FAQ: Supercharger Noise (Bad Coupler)

well heres the update:
took both belts off and checked the pullies. alternator/water pump/idlers/ A/C all spun freely. accessory tensioner didnt spin very freely. p/s pulley spun freely but when i wiggled it it had the slightest bit of play. HB didnt budge.
now heres the hard part...
i started it with both belts off and the noise was still there, quieter, but still there. the only thing spinning at this point is the HB, the s/c pulley was spinning VERY slowly. i dont understand what else could be making this noise.
the PO had work done to the engine, from what i know it was tore down to the block and gone through. new water pump, bored to some amount, new springs, and some more things i cant remember right now, ill have to look at the receipt closer and see what you guys think.
another question i have since the engine was apart, is could a loose rocker make a sound at low RPM and then go away when its revved? the reason i ask is what if the shop didnt crank the engine to torque the rockers?
what about main/rod bearings, what do those sound like when theyre bad? IIRC they were replaced by the shop that did everything else. another thing is i seem to remember it saying "balancer polish" on the receipt, if it was polished wrong and the balance shaft is essentially out of balance, would that make a noise like this?

thanks for all the help guys, im starting to get frustrated im stumped. im about ready to just throw and engine at it so i dont have to wonder anymore or worry that something else will go wrong because whoever touched this engine obviously doesnt know what theyre doing.

If the noise is still there without the belts, stick a bomb in it.....

Abaddon wrote:

If the noise is still there without the belts, stick a bomb in it.....

lol i thought about it, couldnt it still be the HB though? i really want to figure this out, i promised her id put an engine in it if it needs it (this was when i was sure it was the HB)

timing chain tensioner? timing chain? idk im just throwing thoughts out, this is driving me crazy. it doesnt help that it also isnt my car and i cant be constantly checking things or tearing it apart, she needs it for work.

I wish i could find the video i posted of my bad balancer, but it sounds exactly the same as your video. With mine the internal shaft cracked causing the pulley to rock back and fourth on the crank. when i pulley the crank bolt out the balancer just fell off

Mr.Riviera wrote:

I wish i could find the video i posted of my bad balancer, but it sounds exactly the same as your video. With mine the internal shaft cracked causing the pulley to rock back and fourth on the crank. when i pulley the crank bolt out the balancer just fell off

do you remember if you tried turning it when the bolt was still on? was it loose before you took the bolt out and did the noise go away with higher RPMs?
with all of the things i keep getting told here and on other forums, the balancer keeps coming up. i think im just going to buy a crank bolt and throw the balancer i already have in and see what it does.

97 park ave wrote:

well heres the update:
took both belts off and checked the pullies. alternator/water pump/idlers/ A/C all spun freely. accessory tensioner didnt spin very freely. p/s pulley spun freely but when i wiggled it it had the slightest bit of play. HB didnt budge.
now heres the hard part...
i started it with both belts off and the noise was still there, quieter, but still there. the only thing spinning at this point is the HB, the s/c pulley was spinning VERY slowly. i dont understand what else could be making this noise.
the PO had work done to the engine, from what i know it was tore down to the block and gone through. new water pump, bored to some amount, new springs, and some more things i cant remember right now, ill have to look at the receipt closer and see what you guys think.
another question i have since the engine was apart, is could a loose rocker make a sound at low RPM and then go away when its revved? the reason i ask is what if the shop didnt crank the engine to torque the rockers?
what about main/rod bearings, what do those sound like when theyre bad? IIRC they were replaced by the shop that did everything else. another thing is i seem to remember it saying "balancer polish" on the receipt, if it was polished wrong and the balance shaft is essentially out of balance, would that make a noise like this?

thanks for all the help guys, im starting to get frustrated im stumped. im about ready to just throw and engine at it so i dont have to wonder anymore or worry that something else will go wrong because whoever touched this engine obviously doesnt know what theyre doing.

We are taught to go to back to the place last worked on to find the problem.
If you are going to follow that path then you need to convince yourself that it is worth taking this motor apart until you do find the problem.
If this is the path you chose then Good Luck to you. After swapping the HB's and if that's not it, then you need to start from the top down, in my opinion and remove the SC and LIM to get a look at the valley and the Balancer shaft to see if that is installed correctly, or in one piece, as well as removing the Timing Chain Cover to check the chain, gears and tensioner.
Then if that isn't the problem............................................................

You know what I'm getting at. If you have the opportunity to return this car, you may want to give serious thought to doing that at some point in the process. Preferably before the deadline.

There are too many vehicles for sale, for reasonable money, to be messing around with someone else's problems. This guy must think he found the sucker of all suckers to take this car off of him. The car he has spent so much money on to get it right, and it still makes BAD engine noises.
Just my suggestion, Back away from this deal and get your money back, if at all possible.

can you pull the passenger wheel and take a picture of the front of the balancer for us?

