Pilot Bushing?
Thread Starter
Intermediate
Joined: Sep 2006
Posts: 36
Likes: 0
Pilot Bushing?
Had heads installed on the car last week...
After getting home form the Dyno pulls.....The ca sounded like it had a belt squealing....but coming from under the car...
Pulled off the belts just to make sure the noise wasnt a belt....
for sure is coming from under the engine clutch area...thought it maybe the TO bearing but the noise dont change when I push the clutch in ...
Thoughts??
After getting home form the Dyno pulls.....The ca sounded like it had a belt squealing....but coming from under the car...
Pulled off the belts just to make sure the noise wasnt a belt....
for sure is coming from under the engine clutch area...thought it maybe the TO bearing but the noise dont change when I push the clutch in ...
Thoughts??
Burning Brakes
Joined: Sep 2007
Posts: 838
Likes: 8
From: Newbury Park CA
I just started having the exact same problem w/ my car. Took the belts off too and today I used a stethoscope to pin point that the noise is coming from somewhere between the throwout bearing and the back of the motor. I removed inspection cover and couldnt see anything out of order either. Also, the sound goes away on acceleration and only comes when motor is at full operating temp. Im trying to figure out if the sound is the pilot bearing or t.b.
Anyone else have this problem?
Anyone else have this problem?
Melting Slicks
Joined: Apr 2003
Posts: 2,285
Likes: 16
From: Nashville TN
I have had both go bad before. Hard to describe but I'll try. The throw out bearing will sound more like a roaring sound. Most noticeable when at idle and neutral with the clutch in. The pilot bearing is more squeaky and sounds like needles rattling around in a can. Most noticeable when at idle in neutral and clutch out.
Either way you have to pull the drive line, so you might as well replace both.
Either way you have to pull the drive line, so you might as well replace both.
Pro
Joined: Feb 2006
Posts: 594
Likes: 5
From: O Fallon MO
I am so glad I found this post!! I too have the same noise after a head and cam install. My tuner thought it was a balancer bolt coming loose but it was good. I also replaced my belt that came with my Powerbond balancer(looked cheap???). My noise comes only at operating temp as well and can be heard at idle. My tuner told me to look into an intake gasket leaking but it sounds too metallic to be that in my opinion. I did order a new clutch set up including hydraulics since I am having slipping issues with the new found power so I'll have it all out in a couple of weeks to check it out. I was even thinking that it was my MAP leaking in the FAST 90???
Chris
Chris
Thread Starter
Intermediate
Joined: Sep 2006
Posts: 36
Likes: 0
I am so glad I found this post!! I too have the same noise after a head and cam install. My tuner thought it was a balancer bolt coming loose but it was good. I also replaced my belt that came with my Powerbond balancer(looked cheap???). My noise comes only at operating temp as well and can be heard at idle. My tuner told me to look into an intake gasket leaking but it sounds too metallic to be that in my opinion. I did order a new clutch set up including hydraulics since I am having slipping issues with the new found power so I'll have it all out in a couple of weeks to check it out. I was even thinking that it was my MAP leaking in the FAST 90???
Chris
Chris
Update:::::::::::
It was after my head install the mine started and after looking at everything it turned out to be the motor was building to much vacum....We were looking at it at a local shop and it was warmed up and making the noise...We pulled the oil cap off while the car was running and the motor made a sucking noise the it stopped making the noise....I replaced the oil cap with a breather cap and it has never done it again....
Pro
Joined: Feb 2006
Posts: 594
Likes: 5
From: O Fallon MO
Update:::::::::::
It was after my head install the mine started and after looking at everything it turned out to be the motor was building to much vacum....We were looking at it at a local shop and it was warmed up and making the noise...We pulled the oil cap off while the car was running and the motor made a sucking noise the it stopped making the noise....I replaced the oil cap with a breather cap and it has never done it again....
It was after my head install the mine started and after looking at everything it turned out to be the motor was building to much vacum....We were looking at it at a local shop and it was warmed up and making the noise...We pulled the oil cap off while the car was running and the motor made a sucking noise the it stopped making the noise....I replaced the oil cap with a breather cap and it has never done it again....
I still am baffled at what can a head swap do to cause this condition?
Thanks
Chris
Last edited by cwalsh; May 3, 2008 at 10:00 PM.
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Thread Starter
Intermediate
Joined: Sep 2006
Posts: 36
Likes: 0
I know it was what fixed my car bro....If I didnt see it with my own eyes I would have thought ..."No Way"
I was told that a good valve job may have something to do with it...My Tuner said they have this alot in stroker motors and that it means my rings and valve job are good....dont see how that is but I know a breather cap fixed mine.....
PM sent
I was told that a good valve job may have something to do with it...My Tuner said they have this alot in stroker motors and that it means my rings and valve job are good....dont see how that is but I know a breather cap fixed mine.....
PM sent
Thread Starter
Intermediate
Joined: Sep 2006
Posts: 36
Likes: 0
Also the breather cap they sell for an LS1 is too tall for our cars...You have to remove the cover and the black filler neck and mount the breather on the valve cover with out the small black neck that is on it now.....Hope this helps
Burning Brakes
Joined: Sep 2007
Posts: 838
Likes: 8
From: Newbury Park CA
If any one has any further help or advice relating to the original topic it would be greatly appreciated. Once again referring to a centrifigal metal squeal at operating temp that comes from the bottom between the rear cover and the inspection cover, and sounds similar to a tensioner bearing noise. I dont think mine is vacuum related as the sound is coming from the bottom behind the motor closer to the driveline
Last edited by stroked408; May 13, 2008 at 01:52 AM.
Thread Starter
Intermediate
Joined: Sep 2006
Posts: 36
Likes: 0
If any one has any further help or advice relating to the original topic it would be greatly appreciated. Once again referring to a centrifigal metal squeal at operating temp that comes from the bottom between the rear cover and the inspection cover, and sounds similar to a tensioner bearing noise. I dont think mine is vacuum related as the sound is coming from the bottom behind the motor closer to the driveline
Since I started the Thread and this was the Original topic and fix........
That is where mine was coming from also and it turned out to be a vacum problem.....That is how the topic changed on us because the problem was found and fixed with a vent breather, and a few other problems were solved too from this thread...I never would have thought that was my problem with how it sounded......Good luck in your search...thoses noises will drive you crazy
Last edited by Take 2; May 13, 2008 at 02:52 PM.
Pro
Joined: Feb 2006
Posts: 594
Likes: 5
From: O Fallon MO
I second Take2 on this. I found that when warm and the squeal noise was there that if I removed the oil cap it went away. I also looked a little harder and found I was choking down the hose that goes from the right valve cover going to fresh air. I have since installed a quality piece of 3/8" hose and from what I can tell it is much better but still needs a breather.
Chris
Chris
Le Mans Master
Joined: Nov 2005
Posts: 5,451
Likes: 2
From: East Peoria Illinois
I have had both go bad before. Hard to describe but I'll try. The throw out bearing will sound more like a roaring sound. Most noticeable when at idle and neutral with the clutch in. The pilot bearing is more squeaky and sounds like needles rattling around in a can. Most noticeable when at idle in neutral and clutch out.
Either way you have to pull the drive line, so you might as well replace both.
Either way you have to pull the drive line, so you might as well replace both.