New Clutch Vibration
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New Clutch Vibration
I took my 1993 F-150 with 106,000 miles to a local garage to have the clutch rebuilt because the slave cylinder had been leaking. Since they completed the total rebuild of the clutch the motor has a slight vibration that is almost tolerable, but is the worst when the motor is just above idle. The vibration occurs all the time and operating the clutch, shifting or driving doesn't affect it.
I took it back to the shop and they thought the pressure plate was out of balance and they reinstalled another new clutch kit. It still has the same vibration and when I returned it they tuned the motor and said it helped, but it did't. They tell me it is an internal engine problem that must have been there all along and they didn't drive it before they installed the clutch and don't know that it didn't vibrate before.
I tried to tell them that maybe the flywheel is out of balance either when it was machined or maybe installed improperly but they said that is not the problem.
Does anybody have any ideas on what could be causing this.
Thanks,
Dave
I took it back to the shop and they thought the pressure plate was out of balance and they reinstalled another new clutch kit. It still has the same vibration and when I returned it they tuned the motor and said it helped, but it did't. They tell me it is an internal engine problem that must have been there all along and they didn't drive it before they installed the clutch and don't know that it didn't vibrate before.
I tried to tell them that maybe the flywheel is out of balance either when it was machined or maybe installed improperly but they said that is not the problem.
Does anybody have any ideas on what could be causing this.
Thanks,
Dave
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New Clutch Vibration
That's a tough one. Starting with the least, check your motor mounts, maybe they started acting up with the "taking the trans off" and all that stuff. You can just watch your motor idle to see if its shaking too much. As a long shot, I used to see some flywheels with weights on them (in older cars anyways), maybe one of those came off (that may not be true for newer trucks, like yours, seems like they balance them without adding weights these days). A terrible possiblity is they didn't support your trans properly when taking it off and bent your input shaft. You'll see oil leaking from your rear seal pretty soon if that's the case. Some of the other mechanics on this site will probaly have some more suggestions.
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New Clutch Vibration
I checked the engine mounts and they seem ok. I don't think the flywheel has any balance weights that might fall off. The bent input shaft seems like a likely cause. Would the vibration change when the clutch is disengaged when in gear and the input shaft stops spinning? The vibration doesn't change when I do this. I looked for leakage at the rear main seal, which was replaced, and didn't see any yet. It's only 3 weeks old. I would think the pilot bearing would't last long if the shaft is bent.
Is there an easy way to check to see if the shaft is bent.
Thanks,
Dave
Is there an easy way to check to see if the shaft is bent.
Thanks,
Dave
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New Clutch Vibration
The shaft always turns as long as the motor turns. I changed a truck tranmission and lost all support and left the trans hanging from the shaft (you know how it is working by yourself) and it didn't hurt the shaft at all. That's why I don't want to send you too far down this theory.
So it can't be driveshaft or just a bad miss in the motor?
So it can't be driveshaft or just a bad miss in the motor?
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New Clutch Vibration
The shop originally told me the motor was missing or the vibration damper was bad. They put it on the scope and found a misfire from a clogged injector. They cleaned the injector and the engine runs great but the vibration didn't change. The truck never had the vibration before they installed the clutch so I find it hard to believe the damper would go out at the same time.
The vibration occurs all the time even when the truck is sitting still, so I know its not the drive shaft. It even vibrates when your coasting in gear without your foot on the gas. It is so constant that it just seems like something is out of balance. The only thing that affects it is reving the motor. I have just recently noticed a chirping sound that has the same rhythm as the vibration coming from underneath the truck. Could this be the pilot bearing because of a bent input shaft? It does have the lightweight Mazda transmission which probably has a smaller input shaft which may be easier to bend.
The shop said they would install a different brand of clutch kit if I'm not happy so I guess I'll look at it when it's apart to check the input shaft. I'm sure it's something they didn't check.
Thanks,
Dave
The vibration occurs all the time even when the truck is sitting still, so I know its not the drive shaft. It even vibrates when your coasting in gear without your foot on the gas. It is so constant that it just seems like something is out of balance. The only thing that affects it is reving the motor. I have just recently noticed a chirping sound that has the same rhythm as the vibration coming from underneath the truck. Could this be the pilot bearing because of a bent input shaft? It does have the lightweight Mazda transmission which probably has a smaller input shaft which may be easier to bend.
The shop said they would install a different brand of clutch kit if I'm not happy so I guess I'll look at it when it's apart to check the input shaft. I'm sure it's something they didn't check.
Thanks,
Dave
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The shop originally told me the motor was missing or the vibration damper was bad. They put it on the scope and found a misfire from a clogged injector. They cleaned the injector and the engine runs great but the vibration didn't change. The truck never had the vibration before they installed the clutch so I find it hard to believe the damper would go out at the same time.
The vibration occurs all the time even when the truck is sitting still, so I know its not the drive shaft. It even vibrates when your coasting in gear without your foot on the gas. It is so constant that it just seems like something is out of balance. The only thing that affects it is reving the motor. I have just recently noticed a chirping sound that has the same rhythm as the vibration coming from underneath the truck. Could this be the pilot bearing because of a bent input shaft? It does have the lightweight Mazda transmission which probably has a smaller input shaft which may be easier to bend.
The shop said they would install a different brand of clutch kit if I'm not happy so I guess I'll look at it when it's apart to check the input shaft. I'm sure it's something they didn't check.
Thanks,
Dave
The vibration occurs all the time even when the truck is sitting still, so I know its not the drive shaft. It even vibrates when your coasting in gear without your foot on the gas. It is so constant that it just seems like something is out of balance. The only thing that affects it is reving the motor. I have just recently noticed a chirping sound that has the same rhythm as the vibration coming from underneath the truck. Could this be the pilot bearing because of a bent input shaft? It does have the lightweight Mazda transmission which probably has a smaller input shaft which may be easier to bend.
The shop said they would install a different brand of clutch kit if I'm not happy so I guess I'll look at it when it's apart to check the input shaft. I'm sure it's something they didn't check.
Thanks,
Dave
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