Rattling noise from engine, HELP
CF Veteran
Joined: Aug 2011
Posts: 10,489
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From: Nor-Cal Coast
Year: 90,84
Model: Cherokee
Engine: 4.0,2.5
Just putting a wrench on the crank pulley bolt would be a supper easy start. (3/4, 19mm ?)See that it is snug. Loosening the belt and feeling everything including the crank pulley is an idea also. Just an easy start.
Sure sounds like there is a vacuum leak as well.
Gently revving it a few times might help the video...I suppose a pushrod off wouldn't sound much different, but a bad rod might bang harder as you gas it.
Sure sounds like there is a vacuum leak as well.
Gently revving it a few times might help the video...I suppose a pushrod off wouldn't sound much different, but a bad rod might bang harder as you gas it.
Last edited by DFlintstone; Dec 26, 2012 at 12:06 AM.
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Model: Cherokee
CF Veteran
Joined: Aug 2010
Posts: 8,357
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From: Canton, MI
Year: 1999
Model: Cherokee
Engine: 4.0
Do you have a video of this being accomplshed that you could post here?
CF Veteran
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From: Wisconsin
Model: Cherokee
CF Veteran
Joined: Mar 2011
Posts: 2,570
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From: California
Year: 1992
Model: Cherokee
Engine: 4.0 HO
Anyways, back to the OP's problem. This would be a good starting point. https://www.cherokeeforum.com/f51/ho...ocking-125547/
Check the bolts and report back.
Check the bolts and report back.
CF Veteran
Joined: Nov 2011
Posts: 2,381
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From: SoCal
Year: 1989
Model: Cherokee
Engine: 4.0
You can rule out your harmonic balancer with just a flashlight. It's the lower-most pulley and it's attached directly to the front crank output. If it's going bad you'll see rubber bits barfing [technical term] out the face of the pulley. This is what a bad harmonic balancer looks like and if it's left to it's own devices, it will detach and go through your radiator or timing belt cover. If that noise is coming from the HB then it could catastrophically fail at any time. If the sound is coming from the front of your engine and it's not the harmonic balancer then it could be a wrist pin, a bad con rod/bearing, or a fractured piston skirt and will require removing the oil pan to inspect the crank and check for piston bits in the oil.
Thread Starter
CF Veteran
Joined: Aug 2010
Posts: 1,085
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From: Fountain Inn, SC
Year: 1988
Model: Comanche (MJ)
Engine: I6 4.0L
You can rule out your harmonic balancer with just a flashlight. It's the lower-most pulley and it's attached directly to the front crank output. If it's going bad you'll see rubber bits barfing [technical term] out the face of the pulley. This is what a bad harmonic balancer looks like and if it's left to it's own devices, it will detach and go through your radiator or timing belt cover. If that noise is coming from the HB then it could catastrophically fail at any time. If the sound is coming from the front of your engine and it's not the harmonic balancer then it could be a wrist pin, a bad con rod/bearing, or a fractured piston skirt and will require removing the oil pan to inspect the crank and check for piston bits in the oil.
::CF Moderator::
Joined: Aug 2011
Posts: 43,971
Likes: 1,579
From: Prescott, Az
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
You can rule out your harmonic balancer with just a flashlight. It's the lower-most pulley and it's attached directly to the front crank output. If it's going bad you'll see rubber bits barfing [technical term] out the face of the pulley. This is what a bad harmonic balancer looks like and if it's left to it's own devices, it will detach and go through your radiator or timing belt cover. If that noise is coming from the HB then it could catastrophically fail at any time. If the sound is coming from the front of your engine and it's not the harmonic balancer then it could be a wrist pin, a bad con rod/bearing, or a fractured piston skirt and will require removing the oil pan to inspect the crank and check for piston bits in the oil.
I stole your photo. Thanks in advance.
::CF Moderator::
Joined: Aug 2011
Posts: 43,971
Likes: 1,579
From: Prescott, Az
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
