Hey all,

I have had an issue with my motor making a whinning or zinging noise that is directly proportional to the engine speed (RPMs). NO, it is not the supercharger whine! It happens whether there is load or no load on the engine. It all started when I did a supercharger pulley upgrade to a 15% reduction Alta pulley. The motor made no funny noises prior, just some good ol' sexy supercharger whine... I followed all the correct procedures, installed a new, correct sized Gates belt and replaced the belt tensioner with an AC Delco unit while I was at it. I made sure the pulley was pushed onto the supercharger snout all the way and it lines up with the belt path as it should. I could spin it freely with no rubbing or anything like that. Ever since that install in June of 2017 the whinning or zinging noise has persisted and as of recently has been getting louder. The noise is definitely coming from that area of the motor as I have removed the right front wheel arch liner and started the motor to listen to it before but could not find the culprit. Since then, I have replaced the belt a second time thinking that was the issue and I did a supercharger oil service as well, when I did my clutch this winter. My car is a 2002 MCS with about 79k miles. My guess is that it is either the idler pulley or the crank shaft pulley. Has anybody else experienced this? If so, what's the magic fix? I can post a video clip of the noise if needed. Thank you for any help or suggestions!

 

In my experience, there was a metallic shrill that was proportional to the engine RPM's, which turned out the be the Idler Pulley. If there was an issue with the Crank Pulley, I would imagine there would be a burning smell.

 

gumbedamit, thank you for the reply! What you are describing is exactly what I am experiencing. Just to clarify, the reason you would smell the burning smell if it was the crank pulley is because of the fluid leaking out of it, correct?

 

I'm not certain the fluid would cause the burning smell, but the rubber deteriorating would cause the burning smell being spun at those high RPM's. Idler pulleys are under $40, I would start there.

 

Hey everyone,

I purchased the idler pulley thinking that was the issue and just installed it and the problem continues... The idler pulley was a little rough but it still spun freely. I have attached a link to a video clip of the sound. Any thoughts?

https://drive.google.com/file/d/1pWz...ew?usp=sharing

 

If you look closely, you can see the bolt of my crankshaft pulley slightly wobbling as it appears to be off center. Signs of a bad crankshaft pulley?

 

Going to move you to the Stock Problems/Issues area.

1.) A home made car stethoscope can be made by using a rubber hose that you then point toward a specific area of the engine to determine where noises are coming from.
2.) On the crank pulley, sometimes you will have a rubber residue on the engine cover next to the pulley or you are able to push the pulley in so that it contacts the engine. If the pulley's rubber core is bad and the unit is spinning on itself, the alternator will not charge correctly.
3.) Have you checked the tensioner to see if there are any rub marks on it?

 

Maybe I'm deaf, I don't hear anything out of the ordinary. When I get home I'll put on some headphone and listen again.

 

Thank you for the reply Whine! I will employ the hose trick when I get a chance tomorrow during my break between classes. Your point #2 sounds likely because I have been having electrical issues with my car were my battery seems to be charged on some days and dead on others. My car will struggle to start on a cold morning start-up, but once worm it will start fine. When I say trouble starting, I mean it cranks over very very slow almost to the point where it won't crank anymore. When I throw it on the tender over night it is completely fine. (battery new in Feb 2018 - Interstate) Although, if it was slipping wouldn't that mean my boost pressure would be low? Right now it is about 14.5 lbs @ 6500 RPM-ish with a 15% reduction pulley, that seems about right. I will double check on the belt rubbing the tensioner when I dig back into it tomorrow!

 

Could be the alternator as your boost sounds good.

 

Update Time:

After taking the car back apart after class today I did some searching around and this is what I found:

1.) All of the pulleys moved with relative ease (besides the supercharger and crank pulley... obviously) and they all felt smooth when spinning. No grittiness or grinding (video in google drive folder - "Spinning ALL Pulleys")
2.) The rubber on my crank shaft pulley seemed to be in good shape. I'm not sure if their is any rubber besides the stuff that is exposed on the front of the pulley (video in google drive folder - "Crank Pulley Inspection / Knocking")
3.) The crank pulley makes a knocking noise when I rock it si. The movement is subtle but it is definitely making metal on metal contact. If I can move it by hand then I'm sure the motor under stress has no problem. You can hear it in the new videos that I posted into the google drive folder listed here: (https://drive.google.com/drive/folde...2F?usp=sharing)
4.) I couldn't find any extra hose laying around but I did put my ear close to the belt path and it sounds louder up near the top of the motor by the valve cover but that is by no means scientific. The sound is loud period...
5.) The belt tensioner looked fine and I did not see where there could have been any rubbing. I even removed the belt completely to take a look at it and it still looks just like it did when I put it on 9 months ago.

