Pedestal-Mount Rocker Arm Shims
 

I'm in the process of bolting a set of FRPP roller rockers onto a set of E7TE heads that have a pedestal-mount rocker setup. As I was setting up the #1 cylinder, and measuring the lifter preload, it became apparent that I'm going to need to install shims between the rocker arm insert and the pedestal. I know that FRPP sells a shim kit, but I'm wondering why I can't use a smaller, stainless steel fender washer between the pedestal and the rocker insert if I can get one in the correct thickness. Any thoughts as to why this would be a bad idea? I'm needing a shim approximately 0.030" to 0.040" to get the preload to spec out correctly. As I would rather avoid the wait for the kit, I really don't see why the washer idea won't work, assuming a quality piece in the proper thickness. As always, though, I don't want to go forward with something that is going to cause me problems. Does anyone have any feedback?

Pedestal-Mount Rocker Arm Shims
 

This is a pretty old post so you probably have your questions answered by now but I bought some spacer washers at home depot that are thinner than a regular washer and am using them on my 302 between the nut and the rocker ball. Like you, I couldn't seen any reason why this wouldn't work.

I must admit that I am having a hell of a time getting the lifter preload correct. I started out turning the rocker nut down until I started to get some resistance to turning the pushrod and then put in the right number of spacers or the next closest pushrod length in order to require 1/2 to 1 more turn of the rocker nut. I figured that would give me about .04" of preload on the lifter. That doesn't seem to be right though as some valves seem to be held open when the lifter is on the heel of the cam.

If you have yours sorted out please advise me at to the procedure you used. I have installed an aftermarket cam and new lifters. The cam has a base radius smaller than the stock one so that's why I have to screw around with pushrods.

Thanks:-X10

Pedestal-Mount Rocker Arm Shims
 

I did get it resolved, though I used a shim kit from Crane. (I still think that thinner stainless steel washers would have worked, though). I basically used the process recommended by Crane, which is referenced in the link in the other post (and follows):

Fast and Easy Way to Check Hydraulic Lifter Preload when using Non-Adjustable Rocker Arms

With the cam, hydraulic lifters and pushrods in place, install your rocker arm assembly. Use the prescribed method in your repair manual and torque down all the valve train bolts in the proper sequence. Pick a cylinder that you are going to check. Hand rotate the engine in its normal direction of rotation until both valves are closed. You are on the compression cycle for that cylinder. (At this position the valve springs are at their least amount of tension making the job a little easier to do.)

Wait a few minutes, allowing the lifters to bleed down. Now, lay a rigid straightedge across the cylinder head, supporting it on the surface of the head where the valve cover gasket would go. Using a metal scribe and the straightedge, carefully scribe a line on both pushrods. Now carefully remove the torque from all valve train bolts, removing any pressure from the pushrods. Wait a few minutes for the pushrod seat in the hydraulic lifter to move back to the neutral position. Carefully scribe a new line on both pushrods.

Measure the distance between the two scribe marks, it represents the amount of lifter preload. If the lines are .020” to .060” apart you have proper lifter preload. If the lines are the same or less than .020” apart you have no or insufficient preload. If the lines are further apart than 060” you have excessive lifter preload.


My preload checked out at about 0.040" to 0.050" following the shimming, and I've had no problems since. Hope this helps. :-X22

Pedestal-Mount Rocker Arm Shims
 

Thanks, I will try that tonight.

Another problem I descovered last night is that one of my rocker nuts had a split in it. It took me a long time to reolize it but every time I tightened it down I had a hell of a time getting the socket off. My response was to curse the thing and wonder why it would be a different size than the rest. I got another nut so I'll go at it again tonight.

Thanks again:-X10 :-X12

Pedestal-Mount Rocker Arm Shims
 

Best of luck. I basically turned the crank until the one valve started to open (all pressure off of the opposite valve). I fully loosened the rocker arm off of the tension-free valve, laid a straight-edge (metal ruler) across the head (valve cover mounting surfaces), and scribed a mark on the pushrod per Crane's instructions. I then torqued the rocker arm down to approximately 3/4 to 1 turn, or 20 ft/lbs., and scribed another mark. All came out to 0.045" to 0.050" after shimming. My initial attempts (without shimming) were way off..... torquing the rocker arms down really sunk the pushrods into the lifters, probably 0.070" or more. Considering that I'd had the heads milled and added a performance cam sort of explained it, though, and the first round of shims corrected it to spec.

Pedestal-Mount Rocker Arm Shims