Random sounds coming from belt drive? Already replaced SC coupler...

It is most loud on startup and after a few minutes of idling, it seems to go away for the most part. It sounds like something rattling/popping. I just changed the SC coupler with one from Intense. It has done it before and after this change. I noticed the SC tensioner doesn't move that much...I mean the pulley moves just fine, but the actual spring loaded parts don't seem to move much while the car is running. The arrow is pointing to the 2nd to the last line (the two lines that are really close together). Both belts were replaced when doing the coupler. I used new Gatorback belts, and they both feel nice and tight on the car. I did spin all the pulleys with both belts off, and they all seemed fine. The water pump pulley, however, I can grab it and "feel" it move just barely in and out. I mean, such little movement that I can't even see it. I can hear it/feel it though. Any thoughts?

Btw, I do apologize for the several posts I've made lately. I just acquired this car (95 Riv) and am trying to fix it up.

Will: when my water pump pulley gave out, it was moving quite a bit. There's a video in this post:

https://rivperformance.editboard.com/t8340p15-write-up-water-pump-series-ii-sc

Based on your description, I don't think the pump is the problem. One way to track down these noises is to (carefully!) use a mechanic's stethoscope to listen to the pulleys with the car running. For best results, use the type with the funnel amplifier attachment, not the metal probe. Best of luck.

AA wrote:

For best results, use the type with the funnel amplifier attachment, not the metal probe. Best of luck.

X2 on the funnel type. The front of our engines make a shit-ton of noise. Listening to it with the metal probe style will lead you to replace things that don't need replacing if you don't know any better.

Here's a vid. For some reason my phone picked up some weird hissing sound, but I didn't actually hear it myself from the car...just on video playback. But you can hear the rattling/clanking sound pretty clear I think.



Also, thanks for the heads up about the stethoscope. That is something I will look into.

Just turn the car upside down and shake the marbles out of it......

I have no idea what that noise is. I can't even point in a direction with that vid.

Sounds like a rusted bearing or SC rotor banging, but hard to tell from a distance with a lap top computer with lousy speaker. Could be alternator, pulley, etc.. I know its a pain, but remove the SC serpentine belt, and then run the car and see if you still hear it. That may help to isolate the problem. When the engine is cool, you can also run for a few seconds without the acc belt on. That would at least confirm it is an accessory problem and not an engine problem. I have heard that SC belt tensionors that are stiff and do not flex can put undue stress on the SC bearings and cause a failure there. For my 05 Park Ave Ultra, it was a cheap part and and easy replacement.

AA wrote:

One way to track down these noises is to (carefully!) use a mechanic's stethoscope to listen to the pulleys with the car running..

If you don't have a mechanic's stethoscope, you could always try a redneck stethoscope, which is just a piece of cut hose...

Don't judge me. :-[

gunmetalRED wrote:

AA wrote:

One way to track down these noises is to (carefully!) use a mechanic's stethoscope to listen to the pulleys with the car running..

If you don't have a mechanic's stethoscope, you could always try a redneck stethoscope, which is just a piece of cut hose...

Don't judge me. :-[

No judgement here. I'll just put it next to my redneck creeper aka large piece of cardboard.

The alternator is brand new (not even reman'd) because the old one was noisy (bearings)...that got rid of that particular noise, lol. What should the SC pulley feel like if you spin it by hand? After reinstalling with new gaskets, coupler, and oil...I could easily spin it by hand (could before all the work was done, too). It wouldn't spin freely though, like the idler pulleys for example, it would only "turn" as I turned it...if that makes any sense. There was just a very slight amount of resistance when doing this. The alternator, for example, I could give the pulley a good spin and it would turn freely on its own for quite a while before stopping. Not the case with the SC pulley. I'm new to these cars, and SC engines in general, so I'm trying to learn as much as I can as I go.

The tensioner, I am definitely going to replace. I can actually move it via the bolt and it won't spring back unless I release a lot of tension...and as I said, the arrow indicator is on the 2nd to the last line. I hope that maybe it's just the tensioner and I can move on with my life lol. Also, I wish i had some kind of indicator of whether or not the SC was working like it should. I don't hear the "whine" that most people talk about except for a slightly audible one at idle while sitting in the car. But, when I drive, it seems like it has plenty of power. And if I give it enough throttle (probably 60% or greater) it takes off like a bat out of hell and pushes me back in the seat just a little bit. Sound about right? Oh, and the previous owner neglected to use premium for the 4 or so months they had it. It still has 87 in it...haven't had the chance to take it to the gas station yet to put the good stuff in.

Btw, on the 95, it seems as though the supercharger tensioner is just the standard bolt in style. I've seen another one for the accessory drive that has the coolant lines going through it and the two coolant elbows...does the 95 utilize this same tensioner for the accessory drive or does it use the standard single-bolt tensioner? They apparently sell just the alt tensioner without the coolant plumbing. I figure I might replace that too if it's easy enough. I hear these tensioners are pretty dramatic when they fail.

gunmetalRED wrote:

If you don't have a mechanic's stethoscope, you could always try a redneck stethoscope, which is just a piece of cut hose...

Don't judge me. :-[

Nothing wrong with it - a piece of hose works very well! I have the 'metal probe' stethoscope and for cases like this where it's nice to have a 'funnel' stethoscope a piece of hose is a fantastic substitute.

I happened to glance at my HB and noticed there is a very thin but defined crack in the rubber going around the entire thing, on the outside edge (where it meets the grooved metal pulley part). In the video I uploaded, the sound appears to get louder as I put the camera further down into the engine bay (towards the A/C bypass and HB)...I'm guessing this might be the culprit? I just replaced the SC tensioner with a new one, belt seems to fit much better. I wonder how much time I have left on the HB? I really don't know if I can afford or do the replacement myself.

How do I know which design I need? There is a "1st design" and a "2nd design" ??

95 Supercharged

billfrank85 wrote:

How do I know which design I need? There is a "1st design" and a "2nd design" ??

95 Supercharged

I'm afraid the only way to know is to take the existing one off and look. The first design has a small weight opposite the key way, and the second has a larger weight. 95 was a weirdly mixed bag, there's really to rhyme or reason to what got put on when.