Engine vibrations..

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boeing7873
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Engine vibrations..

Post by boeing7873 »

My engine has been slowly developing high frequency engine vibrations. Those that make your joints tingle. Engine runs great otherwise. Any thoughts? Engine mount checks are next on my list.
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rmel
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Re: Engine vibrations..

Post by rmel »

No one chimed in[SMIRKING FACE] well here’s a couple of thoughts. Maybe something went out of balance. Does this occurr when in neutral. When the clutch is disengaged. At idle or at a particular speed? Mane you could tie the frequency of the vibration to the engine RPM. Is it 1 for 1. Or a multiple of rpm. Might lead to some clues.


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Jimm391730
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Re: Engine vibrations..

Post by Jimm391730 »

Two things come to mind:
1. The driveshaft to the front axle is out of balance. The front end of the driveshaft is attached to the front diff, 4x4 is engaged by connecting the rear end of the shaft to the transfer case. This end has a pin that spins in a bushing so that if you are spinning the rear wheels but the front are not turning (stuck, for example) the difference in speeds shows up between the pin and bushing. Pulling the 4x4 lever slides the collar over the splines on the shaft and can sometimes change the balance of the shaft. If you drive at highway speeds and feel the vibration, pull the green lever and see if the vibration changes - it won't necessarily go away, but it may be somewhat different and this points to driveshaft vibration. Remember, at 60mph this shaft is spinning at roughly 4400 rpm! Search for "lightened, balanced driveshaft" for more info on how to solve this problem.
2. The fan may be out of balance. This will obviously change with engine revs. Maybe part or all of a blade is missing? Mud stuck to it? Etc.

But I will go out on a limb and suggest that #1 is the culprit.
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4x4Pinz
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Re: Engine vibrations..

Post by 4x4Pinz »

Check all engine mounts and the team mount. Back in the early days were used to put a small piece of rubber hose over the travel stop pin at the trail mount. When the mount would get warn it would allow the pin to rub against the bracket and send vibrations from the drive train to the body.
pinzinator
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Re: Engine vibrations..

Post by pinzinator »

Perhaps a plug or fuel stop solenoid failed.
boeing7873
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Re: Engine vibrations..

Post by boeing7873 »

pinzinator wrote:Perhaps a plug or fuel stop solenoid failed.
Ahhhh... But engine would run rough at idle if solenoid failed. What do you mean by plug?

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boeing7873
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Re: Engine vibrations..

Post by boeing7873 »

rmel wrote:No one chimed in[SMIRKING FACE] well here’s a couple of thoughts. Maybe something went out of balance. Does this occurr when in neutral. When the clutch is disengaged. At idle or at a particular speed? Mane you could tie the frequency of the vibration to the engine RPM. Is it 1 for 1. Or a multiple of rpm. Might lead to some clues.


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This is definitely engine. Clutch in or out does not make an difference. It is a very high freq vibration. Based on comments here, if I had to bet, I would say these are natural but some mount has failed to the point where metal to metal is in contact and vibrations now travel to body.


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boeing7873
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Re: Engine vibrations..

Post by boeing7873 »

4x4Pinz wrote:Check all engine mounts and the team mount. Back in the early days were used to put a small piece of rubber hose over the travel stop pin at the trail mount. When the mount would get warn it would allow the pin to rub against the bracket and send vibrations from the drive train to the body.
If I had to bet... This would explain. I'll check.

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boeing7873
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Re: Engine vibrations..

Post by boeing7873 »

Jimm391730 wrote:Two things come to mind:
1. The driveshaft to the front axle is out of balance. The front end of the driveshaft is attached to the front diff, 4x4 is engaged by connecting the rear end of the shaft to the transfer case. This end has a pin that spins in a bushing so that if you are spinning the rear wheels but the front are not turning (stuck, for example) the difference in speeds shows up between the pin and bushing. Pulling the 4x4 lever slides the collar over the splines on the shaft and can sometimes change the balance of the shaft. If you drive at highway speeds and feel the vibration, pull the green lever and see if the vibration changes - it won't necessarily go away, but it may be somewhat different and this points to driveshaft vibration. Remember, at 60mph this shaft is spinning at roughly 4400 rpm! Search for "lightened, balanced driveshaft" for more info on how to solve this problem.
2. The fan may be out of balance. This will obviously change with engine revs. Maybe part or all of a blade is missing? Mud stuck to it? Etc.

But I will go out on a limb and suggest that #1 is the culprit.
Your #1 suggestion is only for vibrations while moving I assume. If truck is stopped, these should go away, right?

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undysworld
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Re: Engine vibrations..

Post by undysworld »

Yes. The out-of-balance driveshaft problem only occurs when moving.
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boeing7873
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Re: Engine vibrations..

Post by boeing7873 »

I think it was all psychological. I assume these vibrations are normal for a Pinz.
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boeing7873
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Re: Engine vibrations..

Post by boeing7873 »

I think it was all psychological. I assume these vibrations are normal for a Pinz. ://
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