vibration at a certain rpm
#1
Staging Lane
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I am looking for ideas please. I bought a car without driving it, had a clutch installed before driving it, finely got the car here and drove it on the interstate. I noticed a vibration that starts at 1800 rpm and goes through 3000 rpm and goes away. It will also do this sitting still with the clutch pushed in or fully engaged in neutral.The seller says he never noticed it while he had it and did not drive the car in this rpm range after the clutch was installed.
What I am wondering is, could this be a flywheel, pressure plate issue or an internal engine issue or something else? What if anything have people experienced like this?
My first thought is to have the clutch and pressure plate checked for balance but I don't know if that vibration would be at a specific rpm and go away or only get worse. What do you think?
What I am wondering is, could this be a flywheel, pressure plate issue or an internal engine issue or something else? What if anything have people experienced like this?
My first thought is to have the clutch and pressure plate checked for balance but I don't know if that vibration would be at a specific rpm and go away or only get worse. What do you think?
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I spoke to an engine builder that through out the possibility of a cracked crank or bent rod. I have a friend that experienced the same problem at about the same rpm. The clutch ended up being out of balance. I hope this is the issue and it is not the engine.
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Do you know what clutch and flywheel are being used? If he reused the stock flywheel and did not balance with his new clutch then this could easily be the problem. Any local machine shop, with a dynamic balancer, should be able to check the unit for proper balance. Or, if you wanted to you could send the parts to me for proper balancing if needed, whether you have our parts or not, and we would be happy to help!
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Thanks Jeremy, It has a steel flywheel which is supposed to be balanced but I thought I would still check it with the clutch. It is the lesser of other potential problems. I guess I was hoping someone would jump in and say they had the same issue and that was what it turned out to be. There are two speed shops around here that can do it for me but I appreciate your offer.
#6
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might not even be clutch related since you didnt drive it pre clutch install
before you go pulling the trans or thinking theres an internal engine problem, pull the belts off and see if its still there. bad bearings in the accessory pulleys (alt, water pump, tensioners, etc) can cause rpm related vibrations
out of curiosity, what speeds shops in thomasville are you referring to
before you go pulling the trans or thinking theres an internal engine problem, pull the belts off and see if its still there. bad bearings in the accessory pulleys (alt, water pump, tensioners, etc) can cause rpm related vibrations
out of curiosity, what speeds shops in thomasville are you referring to