Generation III Internal Engine 1997-2006 LS1 | LS6
Sponsored by:
Sponsored by:

Clacking under the pressure.....

Thread Tools
 
Search this Thread
 
Old Jul 7, 2010 | 01:02 PM
  #1  
yamaharacer114's Avatar
Thread Starter
Teching In
 
Joined: Sep 2007
Posts: 28
Likes: 0
From: Romeo, MI
Exclamation Clacking under the pressure.....

As the sig states I have an 01' z28 w/ 93k on it, oil always changed religiously, well maintained, recent updates on the car are 7.350 hardened pushrods and ls7 lifters that went in just this past weekend. now on to the problem. While the motor is under heavy load, high torque, there is a LOUD clacking/clatter from the engine that follows the rpm. The harder/further the gas is depressed the louder and more frequent the sound becomes. Been working on trying to diagnose it but I am officially out of idea's. oil pressure when hot is damn near in the red when hot (according to factory gauge...going to replace) and around 25psi upon start up. Also about once every 2-3 weeks i will get a random multiple misfire code popping up. Any idea's? really need help here!
Reply
Old Jul 7, 2010 | 01:21 PM
  #2  
Sales2@Texas-speed's Avatar
LS1Tech Premium Sponsor
iTrader: (5)
 
Joined: Jan 2008
Posts: 5,053
Likes: 7
From: Texas!
Default

How much preload did those pushrods end up putting on your lifters?
__________________


Largest Stocking Distributor of LS-x Engines / CHECK OUT OUR NEW WEBSITE!

COMP - FAST - PACESETTER - DIAMOND RACING - EAGLE SPECIALTY PRODUCTS - CALLIES - COMETIC GASKETS
RAM CLUTCHES - MOSER ENGINEERING - KOOK'S HEADERS - ARP - GM BOLTS AND GASKETS - MSD - NGK
POWERBOND - ASP - AND MORE!
Reply
Old Jul 7, 2010 | 01:25 PM
  #3  
yamaharacer114's Avatar
Thread Starter
Teching In
 
Joined: Sep 2007
Posts: 28
Likes: 0
From: Romeo, MI
Default

I ended up doing the stupid thing and just slapping them in there to get the car ready to drive again, never payed attention to the amount of pre-load i put on them. but figured i would be going with the safer option with the shorter pushrods after the lifter install.
Reply
Old Jul 7, 2010 | 01:26 PM
  #4  
Sales2@Texas-speed's Avatar
LS1Tech Premium Sponsor
iTrader: (5)
 
Joined: Jan 2008
Posts: 5,053
Likes: 7
From: Texas!
Default

That'd be the first thing I'd check here!
__________________


Largest Stocking Distributor of LS-x Engines / CHECK OUT OUR NEW WEBSITE!

COMP - FAST - PACESETTER - DIAMOND RACING - EAGLE SPECIALTY PRODUCTS - CALLIES - COMETIC GASKETS
RAM CLUTCHES - MOSER ENGINEERING - KOOK'S HEADERS - ARP - GM BOLTS AND GASKETS - MSD - NGK
POWERBOND - ASP - AND MORE!
Reply
Old Jul 7, 2010 | 01:29 PM
  #5  
yamaharacer114's Avatar
Thread Starter
Teching In
 
Joined: Sep 2007
Posts: 28
Likes: 0
From: Romeo, MI
Default

do you think that the lifters dont have enough load on them or too much with the current pushrods?
Reply
Old Jul 7, 2010 | 01:52 PM
  #6  
Sales2@Texas-speed's Avatar
LS1Tech Premium Sponsor
iTrader: (5)
 
Joined: Jan 2008
Posts: 5,053
Likes: 7
From: Texas!
Default

With all that noise, I'd hazard a guess that they might not have enough...but there's only one way to know for sure.
__________________


Largest Stocking Distributor of LS-x Engines / CHECK OUT OUR NEW WEBSITE!

COMP - FAST - PACESETTER - DIAMOND RACING - EAGLE SPECIALTY PRODUCTS - CALLIES - COMETIC GASKETS
RAM CLUTCHES - MOSER ENGINEERING - KOOK'S HEADERS - ARP - GM BOLTS AND GASKETS - MSD - NGK
POWERBOND - ASP - AND MORE!
Reply
Old Jul 7, 2010 | 02:08 PM
  #7  
Adrenaline_Z's Avatar
TECH Resident
 
Joined: Dec 2004
Posts: 845
Likes: 0
From: K-W, Ontario
Default

That ^^^, and possibly the rocker arm contacting the retainer.

With a shorter pushrod, you're likely positioning the rocker arm incorrectly
and giving up some valve velocity as well.

Hopefully nothing is bent, or damaged.
Reply




All times are GMT -5. The time now is 06:08 PM.