Issue: Sqealing without belts installed

[tomatoes619]

My car, a 99 Civic LX Sedan, recently developed a squealing problem. I thought it was one of the three belts, so i just replaced them all. But it was still there, so I removed the belts one at a time (PS, A/C, Alternator). With no belts installed, the squealing still happens, and it sounds the same.

The noise sounds like a slipping belt, does not happen all the time (most when the engine has more load such as A/C and accelerating from dead/slow speeds), sometimes it's barely there or really loud while idling.

Question is, what might be the problem?

I looked at a diagram of the timing belt assy and though the problem could be either the crankshaft pulley (where the other belts loop around), timing belt tension, bad timing belt (if this makes a noise), or any of the other 4 pulleys (crankshaft, the adjusting pulley, water pump, or camshaft pulley.

But since I've never went that far in repairing my car, I'll leave the guesses to you guys.
Thanks for reading.

 

[lethal6]

Here is the thing...guessing never helps anyone, especially the end user that spends time and money throwing parts at a problem.

You understand that it is damn near impossible to "hear" a sound by reading text over the internet. There is no way we can do this for you. You need to either take it to a mechanic that knows what they are doing with diagnosing properly OR buy a mechanic's stethoscope and find the sound yourself. Then we can tell you how to replace what part is actually bad...instead of just guessing.

 

[RonJ]

^Dead on

buy a mechanic's stethoscope and find the sound yourself.

^ $4 at HFT.

 

[tomatoes619]

Reply

lethal6 thanks very much for the advice. I did not think about that. I'll update when I can

 

[lethal6]

lethal6 thanks very much for the advice. I did not think about that. I'll update when I can

You are welcome.

Please do keep this updated and be careful with the stethoscope around the moving pulleys. They can do some nasty damage if they catch the end of it or your fingers.

 

[tomatoes619]

Update

Update:

I know it's been 2 months but I finally got off my couch.

First, know that I got a stethoscope (cheap OEM brand from AutoZone) and tried using it around the accessories' pulleys. It didn't help. I tried touching the rod as close as it can get to the pulleys, and while I can hear amplified sounds from each or them, it's nothing like a squealing noise. The sounds I hear is basically the same for each 3, which is what you'd probably hear from good bearings. The stethoscope has to actually touch something to be useful, which means it doesn't pick up noise from airwaves.

Anyway, here's a video with sound of it. Note: I'm moving the camera around the engine bay so that maybe it would be louder as I move the camera closer to the source. I noticed that it's loudest when near the exhaust manifold which is also where the PS pump and AC compressor is (I didn't notice this before somehow). The engine is warm at this time and the noise is "better" with a cold start, although it's still there.

https://www.youtube.com/watch?v=XCgIeq9SVeY

On my original post, I know I said that I removed all the accessory belts and still heard the noise (rarely this time), but I left the AC belt dangling around the clutch and the shaft pulley (it could have been spinning somehow). Anyway, as I wait for replies, I'm gonna remove the belts again and test each pulley by wobbling and spinning them by hand and see if I could find something.

Other notes: It seems it usually occurs between 1500 to 2000 RPM but not always. Engaging A/C increases the frequency and volume of the noise. 2 months ago, the noise occurred less times and had a lower volume. It's worse now. My P/S pump was replaced some months ago by an OEM used one from Ebay which I inspected but will inspect again. Out of the topic, there is this knocking noise that can be heard in the video after I turn off the A/C. Is that normal?

 

[xxBLOOD88SHOTxx]

That is a metal on metal noise. It's happening when there is extra load on the engine (lower rpm and more vibration). I would check the exhaust shielding first.

 

[tomatoes619]

Update

I took off the PS belt, AC compressor belt, and alternator belt and the noise is still there, like my original post said.
All pulleys don't wiggle, or make a sound when spun even with a rope.

I looked at the exhaust and it's shields but they don't touch anything. No signs of damage either.

I put my head as close to the noise as possible and it's most loud when my ear is next to the middle of the exhaust manifold. But it's less when I move my head right towards the pulleys. So it could be that the noise is somehow coming from the exhaust manifold or exhaust pipes rubbing against something when the engine is on, and not a pulley. Weird. Like xxBLOOD88SHOTxx said, it could be the shielding. Now, I went under the car and took a video. I think the noise is even louder under the car and it seems it's coming from around the oil pan, next to the exhaust pipes. Now I'll try wiggling the exhaust by hand or with a pipe and see what happens.

https://www.youtube.com/watch?v=qWHeo4KRIBw

I recognize that there is an oil leak maybe from both the oil pan gasket or the oil pump area.

 

[xxBLOOD88SHOTxx]

The shields and the exhaust touch each other.....

 

[tomatoes619]

Update

xxBLOOD88SHOTxx, Thanks man.

It wasn't related to the shielding but when you mentioned exhaust, I started wiggling it. That's when I found the noise. It's something related to where the down pipe connects to the exhaust pipe with the resonator. I unbolted the 2 bolts with springs and looked online to see what parts are supposed to be there. Turns out there is supposed to be a hard flange gasket there. When I separated the 2 pipes, someone apparently used copper RTV instead. Along with the rust, a degraded RTV could be the cause. The bolts, spring, and nuts look new.

These are the pipes I'm talking about.

Anyway, I left the pipes unbolted and separated and there was no noise. I tried everything I knew to try to replicate the noise, but no noise.

So I bought the gasket and installed it. The noise is definitely gone.