Can't keep a belt on...

[losibrah]

The other night my serpintine belt came off of my 1993 SHO automatic. When I took it out of the engine bay, it looked like a normal old worn belt. I replaced it, and it ran fine all day. The next morning, it started making a metal on metal sound, almost like two pieces of metal rubbing together, and the belt was two or three ribs off on the crank pulley only. We took it off and reinstalled it, and it still slides off of the crank pulley. The mechanics in my area are VERY shady, and one told me I had a blown motor via cracked crank...... which I refuse to believe since my SHO has only 103,000 pampered miles on the odo, my oil is spotless and leaks are non-existant. I am very fond of my SHO! PLEASE HELP! And Thank You in advance.

 

[cetroutt]

check your all the pulleys that your belt rides on. if one is worn out or something is starting to lock up or drag it could cause your problem.

 

[Big D]

May need to shim some of the pulleys also...... check them to see if they're in alignment....

 

[hawkeye18]

A shot serpentine belt tensioner can cause those symptoms. Put the belt back on. Now press on it between the alternator and water pump pulley. Can you move it any more than the tiniest bit? To the same between the WP and P/S pullies. It should be almost too tight to move with your fingers. If it deflects more than a fraction of an inch, that's why it's slipping off.

 

[artsho]

The force required to put the belt on should tell you.....How does your tensioner feel when you move it with a wrench?

 

[shospeed]

Maybe your pullies aren't aligning !!
Maybe when you took it off you left one of the idler pullies loose there for causing it to wouble and the pullies not to aling.
(Not on the top bolt but on the one acually holding the pullie to the tensioner)

 

[losibrah]

Thanks guys......The belt is pretty tight, not much give at all. All the dead pulleys seem to be moving freely with no play. Is there any reason the crank pulley would be sliding back and forth?? I'm 90% sure that's the problem. I just can't see how it's all bolted up down there. Thanks again...

 

[encryptshun]

OMG this same exact thing happend to me yesterday on the way home from work. my pully would always rattle till about 2k rpm and everything would be fine, but yesterday after i turned the ac on the car started running like shit and by like 1/4 mile from my house the belt came off i havent had a chance to look at it do to inclement weather but i hope its something easy.

Sorry to thread jack dude...

 

[losibrah]

It's all good! I came here to see if anybody else has had the same problem, hopefully this isn't something major. Checked the pulleys again....fine. Belt tension is tight. It "looks" as though the crank pulley has moved toward the engine about 1/4 to 3/8 of an inch....which is kinda scaring me a bit.

 

[frosho]

Search for "crank cancer." Sounds like you might have it. Or you're really lucky and the crank bolt just needs to be tightened. At the least, you should remove that crank pulley and inspect the woodruff key for damage/wear.

 

[losibrah]

I was just gonna ask if this could be a sign of the dreaded crank cancer I have been reading about. Way too much for my mechanical skill to fix though. Anybody know of a good mech in the Youngstown Ohio area?

 

[93rev2sev]

Most likely the rubber that holds the two pieces of crank pulley together has failed.

It's called (by me...) Crank Damper Separation.

It's not uncommon and the good news is that a new crank damper is probably all that's needed. It can be had (used) for about $25 and should take a competent wrench less than an hour to replace.

 

[38SHO]

I think your crank damper is screwed too, especially if it moves back and forth like that.....

and its not that hard to change as stated above

move the tensioner so the belt is relaxed, take the belt off the crank pulley, remove crank pulley bolt, use tool to remove crank pulley, make sure woodruff key doesn't have play or isn't chewed up, install new(used) good condition crank pulley, tighten bolt, install belt... finished


you might have to take off the passenger front wheel so you have room to work down there.... as its easiest to work from that hole to mess with the crank pulley and its bolt.......

it won't even take many tools, isn't the tensioner bolt a 14 or a 17mm?..... IIRC the crank pulley bolt is 19mm, as is the lugnuts to remove the wheel....... you might need a hammer, jackstands, and a crank pulley puller if your unlucky like most and the pulley is stuck on there.....

 

[jmpSHO]

I'm pretty sure the two idler pulles are different and if you mixed them up at some point it will cause the belt to slip off because they won't be aligned. I think if they are mixed up one sticks out too far.

 

[hawkeye18]

The tensioner bolt is 17mm, and the crank pulley bolt is 19mm. You will need an 8mm socket and a phillips head screwdriver to remove the passenger side splash shield after removing the wheel with a 19mm socket.

 

[shospeed]

Any pics?

 

[losibrah]

Thanks again guys. Time to get dirty I guess.......Keep ya posted.....Gave up. Can't get the GD pulley off. Tried the starter pop, wedges, strap wrench.....nothing.

 

[jmpSHO]

Did you get the bolt out? I called one of those mobile truck repair guys to get the bolt out mine and then I used a steering wheel puller to get the pulley off.

 

[losibrah]

Yup....Crank Pulley was toast. Took it to mech, he even had a hard time getting that bolt out. Should be good to go. Thanks again........