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Bleed_Ford_Blue
08-30-2004, 12:43 AM
Hey guys,

I just put on my new underdrives and my tensioner pulley (alternator) is bouncing back and forth wildly. It is moving nearly 4 inches. The pulley is at the very end of its range of motion when at rest so I think a new shorter belt would help. Any idea where i could get one, Ive tried the standard venues to no avail. I got to get this fixed before it strands me, that and it clatters like ive got 7 out of 6 rods knocking. By the way, I replaced both the tensioner and pulley so that isnt the problem.
Please help
Dan

cougarsc
08-30-2004, 01:05 AM
On 94-95 SC's, you need a spacer for the underdrive on the alternater. See if it spines freely with the belt off.

pearl95sc
08-30-2004, 01:05 AM
Go to pep boys. They have all the belts on display and you should be able to compare your stock belt to a shorter , similair one.

Bleed_Ford_Blue
08-30-2004, 08:43 AM
it spins freely, it has the spacer on it. I am nearly stumped.

David Neibert
08-30-2004, 08:51 AM
If you install all three pulleys, the belt length doesn't change....you did install all three didn't you ?

David

Bleed_Ford_Blue
08-30-2004, 09:03 AM
Yes, I installed all three pullies, I even changed belts to see if the first one stretched

Bleed_Ford_Blue
08-30-2004, 12:56 PM
Well, I took the pullies off cause I noticed the crank pully was wobbling horribly. Now my stock pully does it too. Anyone know what I did wrong.
Dan

ThunderRoad
08-30-2004, 01:01 PM
Well, I took the pullies off cause I noticed the crank pully was wobbling horribly. Now my stock pully does it too. Anyone know what I did wrong.
Dan :confused: :confused: or is the balancer shot??????????? :confused: :eek: :eek: :eek:

AnnivSpeCpe
08-30-2004, 01:15 PM
Well, I took the pullies off cause I noticed the crank pully was wobbling horribly. Now my stock pully does it too. Anyone know what I did wrong.
Dan
Dan, is it possible that you installed the underdrive pulley off center? One of the bolt holes for the crank pulley is offset from the other three, which is meant to keep the stock pulley balanced and on-center with the stock hub. It IS possible with a bit of forcing to install the pulley off center. If this is the case the pulley may not be centered on the centering lip of the hub. This would definately cause the pulley to wobble "horribly". John

David Neibert
08-30-2004, 01:24 PM
John,

I think that is exactly what happened. Most people are not aware that one hole is slightly offset from the others and it's very difficult to get your head in there to see it, when installing the pulley.

David

edspringer
08-30-2004, 01:39 PM
I installed UD pulleys on both my 90 XR7 and 94 SC and found that one size does not fit all.

First, the XR7. Your tensioner jumping could be caused by a seizing alternator. Check to be sure the alternator spins freely when the UD pulley is installed. When I put the UD pulley on my XR7 alternator, the alternator would not spin at all. I had to shim it out with a 1/8th" spacer I got at my local hardware store. All is good in XR7 UD pulley land.

Now for the SC. First problem. I did not have the alternator problem as I did on the XR7, however, my belt was tooooooooooooooo close for comfort at the tensioner and the water pump UD. So I got four 1/4'' longer bolts and 1/4" spacers and put the spacers between the air conditioner and the A/C mounting bracket. This made the belt travel longer thus making the belt shorter and eliminating the need for a SPECIAL belt. Second SC problem. The crank UD pulley is a tight fit. The lip on the back of the pulley must fit square in the whole where the crank bolt fits. You might have to take a hammer and tap it in the hole to ensure a good fit. Mine fit OK there but the 4 holes would not line up. I tried all 4 possibilities. I finally drilled the holes out larger and got it to fit. It was not pretty but it does not wobble or come loose. Some blue Loctite made sure of that!

Bleed_Ford_Blue.......you might have cocked the UD crank pulley when you installed it. That could be the reason it wobbles. Your stock pulley probably wobbles because there is now probably a burr inside the balancer that the UD pulley created. I would CAREFULLY run a finger inside the hole and check for the burr.

Hope this helps!

Ed Springer

90 Black XR7 5-speed: 70mm TB, Fresh Air Intake, '94 Supercharger, 5% SC Pulley, Raised SC Top, I/C Fan, Underdrive Pulleys, 190 l/h Fuel Pump, 36# Injectors, Headers, Magnaflow Muffler (no cats) with stock resoantors, 3:27 Gears, Ripper Shifter, 73 CL MAF, Magnacore Wires, NGK Iridium Plugs and Rear Spring Air Bags.

94 Red SC Auto: 70mm TB, Fresh Air Intake, Stock 90 SC Pulley, Raised SC Top, I/C Fan, Underdrive Pulleys, 190 l/h Fuel Pump, 38# Injectors, Headers, Raven Muffler (no cats) with stock resoantors, 3:73 Gears, 73 CL MAF, Magnacore Wires, NGK Iridium Plugs, TRANSGO Shift Kit, ProTorque 2500 Stall TC, Haydon Auxiliary Transmission Cooler, Tokico Struts & Shocks, American Racing 17 Sniper Wheels, Michelin Pilot Sport A/S Tires and 235 RWHP with 315 Lbs.Ft. Torque.

Bleed_Ford_Blue
08-30-2004, 03:10 PM
You guys rock!!!

I checked the bolt hole spacing with dial calipers and yeah............

I didnt force it on and it hasnt been drilled but I left some nice thread marks in the bolt holes. I just used a little matco 3/8 ratchet, no cheater bars or anything. Hopefully I can figure out which hole on the balancer is the offset one and get this thing on right so I can drive my car. Hopefully the wobble hasnt caused any other damage.
Dan

AnnivSpeCpe
08-30-2004, 05:09 PM
Dan, Just a word. Avoid taking off the balancer if possible, because once taken off, the stock balancers are prone to failure. I'm sure you've heard this before as it's been commonly discussed. The alternative would be to remove the radiator to give you some space to look in there. I would try this first. Screw the four pulley bolts into the balancer, then take your calipers and measure the distance outside to outside of each of the four bolts. When you find the pairing with the smallest reading mark the balancer with chalk between the bolts with the shortest spacing. Then chalk the pulley between the shortest holes, then match em up. There ya go. John

Bleed_Ford_Blue
08-30-2004, 05:25 PM
I didnt have to remove the rad. to get in there. I just jumped on in. I found the best way was to just loosely bolt it up and try to slide the pulley down, it wouldnt go down really easily 3 ways but the fourth just slid right down. That must mean it isnt binding huh.

Thanks alot guys. You saved me a bunch of money. I was already shopping for a balancer thinking that was the problem. Thanks especially to dave for coaxing me through this. Another case of sc schmuckdom narrowly averted.

Bleed_Ford_Blue
08-30-2004, 11:07 PM
I didnt have to remove the rad. to get in there. I just jumped on in. I found the best way was to just loosely bolt it up and try to slide the pulley down, it wouldnt go down really easily 3 ways but the fourth just slid right down. That must mean it isnt binding huh.

Thanks alot guys. You saved me a bunch of money. I was already shopping for a balancer thinking that was the problem. Thanks especially to dave for coaxing me through this. Another case of sc schmuckdom narrowly averted.
It seemed to have worked guys