bad ASP underdrive pulley
#1
Staging Lane
Thread Starter
Join Date: Jul 2002
Location: englishtown n.j.
Posts: 58
Likes: 0
Received 0 Likes
on
0 Posts
![](https://ls1tech.com/forums/images/ranks/ls1tech10year.png)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
I read about a few timing chain breaks and some mentioned the ASP underdrive pulley possibly being the cause.
I am in the middle of a cam & head upgrade and I discovered that my pulley was bad.
It has two cracks in the insulation material between the inner and outer material
![](http://img.photobucket.com/albums/v202/mrjones69/heads/pulley6776.jpg)
The outer portion can be easily rotated 1/2".
you also can feel some front to back movement between the two pieces.
I did get a little belt noise. it would go away after a few minutes of running, no thrown belts.
pulley is about six years old. 33,000 mixed miles, no winter salt.
The timing chain looks good. There are no signs of binding links (rollmaster double)
no excessive stretch.
Looks like an ATI pulley will be the replacement.
I am in the middle of a cam & head upgrade and I discovered that my pulley was bad.
It has two cracks in the insulation material between the inner and outer material
![](http://img.photobucket.com/albums/v202/mrjones69/heads/pulley6776.jpg)
The outer portion can be easily rotated 1/2".
you also can feel some front to back movement between the two pieces.
I did get a little belt noise. it would go away after a few minutes of running, no thrown belts.
pulley is about six years old. 33,000 mixed miles, no winter salt.
The timing chain looks good. There are no signs of binding links (rollmaster double)
no excessive stretch.
Looks like an ATI pulley will be the replacement.
#7
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Harmonic balancer absorbs vibrations also known as harmonics which would usually vibrate the engine apart. timing chains and valve usually the first victims when one goes bad.
Trending Topics
#8
TECH Resident
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Thanks for the info. I will keep that in mind.
If you have a balancer that failed, could there be a bigger problem internally (something causing excessive vibe) ??
From the balancers that have failed...are they being heated before installing them?? Too much heat would definitely affect the lifespan of a rubber-type component.
If you have a balancer that failed, could there be a bigger problem internally (something causing excessive vibe) ??
From the balancers that have failed...are they being heated before installing them?? Too much heat would definitely affect the lifespan of a rubber-type component.
#9
Staging Lane
Thread Starter
Join Date: Jul 2002
Location: englishtown n.j.
Posts: 58
Likes: 0
Received 0 Likes
on
0 Posts
![](https://ls1tech.com/forums/images/ranks/ls1tech10year.png)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
I put this on so long ago I don't remember if I heated it.
If I did it would have been only slightly in a oven.
I did some searching and the powerbond underdrive pulley is tempting.
The price is 1/2 the ATI pulley. I did find some issues with the cam also-excessive wear in some lobes.
If I did it would have been only slightly in a oven.
I did some searching and the powerbond underdrive pulley is tempting.
The price is 1/2 the ATI pulley. I did find some issues with the cam also-excessive wear in some lobes.