Lifter preload

[Custom Deluxe]

Got my Harland rockers mounted, measuring for pushrod length. Bring hydraulic lifters what is a good preload? I was thinking .075”. I have my pushrod length with no preload just need to know how much to add. I measured the plunger on one lifter and was ruffly .200” plunge.

 

[DieselAmateur]

I think I saw @Twisted Steel Performance mention that 0.050" is the preload for measuring length but hopefully he chimes in to clarify.

How are you measuring the pushrod length, just a simple ruler/ tape measure or ? If you're willing to share some info/ pics I've always been curious as to how this process is done

 

[Twisted Steel Performance]

As long as you are using a pushrod length checking rod, add .050" for preload.

And you do know hs rockers use a 5/16 ball pushrod on the rocker end...

 

[Custom Deluxe]

I think I saw @Twisted Steel Performance mention that 0.050" is the preload for measuring length but hopefully he chimes in to clarify.

How are you measuring the pushrod length, just a simple ruler/ tape measure or ? If you're willing to share some info/ pics I've always been curious as to how this process is done

Yea just using pushrod checker snap gauge style. I just leave the intake and exh rockers on the cylinder I’m checking to make it easier.

As long as you are using a pushrod length checking rod, add .050" for preload.

And you do know hs rockers use a 5/16 ball pushrod on the rocker end...

Thank you for responding. Yes the 5/16 on the rocker side. I was thinking of using 5/16 ball on both ends as from what I can tell the lifter cup is 11/32.

 

[DieselAmateur]

@Custom Deluxe what do you mean by snap gauge style? I've seen the adjustable pushrods for finding length that just screw/ unscrew for adjustment that are then measured with calipers.

How does the stock length compare to what you've measured for using with the Harland rockers? Are you using the 1.6 non adjustable ratio?

 

[Custom Deluxe]

@Custom Deluxe what do you mean by snap gauge style? I've seen the adjustable pushrods for finding length that just screw/ unscrew for adjustment that are then measured with calipers.

How does the stock length compare to what you've measured for using with the Harland rockers? Are you using the 1.6 non adjustable ratio?

I’m trying to use 1.7 non adjustable with .070 gasket. The length with .050 preload was shorter than stock. It’s not a standard pushrod checker got it from summit works slick. Still use calipers for final measurement.

 

[Twisted Steel Performance]

Well you will need to clearance the heads or they will bind, and the valves will be very close if not touching the pistons.

 

[Twisted Steel Performance]

If a .070 gasket still makes the rod length shorter than stock either the block or heads have had a lot machined off...

 

[Custom Deluxe]

Good point I’ll recheck. Maybe I wasn’t on the base circle or the lifter didn’t drop. The motor looks brand new inside, might have just been rebuilt. It’s a military take out. The heads didn’t seem cut and the piston to deck was stock, unless they used a different pin height piston. At .075” preload would have put me at a stock length pushrod.

 

[DieselAmateur]

got a link/ part # for the tool?