Engine Squeaking
Thread Starter
Drifting
Joined: Jul 2014
Posts: 1,426
Likes: 46
From: Lynchburg, VA
Engine Squeaking
I've been having a persistent squeak after my engine warms up that is pretty annoying and, quite frankly, embarrassing. It seems to go away - or becomes less noticeable - at higher RPMs than idle. I thought it was the smog pump or the belt tensioner (both items needed to be replaced anyway) so I replaced those, and the squeak remained.
I decided I'd narrow my search by removing the belt after it starts squeaking to see if it is or is not the belt-driven accessories. Unfortunately, the squeak remained.
From what I've heard, the camshaft can cause a squeak with worn bearings (which I know it has). I can't think of anything else in the engine compartment that could squeak with the belt off. Is my diagnosis correct?
I decided I'd narrow my search by removing the belt after it starts squeaking to see if it is or is not the belt-driven accessories. Unfortunately, the squeak remained.
From what I've heard, the camshaft can cause a squeak with worn bearings (which I know it has). I can't think of anything else in the engine compartment that could squeak with the belt off. Is my diagnosis correct?
Last edited by C4ProjectCar; Sep 7, 2014 at 04:30 PM.
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,753
From: Charlotte NC
The outer ring on the harmonic balancer has slid back and it contacting the timing chain cover. I had this occur once.
The inspection cover for your torque converter is contacting the flywheel or crank. Usually does it right off the bat when cranked.
Have you tried to find the noise with a stethoscope.
DUB
The inspection cover for your torque converter is contacting the flywheel or crank. Usually does it right off the bat when cranked.
Have you tried to find the noise with a stethoscope.
DUB
Thread Starter
Drifting
Joined: Jul 2014
Posts: 1,426
Likes: 46
From: Lynchburg, VA
The outer ring on the harmonic balancer has slid back and it contacting the timing chain cover. I had this occur once.
The inspection cover for your torque converter is contacting the flywheel or crank. Usually does it right off the bat when cranked.
Have you tried to find the noise with a stethoscope.
DUB
The inspection cover for your torque converter is contacting the flywheel or crank. Usually does it right off the bat when cranked.
Have you tried to find the noise with a stethoscope.
DUB
Mine's a manual, so no torque converter.
I haven't yet; I don't have a stethoscope.
Thanks for the help!
EDIT: Do stock cranks have a harmonic balancer with an inner and outer ring? I thought the HB was the disc with the timing mark on it, which is a solid metal disk, not the kind with the rubber separating the two layers.
Last edited by C4ProjectCar; Sep 7, 2014 at 08:46 PM.
Thread Starter
Drifting
Joined: Jul 2014
Posts: 1,426
Likes: 46
From: Lynchburg, VA
Until then, here is what I've found boiled down:
- Squeaks only when hot
- Doesn't squeak at RPMs above idle
- Still squeaks with the serpentine belt off
- Squeak sounds like it's coming from below the intake manifold
- I know my cam bearings are worn
Burning Brakes
Joined: Mar 2013
Posts: 1,131
Likes: 5
From: Illinois/Wisconsin Line
Sounds like you already know
Squeaks only when hot
Doesn't squeak at RPMs above idle
Still squeaks with the serpentine belt off
Squeak sounds like it's coming from below the intake manifold
I know my cam bearings are worn
Squeaks only when hot
Doesn't squeak at RPMs above idle
Still squeaks with the serpentine belt off
Squeak sounds like it's coming from below the intake manifold
I know my cam bearings are worn
Thread Starter
Drifting
Joined: Jul 2014
Posts: 1,426
Likes: 46
From: Lynchburg, VA
Hmm, good tip. Thanks.
Well, I just want to see if there's anything else that could be causing it so I can be sure to get rid of this horrible squeak as soon as possible. I also found very few reports of worn cam bearings causing a squeak.
Last edited by C4ProjectCar; Sep 8, 2014 at 02:29 AM.
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Melting Slicks
Joined: Sep 2008
Posts: 2,376
Likes: 111
From: Cherokee National Forest TN
Yep, pull a cover if the problem is not there pull the other cover. If starting the engine with the covers off: Normally rocker arm clips are used to keep oil spray to a minimum I know you do not have them. Cut 2 of 6-8" tall lengths of cardboard, place them in the head between the valve springs & valve cover seat rail. Don't rev the engine unless you want to oil the tire thread.
Another DIY listening device: A length of vacuum or fuel hose. Cotton in one ear, end of hose in the other ear, search.
Doubt the cam bearings are the squeak cause.
Is your oil pressure still OK? No knocks, rattles, mechanical noise other than the squeak?
Another DIY listening device: A length of vacuum or fuel hose. Cotton in one ear, end of hose in the other ear, search.
Doubt the cam bearings are the squeak cause.
Is your oil pressure still OK? No knocks, rattles, mechanical noise other than the squeak?
