I believe I have a bent SC shaft

[crush]

I was replacing the belt today and turned the SC pulley to see how every thing moved. It seemed to be stiff to me but IDK. What concerns me most is the gap between the SC pull SC nose changes. The most noticeable differences are that every 180 degrees or half turn(1 8th of an inch). what problems will this cause(other than eating up belts). Also if the SC needs to be replaced can I upgrade to a gen3 or 5.My Bonnie is a 92 SSEi.

[clm2112]

More likely the pulley is bent, not the shaft.

Easy way to tell, take a chunk of coat hanger wire and make a pointer out of it. Attach it to the motor with one of the accessory bracket bolts and bend the free end so it almost touches the tip the the SC shaft where it peeks out the center of the pulley.

Now rotate the SC by hand and watch the gap between the tip of the coat hanger and the actual shaft the pulley rides on. If the gap changes, the shaft is bent. (Correct method for measuring run-out is to use a dial gauge the same way, but for a quick "Yep, It's Bent" test, a simple wire pointer will do.)

You can repeat the same test on the edge of the pulley (actually, one of the belt ribs is a better reference point..it's usually better machined than the actual edge of the pulley.) If the shaft is OK and the pulley wobbles relative to the pointer, then the pulley got bent. If both are OK, then it's just an optical illusion.

I'll let the others comment on the swap possibilities. If the shaft is bent, then you can just have the nose of the supercharger rebuilt.

[crush]

THANKS, I,ll pull out my dial gage in the morning and check the shaft itself while I wait for the others opinions on the swap over.

[willwren]

If the gap between the pulley and the nosedrive changes, you have a bad bearing or two. Running long-term like this COULD cause the loss (damage) of your nosedrive.

Without knowing for sure what it looks like in there, I think a new (used) nosedrive may be in order. Replace the bearings in it before installing with a new coupler.

[willwren]

Here's some more info:

http://www.3800supercharger.net/diagnosing.html

[crush]

put the dial gage to the shaft and no movement, put it on the pulley and it moved between a 16th to 8th inch in at least 3 spots. still like to know about SC upgrade.

[willwren]

You can't afford to adapt a GenV, and you don't want the headache of a Gen3. Trust me, the only Gen3 swapped cars (2 of them) on this Forum STILL fight for a good tune daily.

Repair your issue with the Gen2. I have a very hard time believing you bent a pulley. They're steel. You are very likely seeing the effects of failed bearings. It will be more pronounced with the dial indicator simply because it's farther from the 'pivot' point or the outer bearing.

[crush]

Were would be a good place to find my nosedrive or a rebiuld kit. I still think I may change pulleys just for good measure, but could I use a quick change kit for when I am finally ready for a smaller pulley?

[willwren]

There is no quick-change system for the Series 1, nor do you need one. You have a keyed shaft, not tapered.

Look at my supercharger page I linked above. Click on LINKS, but remove the extra www (I have a bad hyperlink there):

http://www.3800supercharger.net/links.html

RollingPerformance is listed there. You can get the bearings, oil, and sealant all from one source. You MUST have a press to disassemble and reassemble the nosedrive. Or you can get a rebuild from canadiansupercharger (listed there) or simply get a spare from the wrecker or ebay. I strongly suggest rebuilding a wrecker or ebay supercharger or nosedrive before use.