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Help! valve train damage!
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Joined: Apr 2007
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From: Brookings SD
Help! valve train damage!
Fellas I am one bummed SOB! I put a cam and supercharger on my 01 Z06. Put on roller rockers and such, long story short I went to start the and it rolled over way easy so I figured no compression pushrods must be too long. I took of the pass. side valve cover off and here all the intake valves are bent and broke all the rocker arm bosses! I took off the driver side and everything is mint! WTF This really blows cause now I have a trashed set of fully cnc ported ls6 heads and dont know what the heck is going on!
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Joined: Apr 2007
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From: Forney Texas
Fellas I am one bummed SOB! I put a cam and supercharger on my 01 Z06. Put on roller rockers and such, long story short I went to start the and it rolled over way easy so I figured no compression pushrods must be too long. I took of the pass. side valve cover off and here all the intake valves are bent and broke all the rocker arm bosses! I took off the driver side and everything is mint! WTF This really blows cause now I have a trashed set of fully cnc ported ls6 heads and dont know what the heck is going on!
Either way, sorry for your loss. I am in the process of rebuilding my motor from a broken valve that destroyed 1 head and 1 piston, so believe me when I say I feel your pain!
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Fellas I am one bummed SOB! I put a cam and supercharger on my 01 Z06. Put on roller rockers and such, long story short I went to start the and it rolled over way easy so I figured no compression pushrods must be too long. I took of the pass. side valve cover off and here all the intake valves are bent and broke all the rocker arm bosses! I took off the driver side and everything is mint! WTF This really blows cause now I have a trashed set of fully cnc ported ls6 heads and dont know what the heck is going on!
HOLY CRAP!
I am JUST finishing up a Heads/Cam/push rods/ caddy lifters/ FAST90 intake/90 TB LS2 /Timing chain/ powerbond damper/42 lb/hr injector MOD tonight and this happens to you. MAN,,,,,,,,,,,,,,,,,,,,,,,Turing that ignition key for the first time is going to be a BITCH! 
I'm VERY methodical; almost to the point of being overly cautious when I do mechanical repairs,,,so,,,I really shouldn't be worried BUT,,,,,,,,,,,,,,you know how you can worry about unforeseen things. I'm really sorry you had problems like that.
I hope you can work through the problems and find the smoking gun!
Bill Curlee
Melting Slicks
Joined: Dec 2003
Posts: 3,315
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From: Near Jacksonville Fl.
Even if the cam timing was off I can't see it damaging only 1 head, something else must be really wrong.
BTW 2 things in life you NEVER DO, don't **** off Leroy Brown and don't ever change a cam without checking PTV clearence on both banks!
Good luck with your repairs, and check and recheck everything before trying to start the engine.
BTW 2 things in life you NEVER DO, don't **** off Leroy Brown and don't ever change a cam without checking PTV clearence on both banks!
Good luck with your repairs, and check and recheck everything before trying to start the engine.
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Joined: Apr 2007
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From: Brookings SD
The cam that came out was .580 lift and the one I put in was a blower cam that is .590 lift with non adj 1.7 roller rockers. Ive installed many cams, so I know the cam timing is right. I used the same pushrods. It was some major interferance like 1/4 inch I would say to break the heads bend the pushrods and valves. Only thing I can come up with is theres a bullitan (hes a mechanic) at work that says if you do not set the valves with each cylinder at TDC valve train damage will accur. So that seams to be the only thing I can come up with that makes any sence what so ever.
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
The cam that came out was .580 lift and the one I put in was a blower cam that is .590 lift with non adj 1.7 roller rockers. Ive installed many cams, so I know the cam timing is right. I used the same pushrods. It was some major interferance like 1/4 inch I would say to break the heads bend the pushrods and valves. Only thing I can come up with is theres a bullitan (hes a mechanic) at work that says if you do not set the valves with each cylinder at TDC valve train damage will accur. So that seams to be the only thing I can come up with that makes any sence what so ever.