Le Mans Master
Joined: May 2004
Posts: 5,866
Likes: 60
From: Hellinois
Finalist 2020 C4 of the Year - Modified
I had a squeak like that once that was coming from a rebuilt crate engine. I was all over that engine and transmission with no luck. Finally someone suggested the distributor may be just a little off center due to someone assembling the engine with more taken off one side of the deck or more likely, one shaved head and the other one not shaved which in effect cocked the intake manifold. Loosen the dist. hold down & see if the noise goes away. If it does, take a dist. gasket and cut it in half and place it along with a complete gasket under the dist. You will have to move it around until it is in the correct position to hold the dist. straight. Sounds weird I know but it is fact.
Melting Slicks
Joined: Nov 2005
Posts: 3,323
Likes: 142
From: Green Valley Arizona
The harmonic balancer is not a soild metal disc. There is a solid inner portion and a solid outer ring which is held to the inner ring by a band of rubber. The rubber will fall-out over the years and the outer ring will begin to slip and contact the timing cover, the crank pulley, etc.
Also since the timing marks on on the outer ring, if it slides, then setting engine timing becomes only a guess.
Also since the timing marks on on the outer ring, if it slides, then setting engine timing becomes only a guess.
Thread Starter
Drifting
Joined: Jul 2014
Posts: 1,426
Likes: 46
From: Lynchburg, VA
Yep, pull a cover if the problem is not there pull the other cover. If starting the engine with the covers off: Normally rocker arm clips are used to keep oil spray to a minimum I know you do not have them. Cut 2 of 6-8" tall lengths of cardboard, place them in the head between the valve springs & valve cover seat rail. Don't rev the engine unless you want to oil the tire thread.
Another DIY listening device: A length of vacuum or fuel hose. Cotton in one ear, end of hose in the other ear, search.
Doubt the cam bearings are the squeak cause.
Is your oil pressure still OK? No knocks, rattles, mechanical noise other than the squeak?
Another DIY listening device: A length of vacuum or fuel hose. Cotton in one ear, end of hose in the other ear, search.
Doubt the cam bearings are the squeak cause.
Is your oil pressure still OK? No knocks, rattles, mechanical noise other than the squeak?
Good to know it could be something other than the cam bearings.
I had a squeak like that once that was coming from a rebuilt crate engine. I was all over that engine and transmission with no luck. Finally someone suggested the distributor may be just a little off center due to someone assembling the engine with more taken off one side of the deck or more likely, one shaved head and the other one not shaved which in effect cocked the intake manifold. Loosen the dist. hold down & see if the noise goes away. If it does, take a dist. gasket and cut it in half and place it along with a complete gasket under the dist. You will have to move it around until it is in the correct position to hold the dist. straight. Sounds weird I know but it is fact.
The harmonic balancer is not a soild metal disc. There is a solid inner portion and a solid outer ring which is held to the inner ring by a band of rubber. The rubber will fall-out over the years and the outer ring will begin to slip and contact the timing cover, the crank pulley, etc.
Also since the timing marks on on the outer ring, if it slides, then setting engine timing becomes only a guess.
Also since the timing marks on on the outer ring, if it slides, then setting engine timing becomes only a guess.
Thanks again for all the help, guys!
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,753
From: Charlotte NC
I broke my crystal ball when I was kid...or I would already know what it was. And the company that sold me an AUTHENTIC Harry Potter magic wand (that way I KNOW it will work) keeps telling me it is in the mail.
ALSO.....
I had to guess on the harmonic balancer comment...because you did not state your year model.
Always post your year model.
DUB
Thread Starter
Drifting
Joined: Jul 2014
Posts: 1,426
Likes: 46
From: Lynchburg, VA
UHHHH...guess. Kinda like playing 'pin the tail on the donkey'.
I broke my crystal ball when I was kid...or I would already know what it was. And the company that sold me an AUTHENTIC Harry Potter magic wand (that way I KNOW it will work) keeps telling me it is in the mail.
ALSO.....
I had to guess on the harmonic balancer comment...because you did not state your year model.
Always post your year model.
DUB
I broke my crystal ball when I was kid...or I would already know what it was. And the company that sold me an AUTHENTIC Harry Potter magic wand (that way I KNOW it will work) keeps telling me it is in the mail.
ALSO.....
I had to guess on the harmonic balancer comment...because you did not state your year model.
Always post your year model.
DUB
I'm sorry, that's my bad. It's a 1990 base model with the 6-speed.
Thread Starter
Drifting
Joined: Jul 2014
Posts: 1,426
Likes: 46
From: Lynchburg, VA
Earlier I thought I saw some correlation between the clutch and the squeak, although recently there has been no relationship. It stays the same with the clutch pedal in or out.
Thread Starter
Drifting
Joined: Jul 2014
Posts: 1,426
Likes: 46
From: Lynchburg, VA
As I was going through the process of burping the cooling system, I heard a new squeak. This one was far higher-pitched (my dad couldn't even hear it) and had a less regular repetition. Unfortunately, due to some issues while burping it, I wasn't able to get a video.
Thread Starter
Drifting
Joined: Jul 2014
Posts: 1,426
Likes: 46
From: Lynchburg, VA
Unfortunately (fortunately?) the squeak has quieted down to the point where it isn't recognizable on a video. I'll just wait until the rebuilt and then let you know if that fixed it.