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Old 10-10-2011   #411
LGAFF
 
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Default Re: LT5 Assembly Project

Big setback, did and leakdown test and none of the valves hold pressure....all 8 cylinders failed, bigtime.....more to come.
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Old 10-11-2011   #412
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Default Re: LT5 Assembly Project

Didn't one of the FBI members run into similar issue about a year or so ago when the valves were a smidge too long after a valve job?

Gotta go do a search.....

BRB

Here it is:
http://www.zr1.net/forum/showpost.ph...0&postcount=25
Possibility?


TomC
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Last edited by tccrab; 10-11-2011 at 02:06 AM.
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Old 10-11-2011   #413
LGAFF
 
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Default Re: LT5 Assembly Project

Engine was tested with cams......
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Old 10-12-2011   #414
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Default Re: LT5 Assembly Project

Lee:

Didn't read through enough to see if you used new rings, but if you did then they're probably just not seated into the cylinder walls yet.

Perform standard engine break-in routine and then retest.

HTH!!!

TomC
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Old 10-12-2011   #415
Bob G
 
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Default Re: LT5 Assembly Project

Lee do you wan't to stop buy and check it out for you?
MR 134+
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Old 10-12-2011   #416
LGAFF
 
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Default Re: LT5 Assembly Project

Bob I am about 100% sure its a bad valve job......I am home today if you want to stop by......I pulled the D/S head and no marks on pistons, etc so appears nothing that I did....

Will be back home at 4:30 or so
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1991 ZR-1 #1359

Last edited by LGAFF; 10-12-2011 at 05:16 PM.
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Old 10-12-2011   #417
XfireZ51
 
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Default Re: LT5 Assembly Project

Quote:
Originally Posted by Bob G View Post
Lee do you wan't to stop buy and check it out for you?
MR 134+
Bob,

I didn't believe it when you said it, but you are even more insufferable at 134+mph than you were at 128!!!
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Old 10-13-2011   #418
Bob G
 
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Talking Re: LT5 Assembly Project

Don't You Just Love It
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Old 10-13-2011   #419
tccrab
 
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Default Re: LT5 Assembly Project

Quote:
Originally Posted by LGAFF View Post
Bob I am about 100% sure its a bad valve job......I am home today if you want to stop by......I pulled the D/S head and no marks on pistons, etc so appears nothing that I did....

Will be back home at 4:30 or so
Lee:

If you didn't do the valve job, then the million dollar question is who did the valve job and how on earth did they fubar it so bad?
One or two I could understand, but to goof up at least 1 valve on each cylinder seems highly unlikely.

TomC
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Old 10-13-2011   #420
LGAFF
 
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Default Re: LT5 Assembly Project

Very experienced shop, not sure what the story is at this time, will withhold any judgements until the verdict is in....lets not forget that these heads had a prior valve job and ate a screw.....so there could be alot of issues. I assembled the heads, etc....so maybe its something I did...

Maybe there is not even a problem......

But here is the main reason I am concerned.....this is at 45PSI




Exhaust valves:

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Last edited by LGAFF; 10-13-2011 at 10:05 PM.
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