'92 Bonny SSEi
155K miles

Started her up yesterday afternoon... (and fortunately I was parked in my own driveway!). Heard very loud rattle/grinding noise coming from the engine. Scared out of my wits, I shut her down immediately, changed my shorts and tried again a few minutes later. Same loud noise occured again. Opened the hood and listened for a second with the engine running.... Sound seemed to be coming from the belt/pulley/SC area of the engine. Placed my hand on a few different areas of the engine (still cool yet as I just started her up) but couldn't feel any real vibrations from any specific area. Pulled her into the garage and shut her down again. Jumped in the alternative vehicle (we won't go there...) and took off to my 'appointment'.

This morning I tried again, same loud noise from the same area. Shut her down and pulled off the outside belt (Alt./PS/etc.). Started her up... same noise. Shut her down and pulled the inside belt (SC/AC/WP/etc.). Started her up... noise went away.

(The following is para-phrased from another post I found while doing a search... it seemed to describe my problem) ** Found that with the belt off you can rotate the pulley on the SC shaft about 1/8 " before it seems to connect inside. If you rotate it back and forth quickly you can duplicate the rattling sound. It is not loose in any other direction and does not leak. **

Inside belt pulleys and the Water Pump are new... less than 500 miles. AC compressor new within about 5K miles. New belt was repleced with the WP ordeal. Only thing not touched is the SC... other than to flush and fill the SC oil about 15K miles ago.

So I'm thinking it'* the SC, correct?
Do I need a new SC or can I rebuild this one?
How do I know if I have a M62 vs M90, Series I vs Series II, Magnuson vs Eaton, anything else?
Doesn't look like too bad of a job to R&R.

Thanks guys... Ace

you need a new coupler...$30 part, just a time consuming job

Does it rattle only at idle?

What part of the Twin Cities are you from? I have had this problem before and was able to diagnose and fix it. I'd be glad to help out if I can.

Sounds like a coupler to me, but I'm by no means a very knowledgable person about these cars.....But kinda sounds like what I got goin on with my ride. What happens if these couplers get completly shot????

If they go out completely you will have no boost and your car will become pretty much undriveable. I know mine had been making noise for about 2.5 years before I finaly knew what it was and fixed it. Mine also had a lot of wear on it then and was close to failing completely. In most cases it will take time to wear it out to the point of failure, but that doesn't meant that it can fail quickly either.

Series 1, M62. Used in 92/93, similar used in 94/95. Very likely the coupler. Remove the inner belt and move it by hand. Procedures are all over the Forced Induction forum. Moving this there now.

Rattles all the time.
I'm in Apple Valley and would be happy to take any help offered. Let me know!

Thanks in advance, Ace

If you are willing to drive it up to Crystal (after 4pm) any day of the week I will be happy to check it out for you. IF it turns out to be the coupler (which I suspect it is) I'm sure a few of us here in MN would be willing to help you change it out some long Saturday afternoon.

If you can give me enough warning i can take a weekend off of work, My parents live in lakeville i can come up and help out

Otherwise i'll be in town oct 22-24 for sure.