how do you use one of these????


it looks like this

 

Usually they're marked with what the shortest length is... then they get longer as you unscrew them, usually .050" per turn (20 pitch thread such as ¼"-20)

Dummy one rocker up. Use a solid lifter if you have one; or a very light spring on the valve, just barely heavy enough to make it return. Or, use a hydraulic lifter and a dial indicator; put the engine at the position whe the particular valve is at exactly is point of maximum closing, which is at the point where the same type valve (intake or exhaust) on the cyl that's 4 cyls away in the firing order, is at exactly fully open (measured using the dial indicator); install the adjustable push rod at stock height for the rest of your valve train, for a starting point (7.300" for a roller cam, for example); put some gear marking compoiund or white lithoium grease on the tip of the valve; install the rocker on the closed valve, and adjust it while watching the deflection of the push rod end with the dial indicator, which will not change until the rocker reaches "zero lash", and note the dial indicator reading at that point, then continue to tighten the rocker until the rocker stops deflecting (you've reached the bottom of lifter plunger travel at that point), and note the dial indicator reading again, and subtract the 2 readings (we'll call this distance "lifter travel"). Rotate the engine through 2 complete crank rotations (one cam rotation); measure the width of the pattern on the valve tip that the rocker makes (that is, from teh intake side to the exhaust side of the valve stem, which tells you how far across the vale tip the rocker tip slid during its motion). Adjust the push rod one full turn longer, and do the same thing, and measure the width again. If it's shorter, adjust the PR longer, and repeat; if it gets longer, shorten the push rod, and repeat. The goal is to find the push rod length at which the rocker tip slides across the valve tip the least distance. Once you've found that length, check another valve.

If you did it with a hydraulic lifter, add the "lifter travel" you measured, to the push rod length you got by screwing and unscrewing it.

I do one of each type on each head. I've run across motors where the exhausts were different from the intakes, and the left bank was different from the right bank. If they're all within one .050" step (the increment you can buy push rods in), then you can get one set of 16 of the same length. More often than not, this is possible. But always check, just in case you have different valve locations.

 

I guess I'm lazy (and cheap). My "checking springs" are the old dampers that are pulled out of stock "throw-away" valve springs that are slightly elongated and installed to hold the valves closed. I've made length checkers from old push rods, some 12-24 or ¼-28 (can't remember) bolts, and jamb nuts. I've also used the quick-and-dirty Manley length checker. It simulates the correct position of a rocker arm when slid onto the stud, so all that's left to do is adjust the checker to length and measure it.

 

*No comment*

:sillylol:

 

Told you I was lazy.

 

No.

Nevermind. I guess you win a lot whan you play the game "Dirty Minds" don't ya?

Joke --- >
Vader's Head

 

AJ,

I got your point, but I was trying to stay above board (for a change). Unfortunately, I sometimes feel that I have to use a 1" mic to check those parts.

I have several good lines about that, but this isn't the correct forum, for sure.

 

Hey Vader,

How has your luck been with the manley rocker simulator?

I am thinking of going the lazy way?