Collapsed LS7 lifter.
Collapsed LS7 lifter. Just installed new heads & lifters.I noticed my oil pressure was lower than before..It wont make beyond 40-50 psi hot,& it drops below 20 at idle(closer to 15).
After about 200 miles, The engine starts to make a TAK-TAK-TAK sound..Holy **** it's loud!
It's coming from the the area right under the newly installed LS6 vally pan & behind the front cover /water pump..I pulled the #1 rocker arms & noticed very little oil splash on the #1 intake rocker.It's a Harland rebuild & the bearings inside the fulcrum are shot...As if it wasn't getting oil from the pushrod..
The oil pressure was fine before I did the head /lifter swap..Now it's not.
The oil pump is an LPE ported unit & I run Mobil 15-50 weight in accordance with what LPE told me to do.
Any ideas?
I'm at a loss & dont want to just start throwing parts at it...
After about 200 miles, The engine starts to make a TAK-TAK-TAK sound..Holy **** it's loud!
It's coming from the the area right under the newly installed LS6 vally pan & behind the front cover /water pump..I pulled the #1 rocker arms & noticed very little oil splash on the #1 intake rocker.It's a Harland rebuild & the bearings inside the fulcrum are shot...As if it wasn't getting oil from the pushrod..
The oil pressure was fine before I did the head /lifter swap..Now it's not.
The oil pump is an LPE ported unit & I run Mobil 15-50 weight in accordance with what LPE told me to do.
Any ideas?
I'm at a loss & dont want to just start throwing parts at it...
I would first confirm that oil is gettin to the valvetrain and go from there. Check the easy stuff first. Confirm oil hole in pushrod is free of obstruction. Fire engine up with valve cover off and confirm oil getting to the rockers would be my first move.
Originally Posted by Ryan02SS
I would first confirm that oil is gettin to the valvetrain and go from there. Check the easy stuff first. Confirm oil hole in pushrod is free of obstruction. Fire engine up with valve cover off and confirm oil getting to the rockers would be my first move.
I'll update as I figure stuff out.
Originally Posted by BYE RICE
Yeah..Starting the car sans valve cover doesn't work too well with valve cover mounted coil packs..But what I will do is remove all the spark plugs,pull both covers, & spin the engine over with the starter.That's how I primed it in the first place after prior to starting it with the new lifters installed.
I'll update as I figure stuff out.
I'll update as I figure stuff out.
Update...
The engine runs suprisingly well on one bank of cylinders...For a few miniutes I had the only 4 cylinder 4th gen in the world...It allowed me to determine I do, in fact, have a bad #1 intake lifter.I hooked up a mechanical pressure guage using an adapter where the filter goes..The needle buzzes around between 50-70 cold & falls to 25-45 hot.
We went a step further & removed the rocker arms & pushrods on #1 & pulled them up into their retainers using a pen magnet...We hooked up the 3,5,& 7 coils & ran it.
No noise.
Bad lifter
This is a brand new(<200 miles) GM LS7 lifter,PN 12499225
WTF?
The engine runs suprisingly well on one bank of cylinders...For a few miniutes I had the only 4 cylinder 4th gen in the world...It allowed me to determine I do, in fact, have a bad #1 intake lifter.I hooked up a mechanical pressure guage using an adapter where the filter goes..The needle buzzes around between 50-70 cold & falls to 25-45 hot.
We went a step further & removed the rocker arms & pushrods on #1 & pulled them up into their retainers using a pen magnet...We hooked up the 3,5,& 7 coils & ran it.
No noise.
Bad lifter
This is a brand new(<200 miles) GM LS7 lifter,PN 12499225
WTF?
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Originally Posted by BIG_MIKE2005
I also am very interested in what actually caused this problem. I will also be goin with LS7 lifters & Harland rebuild rockers very soon.
I have LS7 lifters and harland rebuilt rockers in an old coffee can soaking in oil in my garage, waiting for my new motor to get here
I want em good and oily when I put them in! I left this thead hanging..It wasnt a lifter.
I spun a rod bearing.
The sound was the piston hitting the quench pad.
I apologized to TSP for my "expert" diagnosis & had them build me a 383.
It all worked out..The 383 is AMAZING..It is one good running engine.
Imagine all the HP of an LS1 with torque EVERYWHERE.
The downtime enabled me to get my combination checked out & I learned alot of valuable information in regards to the heads I'm running & their initial shortcomings..(wrong CC)..That was adressed quickly by Texas Speed. Patrick G is truly a master at cam selection & is probably the biggest reason why this engine runs as well as it does.
The same can't be said about the clutch.It's shot.
Always something.But my LS7 lifters work GREAT!
I spun a rod bearing.
The sound was the piston hitting the quench pad.
I apologized to TSP for my "expert" diagnosis & had them build me a 383.
It all worked out..The 383 is AMAZING..It is one good running engine.
Imagine all the HP of an LS1 with torque EVERYWHERE.
The downtime enabled me to get my combination checked out & I learned alot of valuable information in regards to the heads I'm running & their initial shortcomings..(wrong CC)..That was adressed quickly by Texas Speed. Patrick G is truly a master at cam selection & is probably the biggest reason why this engine runs as well as it does.
The same can't be said about the clutch.It's shot.
Always something.But my LS7 lifters work GREAT!
Last edited by BYE RICE; Jul 9, 2007 at 08:58 AM.
