AK71CutlassS

So I bought a pushrod checking tool and I'm trying to figure out the correct pushrod length. Is there a way to do it without collapsing the hydraulic roller lifter? My heads are installed.
My steps I've been doing are as follows
- set the lifter on the base of cam lob
- Mark top of stem with marker
-set pushrod checker to zero lash and then a half turn more
- rotate engine 2 full revolutions
- then see where the mark is on valve stem and adjust accordingly
- is this correct? My initial measurement was 9.05 with the line in the middle of stem
I just did one valve so far ..being that I'm unsure

Thanks in advance

Tony

AK71CutlassS

well just finished my work week. Any info would be much appreciated

midrange

Everything sounds good.
I don't know that you need the extra half turn though when setting the zero lash to check length.

AK71CutlassS

Yeah like EFI said. I believe my lifter springs are collapsing a bit when I rotate engine. I have heads installed already so I'm wondering how I can get a solid lifter the same length as my erson hydraulic roller lifters... Ugh this is difficult

83hurstguy

last time I did this with a hydraulic flat tappet, I had two lifters that I disassembled, filled with epoxy, and reassembled so they couldn't collapse. Little more expensive to do with roller lifters.

Your process sounds good. Just remember that you aren't necessarily concerned with having the witness line on the valve tip be perfectly centered, but you want the least transverse "travel" across the valve tip possible to eliminate side loading (shown by the narrowest witness mark you can achieve). This is determined by having the rocker perpendicular to the valve at 50% lift.

gbledsoe3

I read this recently in BTR's book on measuring push rod length for hydraulic lifters:

"Using an adjustable pushrod to fill in the distance between rocker and lifter, add about .050 for hydraulic-lifter applications to give proper preload."

I can not attest to the validity of that statement, I'm only sharing what I read.

coppercutlass

If you are talking about when checking for proper length you are compressing the lifter plunger you can can buy a set of checking springs . they are like 15 bucks and are the way to go.

AK71CutlassS

That's the problem I really don't wanna take the heads back off

coppercutlass

You can change the springs with the heads on the engine. There is a tool for it and a procedure.

AK71CutlassS

Yeah. hmm this is really frustrating.