Topend chatter supercharger maybe...?

**TorqueAutoMotiv** · 04-26-2009

So last night i bought a 98 gtp ive been looking for about 3 weeks and the one i found has high miles 150k+

well theres a slight chatter from the supercharger i can feel it in the nose peice.

now my ? is this what is the most likely cause of the this and how should i go about diagnosing and repair

Im new to the gtp world but not cars so i can do the work myself..

Thanks for any input of help

**Bio248** · 04-26-2009

if you feel it in the snout it is probably a coupler or the snout bearings. most likely it is the coupler. does it sound like tumbling rocks?

**TorqueAutoMotiv** · 04-26-2009

yea i can feel it on the snout and when the car shuts off it kind of rattle/grinds like rocks in a tumbler

is the coupler or bearing a easy or harder thing to fix and will i need special tools

**Bio248** · 04-26-2009

coupler is easy, you just have to take the blower apart. it connects the rotors to the snout shaft. just a circular piece of plastic with holes in it.

bearings youll need a press. i wouldnt do them on your own unless you have a press..

**TorqueAutoMotiv** · 04-26-2009

Im in auto tech classes right now and have about 500grand in tools at my disposal so the press isnt a problem
Ive never puulled apart a charger before is it pretty straight forward
and will i need to pull the pulley off to take it apart

**Bio248** · 04-26-2009

really easy. yes, youll have to pull the pulley off, but then again, ive never taken any of the bearings out. i just buy a different snout/rotors/case instead since it costs about the same amount for me.

**minichopper6hp** · 04-26-2009

there is a write up here M90 Supercharger Disassembly

**TorqueAutoMotiv** · 04-27-2009

thanks for the link helps alot looks pretty basic

**Zbones** · 05-07-2009

I have the same problem on my 98 GTP. Just to clarify though, you HAVE to remove the pulley from the charger in order to simply open it and replace the coupler, or can it be left on? Only reason I ask is if the pulley needs to come off that means most likely investing in a pulley puller just to switch out a little coupler. Thanks for the help.

**Sabrewings** · 05-07-2009

The pulley stays on. You just have to slide the snout off.

**Bio248** · 05-07-2009

the snout separates from the rotor pack which separates from the blower case.

just a few bolts around the snout and then pull it apart.

**blueguy** · 05-07-2009

A few long bolts...and if you are just replacing the coupler you only have to pull the snout off but be sure to drain the supercharger oil first...there is a small black piece in the front of the snout that can be removed with a alan wrench. Siphon the old S/C oil out (be sure to have 2 bottles of new S/C oil which you can get from a dealership) and remove the oil coupler and put the new one on. Best couplers IMO are the green ones from ZZ Performance.