Failed lifters?
Thread Starter
Racer
Joined: May 2010
Posts: 359
Likes: 0
From: Seattle WA
Failed lifters?
I had engine failure on track last season - engine started to overheat and then shutdown. 15-20 min later it started with horrible drivetrain noise and reduced power, but it made it home 50 miles.
I took heads off and found out that half of the lifters have pushrod end plates pushed much further into lifter body than others.
The one that look normal measures 4 mm from plate to top edge, while other 7-8mm!
Oil has fine metal paste in it, but no metal pieces.
Questions:
1. Why valves are ok? Most of them stayed closed all the time, which explains overheating, right?
2. I am going to replace lifters, head and exhaust gaskets, head bolts.
Anything else?
3. Should I replace T-chain and oil pump, while I am almost there?
4. How to assure that bottom end is ok? I really prefer not to take engine out of the car.
Thank you for your help.
I took heads off and found out that half of the lifters have pushrod end plates pushed much further into lifter body than others.
The one that look normal measures 4 mm from plate to top edge, while other 7-8mm!
Oil has fine metal paste in it, but no metal pieces.
Questions:
1. Why valves are ok? Most of them stayed closed all the time, which explains overheating, right?
2. I am going to replace lifters, head and exhaust gaskets, head bolts.
Anything else?
3. Should I replace T-chain and oil pump, while I am almost there?
4. How to assure that bottom end is ok? I really prefer not to take engine out of the car.
Thank you for your help.
Last edited by sergeyk; Apr 5, 2013 at 02:19 AM. Reason: add pics
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Oil pump replacement is a MUST as well as the chain. If it were me, I would drop the oil pan and pop off the main caps and check the bearings. At least one anyway. If they are scored and full if trash, you will have to pull the engine. With the pan off, you canclean the junk out of the pan, and clean the pick up tube strainer
I would install NEW LIFTER BUCKETS also.
Bill
I would install NEW LIFTER BUCKETS also.
Bill
Thread Starter
Racer
Joined: May 2010
Posts: 359
Likes: 0
From: Seattle WA
Thread Starter
Racer
Joined: May 2010
Posts: 359
Likes: 0
From: Seattle WA
Oil pump replacement is a MUST as well as the chain. If it were me, I would drop the oil pan and pop off the main caps and check the bearings. At least one anyway. If they are scored and full if trash, you will have to pull the engine. With the pan off, you canclean the junk out of the pan, and clean the pick up tube strainer
I would install NEW LIFTER BUCKETS also.
Bill
I would install NEW LIFTER BUCKETS also.
Bill
Thread Starter
Racer
Joined: May 2010
Posts: 359
Likes: 0
From: Seattle WA
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Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
WOOPS,,,,,,, Replied the wrong answer to the wrong oil pan post. 
If you need to remove the pan, you will have to drop the cradel (K Member) and figure out a way to support the engine from the top. GM makes a special brace but, people have used other methods.
Sorry for the confusion.
Bill
If you need to remove the pan, you will have to drop the cradel (K Member) and figure out a way to support the engine from the top. GM makes a special brace but, people have used other methods.
Sorry for the confusion.
Bill
Safety Car
Joined: Aug 2011
Posts: 4,436
Likes: 403
From: Portland OR
I had engine failure on track last season - engine started to overheat and then shutdown. 15-20 min later it started with horrible drivetrain noise and reduced power, but it made it home 50 miles.
I took heads off and found out that half of the lifters have pushrod end plates pushed much further into lifter body than others.
The one that look normal measures 4 mm from plate to top edge, while other 7-8mm!
Oil has fine metal paste in it, but no metal pieces.
Questions:
1. Why valves are ok? Most of them stayed closed all the time, which explains overheating, right?
2. I am going to replace lifters, head and exhaust gaskets, head bolts.
Anything else?
3. Should I replace T-chain and oil pump, while I am almost there?
4. How to assure that bottom end is ok? I really prefer not to take engine out of the car
I took heads off and found out that half of the lifters have pushrod end plates pushed much further into lifter body than others.
The one that look normal measures 4 mm from plate to top edge, while other 7-8mm!
Oil has fine metal paste in it, but no metal pieces.
Questions:
1. Why valves are ok? Most of them stayed closed all the time, which explains overheating, right?
2. I am going to replace lifters, head and exhaust gaskets, head bolts.
Anything else?
3. Should I replace T-chain and oil pump, while I am almost there?
4. How to assure that bottom end is ok? I really prefer not to take engine out of the car
If there was enough goo/crud in the oil to cause the lifter plungers to get stuck, and if you overheated it that bad that it quit, I think you really need to remove the engine.
If you had a 2 piece pan, you would know for sure, but I just don't think you will get lucky by replacing the lifters and calling it good. That's a lot of work to find out after it's back together and running.
Don't you agree? Sometimes it's just best to follow your gut.
Ron
Instructor
Joined: Oct 2011
Posts: 138
Likes: 0
The 50 mile drive home didn't do you any favors.
