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arbs_53
09-22-2008, 05:09 AM
A few weeks ago, I pulled the head off my 250 in order to have a machine shop drill out a broken intake manifold stud. Yesterday I was going to put the head back on, but before doing so, thought I would pull the tappets out to inspect them. Found one that was pitted. Cam lobe is fine. Wanted to post a picture but I have no website.
My questions now are: Do I need to re-cut the tubular push-rod to fit the new tappet I will be getting? I'm thinking I can make up the slight difference by setting valve lash. Secondly, how do I handle the break in of tappet? Or, are break-in procedures primarily for the cam, which is fine with over 3000 miles on it?

Brosky
09-22-2008, 10:13 AM
Dave,

Sorry to hear about your problem. In order to help we would need some pictures to show the condition of the lifter(s) in question.

BUT first.....I don't believe that you will cut a push rod to fit a tappet for any reason, unless you shaved the head and changed the head thickness considerably. And even then, you would replace them with shorter rods that are readily available.

Now for an example, is this what you are referring to as "pitting"?

PeterK
09-22-2008, 10:24 AM
Dave,
Just replace the tappet. Go to Butler and get some assembly lube or come over and I'll give you a dab of cam assembly lube to smear on it, add some extra ZDDP to your new oil. Butler also sells EOS (ZDDP additive that you add to your oil. Then start it and run @2500rpm fpr 20 minutes, just to be sure. I think that's all you'll need.

You can post a picture directly from your hard drive. Click Full Screen reply at the bottom, then in the new window, click on File Manager below the reply window.

PK

arbs_53
09-22-2008, 10:27 AM
Paul,

My tappet had very few pits in it; nothing like your #1 set. Similar to your #2 intake, but with a couple of more pits.
The reason for my question about the pushrod is because the head was shaved to give me 9.5:12 compression. And I know the pushrods were custom fitted. But I shouldn't need to have this one pushrod re-sized, do I? I mean, whatever difference there is in a new tappet would probably be able to be accounted for in setting the valve lash. Right?

Brosky
09-22-2008, 10:29 AM
You are correct. Your rods are already to size. Just replace the tappet and follow Peter's advice with the additive.

I'm glad that your lifters did not look like mine. The two lobes were beginning to wear down as well.

arbs_53
09-22-2008, 10:32 AM
Thanks, guys. That's what I wanted to hear.

PeterK
09-22-2008, 01:27 PM
Dave,

The pushrod is the thing that was resized to account for the amount that your head was shaved. So the tappet height remains constant.

Bring cookies! (Dave makes great cookies)

DNK
09-22-2008, 03:56 PM
Cookie Party at Dave's :laugh:

arbs_53
09-23-2008, 06:00 AM
No problem. Just BYOM. (bring your own milk).