Hello

About 2 months or so back I had a lifter collapse I thought it was just a random failure of a new part. I had recently replaced cam, heads, lifters. I switched to a roller cam with trick flow heads.

The first lifter failed after the car was run and then shutdown and then restarted within 3 minutes upon restart it instantly started clicking but after a few min of running it pumped up and ran fine until it was shut down. It did this for a few cycles then failed to pump back up and was replaced.

The 2nd lifter failed on the opposite side of the engine about in the same place and almost exactly the same way as the first.

Im running comp roller lifters link bar style retro fit. The heads are trick flow twisted wedge and came pre assembled and designed to work with hydraulic roller cams. Spring pressure open is 376 lbs and Trick flow says this is suitable for use with hydraulic lifters and DOES NOT require any spring changes.

The odds of two lifters failing the same way within a few months of each other simply because I got two bad ones in a batch of 16 seems almost astronomical considering my last set of 16 ran almost 100k miles maybe more and were all working 100% fine when I removed them.

are there any ideas out there?

I cant keep pulling the heads off this thing every 1000 miles or so...

Thanks

-Gun

 

Hi,
I'm running TWs, and Comp's Link bars in my 49 year old block and have been for a couple of years with no problems to date.
Have you discussed this issue with Comp?
Did you do the P/R Geo routine?
Have you dissected the offending lifter(s) at the time of their failure?
Where is the pre-load set? I run about 1/2, or so.

 

Do you have oil pressure issues? I am wondering if your lifters are getting enough volume / pressure etc?
Just a thought?

 

I make 25 to 30 psi idle at 750 rpm and 64 psi above 1900 rpm.

Per the instructions im running 1 turn preload...maybe an issue???

Did you do the P/R Geo routine? .........I have no idea what that is...do tell.

I have been talking with comp...

Im probably going to disassemble this lifter...The way they are built you have to drill out the link bar rivet to remove the guts...its reallly stupid.

Thanks guys!

 

I usually run 1/2 to 3/4 turn preload. How are you finding 'zero tolerance' on the lifters? By spinning the pushrods? You should be trying to wiggle the rods up and down rather than spinning them.

 

Here are my thoughts.

trick flow instructions say 1/2-3/4 turn past 0 clearance.

DID YOU MEASURE AND CHECK THE CORRECT LENGTH FOR THE PUSHRODS? If not the improper length pushrod will actually change the ratio of the rocker arm. If this is the case and you are running close on cam lift in comparision to the allowed lift of the valve spring, coupled with the full turn of the lifter tension, you may be bottoming out the lifter and the pressure is causing it to collapse.

ask me how I know? 2 years of valve train issues will teach you a lot.

 

Billy has a great point! Worth a look.

 

Huh??

 

Billy

The pushrod lenght is dead on. I used an adj pushrod tool the wear mark is dead center on the valve stem.

its sorta sounding at this point that this one or both failed because it sucked up a piece of debris....Comp is going to look into it for me.

 

When you set the length of the pushrod did you use a solid lifter or the ones you have now?