Quote:i started it with both belts off and the noise was still there, quieter, but still there. the only thing spinning at this point is the HB, the s/c pulley was spinning VERY slowly. i dont understand what else could be making this noise. Quote.

The only thing at this point are all the things you cannot see with the motor running. Start thinking about the fact that the timing chain, gears and tensioner are still working along with every OTHER rotating component in the engine.

You don't know the quality of the work already accomplished or if any of it was accomplished. Sorry.

Rickw wrote:

97 park ave wrote:

well heres the update:
took both belts off and checked the pullies. alternator/water pump/idlers/ A/C all spun freely. accessory tensioner didnt spin very freely. p/s pulley spun freely but when i wiggled it it had the slightest bit of play. HB didnt budge.
now heres the hard part...
i started it with both belts off and the noise was still there, quieter, but still there. the only thing spinning at this point is the HB, the s/c pulley was spinning VERY slowly. i dont understand what else could be making this noise.
the PO had work done to the engine, from what i know it was tore down to the block and gone through. new water pump, bored to some amount, new springs, and some more things i cant remember right now, ill have to look at the receipt closer and see what you guys think.
another question i have since the engine was apart, is could a loose rocker make a sound at low RPM and then go away when its revved? the reason i ask is what if the shop didnt crank the engine to torque the rockers?
what about main/rod bearings, what do those sound like when theyre bad? IIRC they were replaced by the shop that did everything else. another thing is i seem to remember it saying "balancer polish" on the receipt, if it was polished wrong and the balance shaft is essentially out of balance, would that make a noise like this?

thanks for all the help guys, im starting to get frustrated im stumped. im about ready to just throw and engine at it so i dont have to wonder anymore or worry that something else will go wrong because whoever touched this engine obviously doesnt know what theyre doing.

We are taught to go to back to the place last worked on to find the problem.
If you are going to follow that path then you need to convince yourself that it is worth taking this motor apart until you do find the problem.
If this is the path you chose then Good Luck to you. After swapping the HB's and if that's not it, then you need to start from the top down, in my opinion and remove the SC and LIM to get a look at the valley and the Torque shaft to see if that is installed correctly as well as removing the Timing Chain Cover to check the chain, gears and tensioner.
Then if that isn't the problem............................................................

You know what I'm getting at. If you have the opportunity to return this car, you may want to give serious thought to doing that at some point in the process. Preferably before the deadline.

There are too many vehicles for sale, for reasonable money, to be messing around with someone else's problems. This guy must think he found the sucker of all suckers to take this car off of him. The car he has spent so much money on to get it right, and it still makes BAD engine noises.
Just my suggestion, Back away from this deal and get your money back, if at all possible.

i have no problem working on it, i have even told her to bring it back and we'll look more but she wants this one. i know the guy since hes always at my work and he knows i know 3800s so im guessing he thought it would be easy for me to figure out. im all for bringing it back, but if its just the balancer then i dont want to if i can fix it. the way i look at it is worst case i have to put an engine in it. ill only be out somewhere around $600 and itll keep the girlfriend happy, im sure you all know where im coming from lol.

Mr.Riviera wrote:

can you pull the passenger wheel and take a picture of the front of the balancer for us?

depending on how tired i am when she gets home i might look at it tonight, otherwise itll have to wait til tomorrow. either way ill get a picture from the front of the balancer. what would a picture from that point of view tell you if you dont mind me asking? and do you want the picture with the belts on or off?

Rickw wrote:

Quote:i started it with both belts off and the noise was still there, quieter, but still there. the only thing spinning at this point is the HB, the s/c pulley was spinning VERY slowly. i dont understand what else could be making this noise. Quote.

The only thing at this point are all the things you cannot see with the motor running. Start thinking about the fact that the timing chain, gears and tensioner are still working along with every OTHER rotating component in the engine.

You don't know the quality of the work already accomplished or if any of it was accomplished. Sorry.

i was thinking about the timing chain tensioner too, what i was also thinking though, is the HB is still spinning even with all of the belts off. i think i might throw a balancer at it, i have one in the garage and crank bolts are $20 max right?

When mine cracked the rubber around the pulley was visually tearing. belt on or off doesnt matter.
You could try to get a pic with the wheel on the car but w-bodys dont have much room on the passenger side with the coolant reservoir.

Crank bolts are like $8 from zzp, but i reused mine with threadlocker. You could always pull the bolt later and replace it with a new TTY bolt.

edit: $10...

So, are you saying you are stuck with this car. Period.

I thought you said you had a way out before Thursday.????

Mr.Riviera wrote:

When mine cracked the rubber around the pulley was visually tearing. belt on or off doesnt matter.
You could try to get a pic with the wheel on the car but w-bodys dont have much room on the passenger side with the coolant reservoir.