BC
Team Owner
Joined: Mar 1999
Posts: 22,025
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From: At the beach in little Rhody
The cam that came out was .580 lift and the one I put in was a blower cam that is .590 lift with non adj 1.7 roller rockers. Ive installed many cams, so I know the cam timing is right. I used the same pushrods. It was some major interferance like 1/4 inch I would say to break the heads bend the pushrods and valves. Only thing I can come up with is theres a bullitan (hes a mechanic) at work that says if you do not set the valves with each cylinder at TDC valve train damage will accur. So that seams to be the only thing I can come up with that makes any sence what so ever.
I think what he meant is that each lifter has to be on the base circle to tighten the rocker. Here is the correct GM procedure:
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From: Forney Texas
Looks like in the picture that the cam is 180 out eh??
Tech Contributor
Joined: Dec 1999
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Ok.....I don't understand why one would need to rotate the engine to TOP DEAD CENTER of each cylinders compression stroke to install rockers for that specific cylinder.
If number one is at TDC, the timing marks are all lined up and you install all the rockers without moving the engine, all the pistons will be at the CORRECT position relative to the can lobe position s for that pistons stroke as well as the others.
Am I not seeing something here that I'm suppose to????
Some one PLEASE explain this to me because I JUST did this very install (have not moved the eng of #1 TDC yet ) and need to know I I'm fuked
Bill C
If number one is at TDC, the timing marks are all lined up and you install all the rockers without moving the engine, all the pistons will be at the CORRECT position relative to the can lobe position s for that pistons stroke as well as the others.
Am I not seeing something here that I'm suppose to????
Some one PLEASE explain this to me because I JUST did this very install (have not moved the eng of #1 TDC yet
) and need to know I I'm fuked Bill C
Tech Contributor
Joined: Apr 2007
Posts: 10,924
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From: Forney Texas
Ok.....I don't understand why one would need to rotate the engine to TOP DEAD CENTER of each cylinders compression stroke to install rockers for that specific cylinder.
If number one is at TDC, the timing marks are all lined up and you install all the rockers without moving the engine, all the pistons will be at the CORRECT position relative to the can lobe position s for that pistons stroke as well as the others.
Am I not seeing something here that I'm suppose to????
Some one PLEASE explain this to me because I JUST did this very install (have not moved the eng of #1 TDC yet ) and need to know I I'm fuked
Bill C
If number one is at TDC, the timing marks are all lined up and you install all the rockers without moving the engine, all the pistons will be at the CORRECT position relative to the can lobe position s for that pistons stroke as well as the others.
Am I not seeing something here that I'm suppose to????
Some one PLEASE explain this to me because I JUST did this very install (have not moved the eng of #1 TDC yet
) and need to know I I'm fuked Bill C
You're right about what you're saying. The thing is that you never want to tighten down a rocker arm when the lifter is not on the base circle of the cam. This will put extreme stress on the bolts, head etc. if you try to cinch down a rocker arm when it is anywhere on the lobe of the cam.
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
BLOWNBLUEZ06
This is TWICE in one day that you have given me some excellent information!
Well,,I did install the rockers without doing the base circle procedure and everything seemed to work out fine. Now I know why THANK YOU for some more excellent info.
BC
This is TWICE in one day that you have given me some excellent information!
Well,,I did install the rockers without doing the base circle procedure and everything seemed to work out fine. Now I know why THANK YOU for some more excellent info. BC
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Joined: Apr 2007
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From: Brookings SD
With the Harland Sharp rockers it looks like they came with pedistals for the rockers to sit on to do away with the factory one. Thats what I came up with anyway, there were no instructions for installation?
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From: Forney Texas
I don't think anyone on this forum could possibly begin to repay you for your contributions to this forum. I am always more than happy to share and even more with a man whom has been so generous!
Bret
