C5 head question
Thread Starter
Racer
Joined: Nov 2006
Posts: 297
Likes: 26
From: San Jose California
C5 head question
I just spent a day installing Helicoils in the head of my wife's 2004 Olds Alero. The studs that hold the rocker arm assembly onto the head pulled out, Has anyone had the same problem with their C5 ??
Burning Brakes
Joined: Jan 2006
Posts: 788
Likes: 105
From: Olathe Kansas
You could get this on LS1/LS6 heads, but I doubt its very common.
You'd need a HUGE cam to put that stress on the rocker system.. And anyone
who would be in that range would have already updated to a rocker stud type system .
On a pushrod V8, you just have one valve per stud/bolt.
Those aleros engines had lots of head gasket issues too. So probably just a thin casting to start with
You'd need a HUGE cam to put that stress on the rocker system.. And anyone
who would be in that range would have already updated to a rocker stud type system .
On a pushrod V8, you just have one valve per stud/bolt.
Those aleros engines had lots of head gasket issues too. So probably just a thin casting to start with
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
Never on the Corvette. There is a lot of thread engagement with the stock setup. With my aftermarket setup, I made sure I had a long thread engagement as well.
Just to add to the prior post, most of the issues I have seen with LS1/LS6 heads were due to either over tightening, too little thread engagement or cross threading. Reduced thread engagement was typically the result of aftermarket rockers, shims and stock or aftermarket bolts that simply weren't long enough to ensure enough thread engagement.
I did have issues with a Nissan years ago, had to heli-coil several of the rocker threads.
Just to add to the prior post, most of the issues I have seen with LS1/LS6 heads were due to either over tightening, too little thread engagement or cross threading. Reduced thread engagement was typically the result of aftermarket rockers, shims and stock or aftermarket bolts that simply weren't long enough to ensure enough thread engagement.
I did have issues with a Nissan years ago, had to heli-coil several of the rocker threads.
Pro
Joined: Feb 2013
Posts: 535
Likes: 92
From: Raleigh NC
It's a good idea to rotate the engine so that the cam is on the base circle for the rocker you are tightening. That way you aren't trying to compressor the valve spring with the threads of the rocker bolt. Of course this is easier when the engine is on the stand.
Instructor
Joined: Dec 2017
Posts: 139
Likes: 44
From: Fort Worth, TX
This is extremely common on the 2001+ 60 degree V6 as they moved to a smaller bolt with fine threads. I had the same issue on a 2004 3400. I bought the Time-Sert kit (VERY highly recommended). It was a bad design on the 3100/3400.
Last edited by digitaloutsider; Feb 16, 2018 at 11:00 AM.
