and do you have fuel?
I'm thinking the distributor might need to be rebuilt, the fuel pump might be bad, and the fuel filter might be clogged.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
My first guess would be carb problems....that's where the fuel gets metered for the engine. If it were a distributor problem, it would run really 'ratty' when it slowed down, as it would have a lot of spark misses.
Thread Starter
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Joined: Jan 2007
Posts: 80
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From: Sylvania Ohio
r unning up & down
I'm going out today to get plugs, wires, cap, condenser, rotor,fuel filter, ??? anything else you can think of? I just bought the car a month ago. It ran beautiful!!! Till yesterday, ANY more ideas PLEASE pass them on... Anyone in the Sylvania OH area that knows carb work, let me know I'll pay for help.....
CF Community Team
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From: Cape Cod, Mass.
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Sounds like it could be a vacuum leak. Check around the base of the carb. Also could be dirt in the needle valves of the carb or some type of a fuel filter obstruction. I would also check the float bowl levels. Carb may be flooding. Good luck 
Racer
Joined: Apr 2006
Posts: 340
Likes: 0
From: Warrensburg MO
I'm going out today to get plugs, wires, cap, condenser, rotor,fuel filter, ??? anything else you can think of? I just bought the car a month ago. It ran beautiful!!! Till yesterday, ANY more ideas PLEASE pass them on... Anyone in the Sylvania OH area that knows carb work, let me know I'll pay for help.....
Tommy
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