10% pulley and pulley key

Dono

Registered User
Through my own stupidity trying to get my pulley to line up better with my M90 (My mount is for a ford explorer) , I shimmed my pulley out, and obviously the washer method is all bad. I trashed my 10% pulley and the shaft key.

Hope you guys don't mind an explorer guy hanging out around here. At least its a Ford though.
 
Check out super coupe performance. They have the three jaw pullers and you can get another pulley also. I trashed two pulleys myself trying to put an underdrive pulley on my brother in laws car. The first one was practice:rolleyes:
 
Thanks!. Ive been able to remove and install the pulleys without the puller. That's a good thing.
I am concerned about the key that slides in to the shaft and slot of the pulley. Mines pretty chewed up now.

Your right, I have to suck this one up as a learning experience. Too bad. The pulley was a nice aluminum one. Maybe I'm better to go steel this time.
 
Thanks!. Ive been able to remove and install the pulleys without the puller. That's a good thing.
I am concerned about the key that slides in to the shaft and slot of the pulley. Mines pretty chewed up now.

Your right, I have to suck this one up as a learning experience. Too bad. The pulley was a nice aluminum one. Maybe I'm better to go steel this time.

You might want to check the hardware store for the Woodruff key. I think it's a standard size. If it is metric, you could file down a standard one.

There is a nice cheap steel 10% pulley out there. I think it's from March performance. Summit Racing used to have it in the catalog. There is probably one for sale here used, too.
 
Jludorf has a pulley for me (steel).

I bought the last one from him (Aluminum).

I'd obviously prefer aluminum, but I am not sure it will stand up to the forces, with it being shimmed out. I did learn my lesson not to shim out so far though. If my belts a bit off, it wont be a big deal.

Once I get my tuning sorted out with the 10% pulley, I'll post my HP/Torque numbers after a trip to the dyno. I'm interested in what a poor old push rod 4 liter motor in an explorer can do. You guys might be amused also.

You guys are great. Thanks.
 
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Jludorf has a pulley for me (steel).

I bought the last one from him (Aluminum).

I'd obviously prefer aluminum, but I am not sure it will stand up to the forces, with it being shimmed out. I did learn my lesson not to shim out so far though. If my belts a bit off, it wont be a big deal.

Once I get my tuning sorted out with the 10% pulley, I'll post my HP/Torque numbers after a trip to the dyno. I'm interested in what a poor old push rod 4 liter motor in an explorer can do. You guys might be amused also.

You guys are great. Thanks.

You're still going to try shimming it? I don't really recommend that, since the shaft and pulley have a tapered fit. The woodruff key is really not designed to take the force of turning the blower (up to 100 HP!).

If you really needed to shim it, you would need a cone machined at the exact same angle as the shaft's taper. The better thing to do would be to move the entire blower forward. Or, if you only need a very small amount of movement forward, you could make a spacer out of thick aluminum sheet stock and cut it to match the sealing surface between the blower snout and the rotor pack. The pins on the shaft drive should be able to tolerate a little less engagement into the coupler. Maybe up to .1 inch?
 
Im almost thinking of pulling the mount, and making the current holes oblong(4, since the SC is actually mounted upside down, with the M90 air exit pushing air into my lower intake manifold).

Then I would be able to slide the M90 forward. 1/4 inch. Im certain that would be enough.

I didn't notice the taper of the shaft. Even using the shims, it has to add a ton more stress on the bearings. Ok, you have convinced me. I won't do the shim thing.

Thanks for chiming in. No point in continuing to do the same thing and wonder why I have the same problems. Better to do it the right way.
 
Im almost thinking of pulling the mount, and making the current holes oblong(4, since the SC is actually mounted upside down, with the M90 air exit pushing air into my lower intake manifold).

Then I would be able to slide the M90 forward. 1/4 inch. Im certain that would be enough.

I didn't notice the taper of the shaft. Even using the shims, it has to add a ton more stress on the bearings. Ok, you have convinced me. I won't do the shim thing.

Thanks for chiming in. No point in continuing to do the same thing and wonder why I have the same problems. Better to do it the right way.

You might want to just double-check, but I am 99% sure it is tapered, even though there is a keyway. I know that the later Eaton blowers, as used on the Lightning truck and the GM passenger cars, did away with the keyway and just used a tight press fit. But I think there is a loose taper fit on these pulleys too.

You read me right, I am just trying to help you avoid future problems.
 
I think you're right Steve. Also, the aluminum pulleys don't have as much of an interference fit - at least the ones I've used.
 
I think you're right Steve. Also, the aluminum pulleys don't have as much of an interference fit - at least the ones I've used.

Thanks, Matt.

I think I have one in storage with the pulley off. I will check it if I get out there soon.
 
Yes, tapered shaft.

I just tried reversing a pulley to see if it would slide on, it won't properly.

Thanks guys, that confirms that there is no way there can be shims behind that pulley. The help is appreciated.
 
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