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Old 08-20-2012, 05:16 PM
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cobalt327 cobalt327 is offline
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Originally Posted by Silver Surfer View Post
...there are so many people that say twist the pushrod until there is resistence while tightening the nut, or wiggle jiggle pushrods until they stop moving. I guess this is more of an issue with OEM stamped steel rockers and the ball and socket trunnion and/or OEM nut. Perhaps there just isn't enough tactile feedback that the system us now at 0 lash.
Jiggling the p-rod up and down as the clearance is removed allows you to hear and feel when zero lash is reached. Most guys find this easiest. This is mentioned at #4, here.

What don't you like about this swipe mark I posted? I looked and it doesn't appear that I can't dissassemble these lifters easily. I think most lifters have a normal snap ring, but these Comp Cams lifters have some sort of bent wire retainer. I am not sure I can get them apart with my tools/skills without damaging them. I will do some research and see what I can come up with.
The witness mark you show actually looks good. What I meant was getting the witness mark while holding down on the valve side of the rocker while cycling the engine seems like a bit of a hassle to get right.

It's because you are at minus 0.200" from the stock length of 7.8" that I'd like to see the measurement verified. If not for that, I'd say the witness mark was OK. I've not used the rockers you're using- it could be they're responsible for the difference.

The lifters will disassemble easily. Compress the p-rod cup w/a pushrod. While the cup pushed down away from the snap ring, pop the snap ring out using a small screw driver or pick. A disassembled lifter can be seen here. You can use wheel bearing grease to fill the chamber- the grease won't ooze out under the pressure of a checking spring.

I have a solid lifter, but the pushrod cup is quite a bit lower than where the plunger sits on a hydraulic lifter.
That's a problem- I'd recommend you use a hydraulic lifter made solid.

Do you mean use a stamped rocker? I do have the old self aligning rockers from the Vortec laying around.
Sure. The tip will not give you as sharp of a swipe mark as the roller tip, but it should be enough to give you a good idea of any large-ish change in the swipe's position on the valve tip.

I wasn't meaning to swap all 16 lifters permanently. I meant just use a solid lifter for checking geometry (I have a new one laying around). More on that in the next post.
My mistake- I misunderstood you.

Last edited by cobalt327; 08-20-2012 at 05:22 PM.
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