Topic: Rough idle after new water pump?
in Forum: C3 Engines
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I just replaced the water pump on my 77. For some weird unknown reason, it is idling rough now. I never touched the carb, wires, etc. and do not understand this. Is there something about changing the water pump that would create this problem that I don't know about? Thanks for any suggestions and input!
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Duncanville, TX - USA
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Is this a vibration? If it is, then it may be the fan is not centered on the pump shaft, or the pump shaft may be bent...
If you loosen the belts, does it idle smoother?
If you loosen the belts, does it idle smoother?
Joel Adams
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Lifetime MemberSHELBYVILLE, TN - USA
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might check to see if you accidently knocked off/broke a vaccuum line....
StingrayJim 
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my guess would also be a vaccume line . On mine in the past, I've just bumped vac. lines doing repairs w/o even knowing it ,that later caused problems.
Scott:
I recently experienced the same thing and the car did overheat. What does that have to do with the rough idle???
Jim
If the engine got hot enough it could have breached a head gasket. The introduction of water in the combustion chamber can at a minimum foul a spark plug or worse, warp a valve. This of couse is only one of several possiblities.
Scott
Lifetime MemberApache Junction, AZ - USA
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Does your 77 have a Coolant Temperature Sensor? On my 82 it is just above the water pump and if it is unplugged or malfunctioning, similar problem arise.
No, my car did not overheat before changing the water pump. It does not have a coolant temperature sensor on it. I am not experiencing a vibration from the fan but rather a small "miss" when idling. With acceleration when parked it smooths right out fine. I'll have to double check the vacuum hoses but I am sure nothing was moved. I am going to loosen the belts a bit and see if this might take care of it but like I said the tension on them now is fine. I'll keep you guys updated.
in Forum: C3 Engines
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