I would pull motor, but I have alot of $ invested in mine, so I couldn't take the risk
I would replace timiing chain if its an ls1 chain. Mine blew at maybe 500hp. Don't wanna have to tear it all apart again
I would pull motor, but I have alot of $ invested in mine, so I couldn't take the risk
I would replace timiing chain if its an ls1 chain. Mine blew at maybe 500hp. Don't wanna have to tear it all apart again
Thread Starter
Racer
Joined: May 2010
Posts: 359
Likes: 0
From: Seattle WA
It's a GMPP timing chain, not LS1, so should be good.
Race Director
Joined: Jan 2008
Posts: 16,027
Likes: 169
From: oregon
oil pressure should be a good indicator of the bearings. excessive wear will create lower oil pressure. if oil pressure is good AND you have good cylinder leakdown numbers i would repair and run. pulling the pan cover for inspection seems reasonable though. if there is any crap from the 300deg oil you can clean it out
personally i will only use redline race oil on track days. 2000+ppm of zinc/phos and group 5 ester base. that stuff will not break down, sludge or vaporize at 300deg. most street oils are getting cooked at those temps.
one of the best all in 1 articles on oil, racing and temps i've found is here
http://ferrarichat.com/forum/faq.php?faq=haas_articles
personally i will only use redline race oil on track days. 2000+ppm of zinc/phos and group 5 ester base. that stuff will not break down, sludge or vaporize at 300deg. most street oils are getting cooked at those temps.
one of the best all in 1 articles on oil, racing and temps i've found is here
http://ferrarichat.com/forum/faq.php?faq=haas_articles
Last edited by racebum; Apr 6, 2013 at 05:13 PM.
Thread Starter
Racer
Joined: May 2010
Posts: 359
Likes: 0
From: Seattle WA
oil pressure should be a good indicator of the bearings. excessive wear will create lower oil pressure. if oil pressure is good AND you have good cylinder leakdown numbers i would repair and run. pulling the pan cover for inspection seems reasonable though. if there is any crap from the 300deg oil you can clean it out
personally i will only use redline race oil on track days. 2000+ppm of zinc/phos and group 5 ester base. that stuff will not break down, sludge or vaporize at 300deg. most street oils are getting cooked at those temps.
one of the best all in 1 articles on oil, racing and temps i've found is here
http://ferrarichat.com/forum/faq.php?faq=haas_articles
personally i will only use redline race oil on track days. 2000+ppm of zinc/phos and group 5 ester base. that stuff will not break down, sludge or vaporize at 300deg. most street oils are getting cooked at those temps.
one of the best all in 1 articles on oil, racing and temps i've found is here
http://ferrarichat.com/forum/faq.php?faq=haas_articles
Le Mans Master
Joined: Sep 2003
Posts: 6,253
Likes: 222
From: Farmington CT
Cruise-In VII Veteran
Which GMPP chain? The LS7 chain that is commonly referenced could also be called the LS1/2/3/4/6/7/9 and every chain that is used in 99up 4.8/5.3/6.0/etc. motors. 
The LS7 chain is often listed in 'sigs' and 'mod lists' as a 'MOD', it's simply an OEM replacement.
Getting to a main/rod bearing:
Look on the auction site, Kent Moore has 'Corvette engine cradles', along with a box steel tube will support the motor in a C5 with the cradle removed. Should take about 2 hours to remove the cradle.
I learned of the Kent Moore fixtures from Bret Bradbury(1000whp plus Texan)
They KM fixtures are almost mandatory when pulling a motor on the ground, ever try to install the cradle while the cherry picker is supporting the motor? the legs of the motor hoist make moving the cradle a pita.
After a few motor swaps you'll have the removal down to under 4 hours
The LS7 chain is often listed in 'sigs' and 'mod lists' as a 'MOD', it's simply an OEM replacement.
Getting to a main/rod bearing:
Look on the auction site, Kent Moore has 'Corvette engine cradles', along with a box steel tube will support the motor in a C5 with the cradle removed. Should take about 2 hours to remove the cradle.
I learned of the Kent Moore fixtures from Bret Bradbury(1000whp plus Texan)
They KM fixtures are almost mandatory when pulling a motor on the ground, ever try to install the cradle while the cherry picker is supporting the motor? the legs of the motor hoist make moving the cradle a pita.
After a few motor swaps you'll have the removal down to under 4 hours
Le Mans Master
Joined: Sep 2003
Posts: 6,253
Likes: 222
From: Farmington CT
Cruise-In VII Veteran
Katech rod bolts would be a good upgrade; not sure what valvesprings were used, age, heads milled, etc?
lot's of factors here
Instructor
Joined: Oct 2011
Posts: 138
Likes: 0
Which GMPP chain? The LS7 chain that is commonly referenced could also be called the LS1/2/3/4/6/7/9 and every chain that is used in 99up 4.8/5.3/6.0/etc. motors.
The LS7 chain is often listed in 'sigs' and 'mod lists' as a 'MOD', it's simply an OEM replacement.
The LS7 chain is often listed in 'sigs' and 'mod lists' as a 'MOD', it's simply an OEM replacement.
ls7 might be same chain, but either way, the ls2 I got was better than stock ls1 chain
Thread Starter
Racer
Joined: May 2010
Posts: 359
Likes: 0
From: Seattle WA
https://sdparts.com/details/gm-facto...parts/12586482