Getting to 0 lash 273 rockers hydraulic cam

-
S

Shadow

Well-Known Member
Joined
Mar 11, 2013
Messages
117
Reaction score
13
Location
Porterville ca
Wanting to adjust valves on 340 with 273 rockers
on hydraulic lifters. Have read on other threads to get
the cam on the lowest point for selected
rocker ( that part is easy enough for me )
then rotate pushrod with fingers while tightening
adjuster until pushrod becomes a little stiff to turn. I now have 0 lash? This is where I need to make sure that this is correct.
Then I'm guessing that the adjusters (273 stock)
are either 16 or 18 threads per inch so to achieve .030
of preload I would tighten the adjuster another 1/2 turn?
Does all this sound correct or am I missing something?
 
The adjuster thread is 3/8-24.
That's just under .042" per turn.
Some guys here are preloading as little as .010".
Being hydraulic, you have a fairly large range of "acceptable".
Do a search, you'll find quite a bit of info.
 
Sound real good to me.

The easy way to get .030 is to mark the push rod at the valve cover surface, then turn your half of a turn and see how far the push rod moves.

You may have to give it a minute or two to collapse the lifter. but once you figure out how much of a turn you need on the first one you can just adj all the rest. Make sure you are on the base circle of each one you do!!!!
 
Sounds like I'm on the right track then I just need to give each lifter a couple minutes
to settle before I start the process.
 
I've read "rotate the pushrod" in most every single magazine all my life and I think it's the stupidest bullshittiest way to do it. I simply grab the pushrod between my thumb and index finger as I am tightening down the adjuster and pull and push gently on the pushrod up and down until I have no play left without depressing the lifter plunger. Using the turning the pushrod method, it is very easy to misjudge because all the surfaces the pushrod is rubbing against and the pushrod itself are all very smooth and do not provide a good source of friction for judgment. ESPECIALLY when everything is lubed up good with prelube oil. Pulling and pushing the pushrod gently up and down is a much more accurate way to judge when all of the play is out. It is also very easy to determine if you are depressing the lifter plunger. All this of course is my opinion, it's how I do it. It's worked well for me.
 
Just don't cross the line.... Or.... Kaboom!!!!
 
I agree with rusty rat rod. Just gently push up and down until the slack goes away while turn in the adjuster - then one full turn on the adjuster and away you go to the next one. Crane cams specifies 20 to 60 thousandths preload, one turn is about 40.
 
I also agree with Rusty. Up and down with the pushrod or rock the rocker arm back and forth. Half turn should be good. tmm
 
Ok I will try up and down on the pushrod, I tried to "rock" the rocker itself
to determine when I was getting to zero lash but
that just wasn't working for me, had no sence of feel
But I didn't try grabbing the pushrod for up and down, only if it rotated
really easy where it didn't seem like there was any pressure from
the lifter
 
You must log in or register to reply here.
-

Back
Top