C4ProjectCar

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?

DUB

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

C4ProjectCar

I'll check the harmonic balancer.
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.

cudamax

Videos. Post Videos. What else can anyone do, besides Guess and list all the things it could be.
Got to post a video

C4ProjectCar

I'll take a video next time it's squeaking. Sorry about that.

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

Churchkey

Last engine squeak repair was a dry rocker arm.

A long screwdriver will work as a stethoscope. Handle in your ear blade on component.

cudamax

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

C4ProjectCar

And that can be checked just by pulling the valve cover, I assume?
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.

Churchkey

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?

Midnight 85

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.

LannyL81

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.

C4ProjectCar

Thanks for the tip to avoid oil spray when I pull the valve covers and for the tip for listening.
Good to know it could be something other than the cam bearings.

That would be great if it was that easy! The distributor was replaced recently by the PO so maybe it was put back on not quite right. I think the distributor actually hits on the hood a little bit, so I'm guessing that could have an effect.

I know what a harmonic balancer looks like, I just couldn't find something like that on my engine. It should be right on the front of the crank, right? I'll look again.


Thanks again for all the help, guys!

cudamax

Whats going on we can't have a video and we should all just guess at all the possible things that could cause a sound

DUB

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

C4ProjectCar

Cuda, I'll post a video as soon as I can but it doesn't do it until it gets hot. I'll post a video next time I drive somewhere.

Darn, I was hoping your crystal ball would have my answer!

I'm sorry, that's my bad. It's a 1990 base model with the 6-speed.

cgantner5150

Does the squeak go away or change when you disengage the clutch? Throwout or pilot bearing issue?

C4ProjectCar

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.

cgantner5150

I never bothered to find out which one it was - it was all pulled out for stroking and a T5 in my 86. It would squeak in neutral with the clutch pedal released.

C4ProjectCar

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.

C4ProjectCar

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.