Valve train Puzzle - Page 2 - ZR-1 Net Registry Forums

scottfab · 06-05-2013

Quote:

Originally Posted by LGAFF

The line manager at Mercury told me many of the race engines they tested broke cam chains related to oil starvation on the lower half of the motor at high RPM. He said people always think the chains are the weak point but its the oiling system pushing all of the oil to the top end of the motor; sudden stoppage snaps the chains.

Really sorry to see this happen. I see in the vid at 2:02 that the top chain guide in the valve cover is looking ok. Had you heard any piston slap before the event? Say at idle just after a cold start?
What oil were you using?
What mods were done to the engine if any?
This is not the worst I've see but as someone said. "it's rare".
We're ALL pulling for ya.
She's down but NOT out!

XfireZ51 · 06-05-2013

I don't see how busted chains sheared 2 cam bolts. Agree w Bob, something stopped the cams. In any case, you'll have the car ready for the next 1/2 mile.
Maybe in October.

LGAFF · 06-05-2013

Was there any damage to the cam bearing surface or cam lobes?

ALZR1 · 06-05-2013

Quote:

Originally Posted by XfireZ51

I don't see how busted chains sheared 2 cam bolts. Agree w Bob, something stopped the cams. In any case, you'll have the car ready for the next 1/2 mile.
Maybe in October.

the chain broke because of the lifter breaking and getting in the way of the cam turning,some of the lifter parts were stuck in the head.
the last oil used was AMSOIL 10/40 HIGH ZINC CONTENT,but I don't think
it was the oil that caused the failure.

AL.

ALZR1 · 06-05-2013

Quote:

Originally Posted by LGAFF

Was there any damage to the cam bearing surface or cam lobes?

not at all.

rhipsher · 06-05-2013

Is this the LPE stroker Al?

XfireZ51 · 06-05-2013

Quote:

Originally Posted by rhipsher

Is this the LPE stroker Al?

It's an FBI stroker

LGAFF · 06-05-2013

jeal lifters

Blue Flame Restorations · 06-05-2013

Sorry about your loss, Al....

I bet you'll get it running better than ever=D>

ALZR1 · 06-05-2013

Quote:

Originally Posted by Blue Flame Restorations

Sorry about your loss, Al....

I bet you'll get it running better than ever=D>

you got that right Bret.
it's and FBI stroker,but the problem is not with the bottom half.

AL.

06-05-2013	#12
XfireZ51 Join Date: May 2007 Location: Chicagoland, IL Posts: 9,696	Re: Valve train Puzzle I don't see how busted chains sheared 2 cam bolts. Agree w Bob, something stopped the cams. In any case, you'll have the car ready for the next 1/2 mile. Maybe in October. __________________ [SIGPIC][/SIGPIC]Former Membership Chairman Former ZR-1 Registry - BOD 1972 Corvette 4speed base Coupe SOLD long time ago 1984 Corvette Z-51/4+3 SOLD 1992 Corvette ZR-1 Aqua/Gray #474 SOLD 1992 Corvette ZR-1 Black Rose/Cognac #458 2014 Honda VFR Interceptor DX

06-05-2013	#13
LGAFF Join Date: Mar 2007 Location: Crystal Lake, IL Posts: 7,194	Re: Valve train Puzzle Was there any damage to the cam bearing surface or cam lobes? __________________ LGAFF 90 #966-150K miles-sold 92 #234-sold 1987 Callaway TT #17 1991 ZR-1 #1359

06-05-2013	#16
rhipsher Join Date: Aug 2008 Location: Houston 90 Red ZR-1 Posts: 2,320	Re: Valve train Puzzle Is this the LPE stroker Al?

06-05-2013	#18
LGAFF Join Date: Mar 2007 Location: Crystal Lake, IL Posts: 7,194	Re: Valve train Puzzle jeal lifters __________________ LGAFF 90 #966-150K miles-sold 92 #234-sold 1987 Callaway TT #17 1991 ZR-1 #1359

06-05-2013	#19
Blue Flame Restorations Join Date: Feb 2010 Location: Pendleton, IN Posts: 3,904	Re: Valve train Puzzle Sorry about your loss, Al.... I bet you'll get it running better than ever=D> __________________ 1988 KOH Prototype EX5023 sold 1990 ZR-1 #444 Convertible 1990 ZR-1 Black #966 1991 ZR-1 Quazar Blue #296 1957 Duntov SS Project