Duncan_GT

Ok, so I've searched the past couple hours and am confused on how to find/adjust pushrod length. I just installed Crane hydraulic roller lifters (retrofit) for my hydraulic cam, part # CRN-36532-16. I also am installing Trickflow roller rocker arms, part # TFS-51400520. I have an adjustable pushrod length checker.

I have found articles of builds very similar to mine, in fact one was done by Trickflow. However, the pushrods used ranged everywhere from 7.6 to 8.5 (8.5 being what Trickflow used, however they did not use the same retrofit lifter I am.)

How do you check for pushrod length?

mjr46

if you are using the actually lifter, you'll need to install checking springs on the head/ remove current valve springs, , roll motor over until cam is on base circle of valve you'll be checking, install length checker and roll it out until you get a witness mark on the back center 1/3 of the stem, set poly lock, roll motor over then remove poly lock and inspect witness mark made, I use a sharpie to color the stem black, you are looking for the narrowest pattern but yet still remaining in the center 1/3 of the stem, I try various settings and compare.

Duncan_GT

I was hoping not to remove the springs, damn it. I don't know what you mean by the "back center 1/3 of the stem". I saw this in a different article but didn't understand what they were talking about

adrnlnjnky700

the stem that comes up through the middle of the spring on the head. there should be a thin mark on it in the center from the roller part of the rocker pressing down on it when it opens it.

Duncan_GT

Yeah I know where the witness mark should be. They are brand new heads/springs so there's no mark yet.

As for the "1/3 center", do you mean looking at the top of the valve stem (looking straight down at it means the top of the stem would be a circle), the 1/3 of the circle is when the valve is closed, the 1/2 mark is when the valve is half opened, and the final 1/3 opposite the side of the first is when the valve is fully opened? Since the rocker arm doesn't stay in one place as it rides the stem.

Am I thinking of this correctly? I may have worded that weird.

Duncan_GT

And how do I set the polylock when the length checker has been installed? I can't set the checker to zero lash, as spinning the rod is what lengthen/shortens it. Otherwise I'd be set.

mjr46

I just take out all the up and down movement out

mjr46

if you can't view this link, then you need to register at sbftech.com


http://sbftech.com/index.php/topic,317.0.html

Duncan_GT

Thank you for the link, that helps a lot when I get the correct length pushrods ordered. So with the length checker, i should tighten the adjuster nut til the pushrod doesnt move up and down? That article says to lock the nut, what is he talking about?

mjr46

lock nut, poly lock, = same thing