Crank bolts are like $8 from zzp, but i reused mine with threadlocker. You could always pull the bolt later and replace it with a new TTY bolt.

edit: $10...

i dont have time to wait for ZZP, how much vaseline should i bring to the dealer? i think you missed my other question, do you remember if you could move the pulley back and forth before you removed the crank bolt.

Rickw wrote:

So, are you saying you are stuck with this car. Period.

I thought you said you a way out before Thursday.????

technically the car is still his, she still has to give him $300 and he has to give the title. this is supposed to happen thursday. i was trying to figure out exactly what it was so i could weigh my options to decide whether or not to tell her to bring it back or not. i already told her she could, she still wants it. hopefully if i find its internal she wont want it, but also on the other hand i hope not cause then i get to deal with an unhappy woman.....not fun. i really hope its just the balancer, i think ill put one in tomorrow after i snap pics for mr.riviera.

I can not remember being able to move the crank much. are you able to spin it with your hands?!? i have to put a ratchet on it to get it past TDC unless the plugs are out.

Mr.Riviera wrote:

I can not remember being able to move the crank much. are you able to spin it with your hands?!? i have to put a ratchet on it to get it past TDC unless the plugs are out.

no thats the thing, everyone is saying i should be able to move it with my hands with the belt off if its bad, it didnt move at all. like i said though, i already have a spare balancer so all i would need is a crank bolt, i think im going to take the chance.

well, it was NOT the harmonic balancer. i replaced it and it seemed a bit better at first but i gave it a rev and it made the same noise. the old balancer had a bit of play anyway so im not too pissed, but i do think i know what it is now. im back to the supercharger, i think its either the gears or the rotors themselves and possibly even the coupler. i can turn the pulley back and forth with the belt off and it makes one noise, but with the belt on i discovered a completely different noise, a noise that sounds like when the car is idling.
here are the pics of the balancer before i took it off mr. riviera:



and here is the video of the sound:
https://www.youtube.com/watch?v=0f7S_XipwXM

Looks like you eliminated one possibility, Based on the video, it sounds like the supercharger, hopefully your assumptions are correct when you open up her up. Good luck, man.

Sorry to hear it was not the balancer. At least you had one handy and it ruled it out. I would not have diagnosed it bad based on that picture above though. (too late now though)

If you need a spare gen 3 let me know. i still have one for sale.
Its P&P with N* adapt, 3.4 and painted gloss black, but i can remove the pulley and N* adapter if you want.

Mr.Riviera wrote:

Sorry to hear it was not the balancer. At least you had one handy and it ruled it out. I would not have diagnosed it bad based on that picture above though. (too late now though)

If you need a spare gen 3 let me know. i still have one for sale.
Its P&P with N* adapt, 3.4 and painted gloss black, but i can remove the pulley and N* adapter if you want.

how much for it without the N* adapter and 3.4?

pm on its way

Tyler, based on your video, I'd say it is the snout bearings... You've run the engine before with the blower belt off, try doing it again, and try holding/releasing the blower pulley with your left hand while gunning the engine with your right hand, and see if you can isolate it. Your may well just need a new snout.

Eldo wrote:

Tyler, based on your video, I'd say it is the snout bearings... You've run the engine before with the blower belt off, try doing it again, and try holding/releasing the blower pulley with your left hand while gunning the engine with your right hand, and see if you can isolate it. Your may well just need a new snout.

i was thinking about the bearings too, i know its definitely in the snout. when i listen with a screwdriver, there is a bit of noise coming from the snout right by the pulley, but there is a lot of noise coming from the base of the snout where the gears are.
ive tried holding the pulley while giving it a rev, the noise is still there. thats the main thing that has been confusing me about this noise, even with the belt off the noise is there but there is absolutely nothing else that could be turning just from the supercharger pulley turning because im just using the slack of the belt to turn it. the s/c idler and tensioner are new, and the HB wont budge just by pulling on the belt.
at this point im either going to throw one of the 2 blowers i have on right now, or buy mr. rivieras from him.

If after you do the mentioned exercise with the SC and still have the noise, consider that it may be coming from down a little deeper in the Timing Chain case.

Just a thought and a spot to put your stethoscope when you run the engine with no belts on it. Just try to hear what's coming from that area too. I'm curious to know if the timing chain and a worn tensioner could make that kind of noise.

Thanks,
Rick

Rickw wrote:

If after you do the mentioned exercise with the SC and still have the noise, consider that it may be coming from down a little deeper in the Timing Chain case.

Just a thought and a spot to put your stethoscope when you run the engine with no belts on it. Just try to hear what's coming from that area too. I'm curious to know if the timing chain and a worn tensioner could make that kind of noise.

Thanks,
Rick

thats what i was possibly thinking, but how would the timing chain be moving from just the supercharger pulley moving?