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plstktnkr2
08-19-2009, 08:38 PM
is there supposed to be ANY play between the pulley and shaft of the blower jackshaft?

DrFishbone
08-19-2009, 09:03 PM
There shouldn't be if the bolts are in and tightened down. :confused: If the bolts are removed and the pulley spins on the shaft, that is okay. It's not a press-fit...if that's what you're wondering.

plstktnkr2
08-19-2009, 09:11 PM
with everything in its place, there is rotational play , guess I have to take it apart and see whats up

the-big-e
08-19-2009, 09:39 PM
You most likely have a spring loaded coupler....

Does the pulley "click" when you rotate the pulley back and forth or does it get kind of firm, then spring back......

plstktnkr2
08-19-2009, 09:42 PM
no does not click , its like a work keyway on a shaft

Mike8675309
08-19-2009, 10:51 PM
is there supposed to be ANY play between the pulley and shaft of the blower jackshaft?

You're talking about the jackshaft right? Not the actual blower. The shaft that the jackshaft pulley bolts to is supported by two bearings pressed into a bore in the accessory bracket. There should be near zero movement perpendicular to the pulley. tolerance is like a front wheel bearing. The bearings are not user serviceable.

plstktnkr2
08-20-2009, 09:24 AM
You're talking about the jackshaft right? Not the actual blower. The shaft that the jackshaft pulley bolts to is supported by two bearings pressed into a bore in the accessory bracket. There should be near zero movement perpendicular to the pulley. tolerance is like a front wheel bearing. The bearings are not user serviceable.

Blower(not jackshaft) has pulley on the end. the nut is tight, but pulley is loose. turns a bit on the shaft when all parts held still, like it has a bad key or something

Mike8675309
08-20-2009, 11:22 AM
Blower(not jackshaft) has pulley on the end. the nut is tight, but pulley is loose. turns a bit on the shaft when all parts held still, like it has a bad key or something

The blower pulley is a interference fit with a keyed shaft to back it up. If the pulley is loose, either the shaft on the blower is worn, or the pulley itself is worn. Any issue with the key is secondary, as there should be no movement, even if you didn't have a key inserted in the keyway. Assuming you are talking about the stock M90 blower used in the SC cars.

David Neibert
08-20-2009, 01:10 PM
You are probably feeling the slack between the supercharger input shaft and the rotor pack input shaft, because of wear/slack in the coupler.

David

DrFishbone
08-20-2009, 01:36 PM
Yeah, the blower pulley indeed should not rotate when installed, even with the nut and keyway removed. Do you have an aftermarket pulley on there or something? Maybe if the keyway was left off and the fit wasn't very tight (like my 5% aluminum pulley), it broke loose and started to slip on the shaft. Now, however many miles/years later, it can be rotated by hand. Like Ed (the big e) said though, some sc's have a "spring coupler" that make the sc feel like it has play, but if the end of the shaft/nut and pulley are rotating independently...something is wrong.

plstktnkr2
08-20-2009, 03:59 PM
shaft-nut and pulley are rotating independently
ok something is amiss

90MN12
08-20-2009, 06:01 PM
sounds like rebuild time.

the-big-e
08-20-2009, 06:13 PM
Sounds like there is no key in the key way of the shaft.....:eek:

plstktnkr2
08-20-2009, 09:44 PM
Sounds like there is no key in the key way of the shaft.....:eek:

my theory exactly see post 7
thankx everybody :)

Mike8675309
08-20-2009, 10:19 PM
my theory exactly see post 7
thankx everybody :)

Again. the key is there to assist in locking the pulley on the shaft. But that won't be strong enough on it's own. There needs to be a friction fit on the pulley to the shaft.

plstktnkr2
08-20-2009, 10:36 PM
yes I understand that thanks, sort of a press-fit ,with key, plus nut .