I have a 1990 Camaro RS 305 TBI and lately I have been hearing a rattling noise coming from up front. Close to where the alternator is. I'm not sure what it is. I have a video to show you that you can kinda hear it. I think its getting worse and I want to do something about it before something happens.

 

Remove the drive belt & spin & wiggle each accesory, look for loose pulleys, make sure the harmonic balancer is not sliding off the hub.

 

Im kinda new to this stuff. What exactly is the harmonic balancer? Thank you!

 

The balancer is behind the main drive pulley. The 1st pic shows it has walked way off center, looks like towards the rear.

 

I showed my uncle who works on cars and him and my cousin both said the bearing in my water pump is gone. So im gonna replace my water pump and belt and see what happens from there. Thanks for the help.

 

Get that pump replaced?

 

@ ZWis212: I hope that fixed your problem bro but if it didn't ya may want your uncle to change out your timing chain! I have a '91 RS with a 305 and I too had a lot of rattling coming from the front of my engine. Even though it didn't have but 125K miles on it it turned out it was my timing chain! I haven't had any issues after replacing the chain. I did do some other preventive maintenance while I had everything taken apart though

 

Not to hijack the thread, as I have a rattle too. Not as bad as that one though. How do you go about replacing the timing chain? I feel like that is the last rattle I have under the hood at least.

To the OP, did you figure it out? I had a sound like that once, and my alternator froze up shortly after it started. I had to be towed. I don't know how long the sound has happened, but i think I agree with the water pump too.

 

@ Chevydrvr: You'll have to unplug your negative to your battery (so you don't get zapped , (not sure if ya have to really but I removed my alternator to give me more room to work), ya do have to take off your radiator cover (the fan is attached so unplug the plug before removing completely if it's an electric fan), remove the serpentine belt, water pump, harmonic balancer, then take off your timing chain cover (this is a BITCH and if ya mess it up you could have to replace the gasket around your oil pan!). I think I covered it all lol. I replaced my water pump in the process so I wouldn't have problems with it later on down the road. I also took off my intake and valve covers so I could clean everything up. She's still running like a top after all of this and as quit as a church mouse!

 

Oh yea, to remove the balancer you'll have to remove the main drive pulley. I knew I was forgetting something lol. Good luck bro

 

Sorry to jack your thread also, but mine is making noise just like that. Started about a month ago and just got worse. So Z was it the timing chain or water pump? I know i will replace both at same time but just curious. Oh does anyone know if the 2.8 motor has belt or chain???? And what is best part to buy for chain and pump??/Thanks guys

 

bump, whats the best brand for pump and chain, or does it matter?

 

i had a rattle like that, mine was the Smog pump bearing though, hope everyone fixes theirs

 

Sorry for the wait. Yes I did replace my water pump and that was exactly what it was. No more noise at all. Thanka for all the help. We didn't touch anything with the timing and it worked.

 

Thanks for the reply with the "fix".Sooo many questions get asked on here then you never hear from them again.

 

I threw in the timing chain part cause that's what was wrong with mine. Some how with only 115 K miles it stretched.

 

@ Ronusmc: You in the Marine core bro? I have another rattling sound. I'm thinking it's because I advanced my timing to much . I have a '91 RS with a 305 and the sound is coming from the throttle body. I wouldn't have figured the throttle body would have started rattling because of the timing being advanced to much but it wasn't making that sound till I did that. This is my first TBI Camaro, all the others we're carbed. Thanx bro

 

Bumping this thread because of this issue -- can I go about replacing the bearing in the smog pump without buying a completely new one? Suffering from the same rattle and this is the culprit. Thanks!

 

 

You can install new bearings in the AIR pump but its kind of a pain to do.

 

 

Copy that except I'm trying to make this street legal in California! I'm going to take out the pump and see what a bearing replacement looks like -- if it's too much of a pain, it's looking like I should be able to get a good deal on a whole pump considering nobody wants theirs!

Thanks all for the replies -- P

 

Ahh.. California still breaks stones over classic cars? That stinks..

I thought Mass was strict but I always passed with my 87 with no cat or pump hooked up.

 

You bring up a really good point! I should look up if the exemptions start at 25 years or 30 years... Thanks!

 

Just checked.. it’s 1975 and older.. that’s tough.. geez