Car threw alternator belt.

[Blue Talon Boy]

Hey guys, my car threw its alternator belt yesterday. I picked up a new belt, installed it, and started it. It was fine at idle. I revved it, noticed idle was higher when it came down. First thought in my head was "wtf is my new belt at?" I found it under the car up against the garage door. Looked a little closer at the pulleys (keep in mind the alternator belt also turns the water pump). Alternator and water pump pulleys were lined up, crank pulley was a groove recessed into the timing cover.

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First thought in my head was crankwalk. This is a six bolt 1991 engine. However, I cannot push/pull the pulley. What could cause this? Where should I start my diagnosis?

 

[92AWDHX40]

Sounds like the balancer was rubbing against the cover,? right, alt belt could have been too tight.

 

[rts91tsi]

Your harmonic balancer has a rubber ring that connects it to the outer ring where the accessory belts ride. These normally separate, and deteriorate with age.

If you pull in and out on the pulley part, and then you'll know for sure if that is your issue.

 

[Blue Talon Boy]

Your harmonic balancer has a rubber ring that connects it to the outer ring where the accessory belts ride. These normally separate, and deteriorate with age.

If you pull in and out on the pulley part, and then you'll know for sure if that is your issue.

Thank, I'll take a look into that.

 

[rts91tsi]

I had my 93 do the same thing while it still had the 7 bolt in it, and I thought it was crankwalk.

If you can't get much movement pushing/pulling, or rocking it, then put the alternator belt back on. Start the car and watch the pulley to see if it is wobbling. If it is just starting to go it my not have enough play in it to tell by hand checking it, and needs the engine and accessory load to make it wobble and throw the belt.

 

[Blue Talon Boy]

Is this the type of damage I should be expecting to find?

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Also, after backing out the bolts (which I must mention, the big crank pulley bolt was not that tight) I was able to take the belt surface off the pulley with no problem.

 

[97ebaygst]

if you haven't figured it out yet check out jafro's garage page on youtube. he kept throwing the belt too. come to find out it was his block. the long bolt on the bottom of the alternator had worn out the block and allowed the alt to kinda turn where it sits which kept throwing the belt.

Crooked Alternator Bolt Fix [Dayjob Orchestra Mix] - YouTube

 

[rEclipserGST]

Time for a new one. Good thing you didn't do more damage while throwing that belt.

 

[rts91tsi]

Is this the type of damage I should be expecting to find?

Also, after backing out the bolts (which I must mention, the big crank pulley bolt was not that tight) I was able to take the belt surface off the pulley with no problem.

Just as I suspected.

It is too bad it ate into your timing belt cover, but at least it didn't take out the timing belt.

 

[Blue Talon Boy]

Just as I suspected.

It is too bad it ate into your timing belt cover, but at least it didn't take out the timing belt.

Yeah, I agree on both parts. The good news is, Autozone will have one for me in the morning.

Thanks to all that helped, especially rts91tsi.