I will try to get a multimeter soon or maybe run to the local auto parts store to test the voltage and current coming out of the alternator to see if something is funny there. As far as I can tell though, it seems like it is spinning just fine and is dead silent.

 

I watched the video that you rock the damper by hand. Man! If you can move it and it made that metal to metal contact sound, your pulley is more than toasted. There is a ton of rubber inside the back side, and they must be so rotted. Find $350 and get a ATI Superpulley.

 

Thank you pnwR53S, I have read your mini story front to back and I'm a fellow Portlandian, so I appreciate your $0.02. I figured that was the answer I was going to get on the crank pulley being toasted, but being a broke college student makes it hard to throw money at a $350 pulley. I understand that everyone on here says do the ATI and it is the bread and butter of this forum but what are yours (or ANYONE else's) thoughts on the PRW fluid filled pulley offered by RMW among others. I understand that the difference is only $100 but that is groceries for two weeks!

 

BTW, I suspect the metal to metal contact sound you hear when rocking the pulley is the pulley coming into contact with the timing chain cover.

When I recently in the market for a pulley damper, I briefly considered the PRW fluid filled as it is over $100 cheaper. There are a few owners installed one and there seems to be no negative report. I have some reservation with the idea of fluid filled. While they say it is viscous silicone fluid I don't feel comfortable with the idea.

"PRW Fluid Dampers are made with an internal steel intertia ring that is surrounded by a high viscosity silicone gel. The internal intertia ring "floats" in the silicone gel to combat the engine harmonics at all RPM ranges. Crankshaft and bearing life is significantly improved and safely increases torque and horsepower."

I see it a bit like my high speed spin dry of my front loading washing machine, with initially a unbalance load. As it spins up the load distribute itself and eventually reach near perfect balance at 1500 RPM. The problem is there are long period of time it is far from balance. I know the PRW damper is much more balance to begin with.

As there has never been any failure reported with ATI I decided it is not worth the risk for something so important over $120.

 

 

I mainly use the car as a daily driver. I occasionally go on spirited drives but only on rare occasions.

 

I ended up biting the bullet and going with the ATI. It is on its way and I will update you guys if this solves my problem once I have it installed. Thank you all for the help and suggestions thus far!

 

Update time! I have replaced my old harmonic balancer with a new ATI Super Damper and wow am I impressed! I mean holy smokes... the difference in motor vibration, smoothness in reving, idling and everything in between is seriously night and day. Although, I am a little disappointed to say that the mystery noise is still there. Now I know it has nothing to do with the pulley and I have nothing bad to say about the ATI pulley. With my $100 Ryobi impact wrench, the install was a breeze. The only bummer is that I just spent $375 to replace a pulley, front main seal, and new bolt just to have the same persisting issue. I am sure glad I got a new seal because the old one had wiggled itself half way out! With that being said, have been doing some more reading and I am beginning to think it may be a bad gear mesh located internally in the SC. Something like this: . When I did my supercharger oil service this last winter, that side of the SC was bone dry; not even a drop of oil came out. Now, when I did first start my car back up after doing the service and my clutch this last winter the noise was still there and there was definitely oil in there. Any thoughts?

 

Can you make a video with care to capture the sound you think is the SC problem? Without it you can get all sorts of unrelated conjectures.

 

You bet, I will post as detailed of a video as possible when I get a chance tomorrow.

 

I am following this as I am in the midst of changing my idler, tensioner and alternator. Good info in here and good luck cody, looking ofrward ot you rvideo.

 

You realize this post is a year old?

 

Dang it! I read this thread hoping he found his answer only to get to the end to find out it's over a year old.