I am wondering if any of you have replaced or at least removed and inspected your superchargers nose drive....

Mine was making some aweful growling and grinding and getting real nice and hot. So i finally pulled it off the car to send it in for a rebuild.
so i figured before i send it in, i might as well crack it open and take a look and see how bad things really are... so i feel better about dropping all this money on a rebuild.

according to all i read... the VAST majority of SC wear and growling is causes by a worn plastic coupler. sometimes the damage can go as far as the nose drive bearings. and in rare cases, the actual rotor pack bearings can go too.
I heard that bad nose drives can lead to dark almost black oil, and some metal shavings floating about.

Well as loud as mine was... i expected the coupler to be pulverized, and the oil to be black and full of bearing shavings...

so i pull off the nose drive and find it to be in what appears to be perfect shape. The coupler looks brand new, no ovaling, no cracks, no stretching, no slop at all. It sits real tight on the pins and looks as good of shape as the a new one.
The nose drive shaft feels firm and soild, definately not loose or anything. no noise at all from spinning it, and apart from what i assume to be a litttle pre-load resistance on the bearings, she turns just fine. i held one side and tried to wiggle the other and there was no give at all.

the oil after 100k was lighter than engine oil after a few weeks. far from black... kinda of similar to coffee or root beer in color and transparency (brown/tan when poured, but dark brown when in a clear container. there appeared to be no shavings in the oil untill the very last few drops where i saw a little bit of "sediment" right at the very bottom.

I know the rotors and case are a different story... i can see the wear just looking down the throttlebody. but didnt want to pull the rotor pack from the housing as i heard it is no small chore to get the rotors synched back up properly. but the rotor gears seem perfectly meshed. no play at all between them. no movement laterally at all. seems to be a little play in and out along the shaft... (as if you were trying to pull the gears out and push them back in)

so i guess the things i would like to know from you guys.....

1. (when removed from the SC) should a healthy nose drive have any resistance when you spin it . Should it spin freely like a new roller skate wheel (blowing on it hard will start it spinning)? Very light resistance like the volume knob on a stereo (easily turns with light pressure from your pinky)? Medium resistance like the knobs on an oven or washing machine (requires grasping with pointer finger and thumb to turn, or possible with alot of force from one finger)? High resistance, like finger tightening a bolt, or a opening a jar.. (need a good firm grip and wrist action to open it, fingers are futile)

2. What color / consistency should the SC oil be in a properly maintained and healthy but used SC? clear like water? like iced tea? like root beer? like pepsi? like espresso? thin like liquid? medium like motor oil? thick like warm maple syrup? real thick like cold maple sytup?

3. How much play if any should there be in the rotor gears? in out? up/down/sideways?

4. can the rotor pack be removed from the case without risking damage to the rotors or screwing up the rotor timing? (it seems like it should come out as one unit with both rotors and gears held in place by the removable section of case right behind the nose drive. but just wanted to make sure. before i pull it off and watch as the rotors and bearings all fall on the floor and roll off in different directions.)

I am going to say this as nicely as I can.... Leave it alone, send it to a professional rebuilder like Stiegemeier. I know him personally, and have watched them rebuild/overhaul many units. If you don't know exactly what you are looking for, you will never find an issue. You can also damage the unit if its not put back together correctly. There are alot of tolerances that need to be checked on different components. I am 100% positive you don't know what you are looking for. You also may want to check your idler. The sound can travel and make other things appear to be at fault.



P&P Tuning
420.5whp / 359.8wtq

ImPhat0260/Cavattack2000 wrote:I am going to say this as nicely as I can.... Leave it alone, send it to a professional rebuilder like Stiegemeier. I know him personally, and have watched them rebuild/overhaul many units. If you don't know exactly what you are looking for, you will never find an issue. You can also damage the unit if its not put back together correctly. There are alot of tolerances that need to be checked on different components. I am 100% positive you don't know what you are looking for. You also may want to check your idler. The sound can travel and make other things appear to be at fault.

Well thank you for putting it in such a civilized fashion. I am willing to take you seriously when you put it like this.

This is the sort of thing i was wanting to know.... I almost definately will still send it out for a rebuild....

But still, i wouldnt mind some answers to my questions... just for my own information.

worn couplers cause a rattley noise get the ZZP onei think the M45/62/90 all use the same coupler

while its off replace the bearings i did mine but i also did the case needle ones too mines nice and quiet not



JBO since July 30, 2001

the case bearings are a bitch... and are diffrent then the ones for the m90-m62.. sucks.

rebuilding the snout is easy.

Chris




'02 Z-24 Supercharged
13.7 @102.45 MPH Third Place, 2007 GMSC Bash SOLD AS OF 01MAR08

yeah, i have read up on snout rebuilding. doesnt look so bad at all to do.. just the pressing of the bearings and all....

but i talked to a couple places and they say that they wont even touch the needle bearing in the case... a few places say if they need replaced they just gety a whole new case with bearing installed... cuz they say it is soooo hard to replace those bearings.

so you guys have actually managed to sucessfully replace them yourself? if so how did you do it?

also, chris, you sure the rotor bearings are the different on the m45 than the m62 and m90 etc? i found a set of rotor bearings for the m62. hoped they were the same.

My snout seems 100% a-ok... but i am sure the case bearings are shot.

and what supports the nose-drive-side of the rotors? those have to have bearings or something there too dont they?

ive taken about 3 m62's apart, they are pretty much the same inside, just different size gears, rotors, and @!#$...but if you can do one, u can do the other...istn really hard if its doing a growling noise sounds like the coupler in the sc has gone bad, its a aeasy, 30mins replacement...but you said u already inspected it, the pulley itself wil turn by hand, it will not turn by blowing on it, it will not sping as easy a roller skate, u it should only spin, while ur spinning, when u stop spinning, the pulley should stop spinning...to help pinpoint then npise i recommend this

-thread in a bolt on the main stud by the pulley...
-use a power drill to turn the bolt which will turn the pulley which will turn the rotors
-try and pinpoint where the noise is coming from

there is a video on youtube on how to do this, i believe u can find it by searching "mp62"

My MP45 when brand new would rotate with medium resistance as you described it.


2001 Olds Alero (LD9)
650 whp / 543 ft-lb
@turboalero