New noise in valvetrain... ugggh!
Thread Starter
Pro
Joined: Dec 2010
Posts: 508
Likes: 3
From: Tallahassee, FL
New noise in valvetrain... ugggh! UPDATE!
Pretty sure I know what lies ahead, but I'll put it out there anyway.
Just started happening, maybe 15 mins of total run time since I noticed it. Above the usual valvetrain clatter a squeaky almost scraping sound emerged. Sometimes it's there, sometimes not. Doesn't really change with RPMs
Narrowed it to driver's side. Pulled VC and inspected Pushrods and rockers. All look fine. Plugs are nicely colored. Think I'm looking at lifter with maybe a bad roller or maybe clocked? Not sure due to the frequency not changing with revs.
Not looking forward to tearing it down.
Vid:
Just started happening, maybe 15 mins of total run time since I noticed it. Above the usual valvetrain clatter a squeaky almost scraping sound emerged. Sometimes it's there, sometimes not. Doesn't really change with RPMs
Narrowed it to driver's side. Pulled VC and inspected Pushrods and rockers. All look fine. Plugs are nicely colored. Think I'm looking at lifter with maybe a bad roller or maybe clocked? Not sure due to the frequency not changing with revs.
Not looking forward to tearing it down.
Vid:
Last edited by FNFastZ06; Aug 31, 2013 at 11:33 AM. Reason: Resolved
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
I am not thinking lifter either. That almost sounds like air leak or something. I would check things out real well before going into the motor.
How is the AIR system, are the rubber hoses OK?
How is the AIR system, are the rubber hoses OK?
Thread Starter
Pro
Joined: Dec 2010
Posts: 508
Likes: 3
From: Tallahassee, FL
I sure hope that's it!
Thanks guys
Instructor
Joined: Jun 2012
Posts: 120
Likes: 6
From: Town and Country MO
I had a similar noise and thought it was a lifter too. I took my best stethoscope to it and it turned out to be coming from the fuel injector.
After a tank or two of injector cleaner and 10000 miles later it got much quieter, but never went away.
After a tank or two of injector cleaner and 10000 miles later it got much quieter, but never went away.
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Seafoam
Have you tried running most of a can of Seafoam through your gas tank? That stuff is magic.
Tech Contributor
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Pull the valve cover and examine the rockers , springs and pushrods.
C5 rockers are WELL KNOWN to PUKE out all the little needle bearings inside the rocker and it can make that noise.
IF,,,, that is the issue, recommend that you do the TRUNION UPGRADE and replace all the rocker trunions.
When you find the root cause,, take plenty of pictures!!!
:cheers :
Bill
C5 rockers are WELL KNOWN to PUKE out all the little needle bearings inside the rocker and it can make that noise.
IF,,,, that is the issue, recommend that you do the TRUNION UPGRADE and replace all the rocker trunions.
When you find the root cause,, take plenty of pictures!!!
:cheers :Bill
Team Owner
Joined: Mar 1999
Posts: 22,025
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From: At the beach in little Rhody
Thread Starter
Pro
Joined: Dec 2010
Posts: 508
Likes: 3
From: Tallahassee, FL
Pull the valve cover and examine the rockers , springs and pushrods.
C5 rockers are WELL KNOWN to PUKE out all the little needle bearings inside the rocker and it can make that noise.
IF,,,, that is the issue, recommend that you do the TRUNION UPGRADE and replace all the rocker trunions.
When you find the root cause,, take plenty of pictures!!!:cheers :
Bill
C5 rockers are WELL KNOWN to PUKE out all the little needle bearings inside the rocker and it can make that noise.
IF,,,, that is the issue, recommend that you do the TRUNION UPGRADE and replace all the rocker trunions.
When you find the root cause,, take plenty of pictures!!!
:cheers :Bill
I'll post the results.
Team Owner
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From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
I did remove and inspect all the rockers and pushrods, all fine. Springs are upgraded and all look great. Squealing is getting louder, still located around #5 intake. Sounds like a lifter roller is bad or maybe rotated and scraping on the cam. If that's the case, time for linked lifters and maybe a little more cam. Don't have the time or space to tear it apart (remodeling kitchen and 2 bathrooms), so it's going in to the shop tomorrow.
I'll post the results.
I'll post the results.
If you DO decide on links, I'd really recommend Morels.
Racer
Joined: Dec 2005
Posts: 287
Likes: 2
From: Bay Area California
I did remove and inspect all the rockers and pushrods, all fine. Springs are upgraded and all look great. Squealing is getting louder, still located around #5 intake. Sounds like a lifter roller is bad or maybe rotated and scraping on the cam. If that's the case, time for linked lifters and maybe a little more cam. Don't have the time or space to tear it apart (remodeling kitchen and 2 bathrooms), so it's going in to the shop tomorrow.
I'll post the results.
I'll post the results.
This may be your problem or hopefully a failing lifter. My final install included retaining stock rockers, LS7 lifters and a different cam manufacturer with a different profile. Did cost money, but excellent performance gain with new cam was worth it. Best of luck...
A1
Racer
Joined: Dec 2005
Posts: 287
Likes: 2
From: Bay Area California
A1
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
Unfortunately, I too had the same/similar valvetrain noise occur to my H/C engine. Progressively became worse. Removed Crane 1.8 rockers and replaced with original stock rockers (with trunion modification) with no improvement. Simply became worse. Towing resulted to avoid additional damage. Teardown revealed cam lobes completely trenched out apparently due to improper heat treatment of the Crane cam. One lifter had slightly turned as a result thus a scraping sound. (FYI, aftermarket springs were correct rates thus not suspect of contibuting to failure.)
This may be your problem or hopefully a failing lifter. My final install included retaining stock rockers, LS7 lifters and a different cam manufacturer with a different profile. Did cost money, but excellent performance gain with new cam was worth it. Best of luck...
A1
This may be your problem or hopefully a failing lifter. My final install included retaining stock rockers, LS7 lifters and a different cam manufacturer with a different profile. Did cost money, but excellent performance gain with new cam was worth it. Best of luck...
A1