I just started my bonny and let it warm up approx. 7 minutes...put it in reverse to back out of garage and heard a rattle something like a Catalytic rattle but coming from under the hood....popped the hood and from what i can tell it is the sc but the rattle stops when i give it some gas ..and then rattles again when idling....I was preparing to change the sc oil tomorrow...should I bother now?? Do I need a new SC? ....any help will be greatly appreciated...thank you

The rattle could be a tranny mount or an engine mount based off what you wrote. I would check those, rule them out and then move on to other things.

I just went out and started her up again....the rattle is like a plastic baseball card in the spokes sound and is definately coming from the SC but when i give it gas it stops...wierd, it'* tough to pinpoint the sound but i think it is originating in the pulley end....does anybody know what a new sc will cost or a possible upgrade...if I am replacing it anyway?

itis understandable that once a load is on it that it is quiet if it'* the SC coupler.

The way the coupler works is three pins from the nosedrive shaft go into the coupler and three other pins from the rotor pack gear go into another three holes in the coupler. The coupler is a hard plastic that takes up the place of shock and things like that.

Here is a coupler on the gear side. Coupler is green


And this is the nose drive side. We can see how they go together


The holes egg out over time and miles. While your noise is common, it'* not a threat to the motor. A coupler swap in a 92-95 requires the charger to be removed from the motor. As long as you are going that far, I'd pull the LIM and replace the gaskets as well.

Most posts you see on this forum will say that the S1 motor doesn't suffer from the gasket issue, but having seen a few in person..they do. Once in a while there will be an exception to the rule, but most are in need of being replaced.

Here'* a write up on changing the coupler.

https://www.gmforum.com/t279064/

Thanks alot you guys rock!!...Looks like i have a bit of a project ahead of me for the weekend...just one more question...i have my grandmothers funeral this friday and it is about 1.5 hours away would it be safe to drive or should i consider renting a car....Thanks again for the info it was above and beyond my expectations....Jason

Id say it should be okay to drive (not taking the blame if something goes ary)... just consider replacing some time soon, not that expensive all in all but if you do have to pull the supercharger be sure to set aside the whole day unless youve done it before... itll take several hours to remove and replace the sc and more if you plan to replace the lim gaskets while your at it... which is also something to really look into, youll be halfway there already, go the distance so you dont have to later

btw my father, shade tree mechanic, took 9 hrs to replace the charger with hand tools... would take less with air tools but depends on what you have and how often you do it lol

I drove my 92' until it was so loud I couldn't here my radio anymore--sounded like a train. I got a coupler for like $15 and replaced it with out taking the SC off--like an hour and a half, made all the difference. It was then that I noticed the oil plug, I had been driving it with no oil for a WHILE!! If yours is emty put a new front seal in it to.

anybody know the reason why the m62s have to be removed to change the coupler? mine has bolts all the way around, one would think it would just pull apart with them undone... i could be wrong tho.. never done it

To my knowledge you do not need to remove the whole charger to change a coupler. Keep in mind many dealerships still remove the charger to drain the snout oil. That way they can turn it upside down. There is a hidden bolt behind the snout.


Make sure you pull that one as well.

Suck out the snout oil before you take it apart.