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realbold
07-04-2009, 09:58 AM
Crane roller rockers, hyd lifters. I heard zero lash, is this true anyone?

BlownCrewCab
07-04-2009, 10:04 AM
Zero lash, then between 1/2 and 3/4 turn more and you'll be set. Rocker arm style doesn't matter.

mrfixxall
07-04-2009, 10:32 AM
Crane roller rockers, hyd lifters. I heard zero lash, is this true anyone?

what crewcab said,also it bepends on what style lifter.i go 0 lash then 1/4 turn,some lifers can only be compressed .100, i do mine a 1/4 because if their were ever a ptoblem with your lifters they can pump up and cause valve damage so 1/4 turn will only allow the lifter to pump up .025.

MOP
07-04-2009, 01:33 PM
I copied this a few years back it may be of interest to others reading this post!

How to adjust hydraulic lifters
OK guys...thought I would share another of my top priority secrets...how to adjust your hydraulic lifters in 2 easy steps. This system works and I have been using it for years...but...take note...I said HYDRAULIC lifters...not solids.

Lets suppose that you have just installed a new cam and lifters (hydraulic flat tappet or hydraulic rollers) and you want to know how to set them. First off...do not set the intake manifold or your MPI intake on the motor until you have all those puppies adjusted so that you can see the cam to VERIFY that the lifter is indeed on the heel (back side of the cam from the lobe) of the cam and the lobe is on the other side. Leave the timing cover off too.

If you are using the same pushrods and rockers...the pushrod **MUST** go back in the **EXACT** spot it was in when you removed it, with the correct end **UP**. Also, the **EXACT** same rocker arm **MUST** go back on the **EXACT** same stud with the **EXACT** same **BALL** that was in that rocker arm. I can not stress enough...how important this is...because if you get just 1 wrong...that means 2 are wrong and you WILL HAVE DISASTROUS FAILURE with the 2 that are wrong. If you are installing NEW pushrods and rockers...no worries...just drop em in place and adjust.

OK...set the motor on TDC so that the 2 dots on the timing crank gear and the cam sprocket are lined up vertically. We are discussing a SB or a BB...doesnt matter, the firing order is the same (1-8-4-3-6-5-7-2). We want to look at the position of the cam lobe in relation to #1 cylinder...which is the first cylinder to your right as you stand in front of the motor...that side has 1, 3, 5 & 7, cylinders...the other side has 2, 4, 6 & 8 cylinders. Look at the cam at where the lifters are touching it. If it is NOT on the lobe or close to it, then you are correct for your starting point. If you can see the lifter beginning to start up the lobe on the cam, then you need to rotate the motor 1 full (360 degrees on the crank gear) turn and line up the 2 vertical dots again (crank gear dot will be on top and cam gear dot will be on top). With this done, we are ready to start adjusting...just make sure that you look into the intake ports to know that you are either on an intake valve or an exhaust valve. If you are using new lifters, there will be no resistance so you need to pay close attention and watch. Hold the pushrod with your thumb and finger...you can jiggle it up and down some...tighten the nut on the rocker until the pushrod has no jiggle or up & down movement. It should be just starting to push down on the plunger in the lifter. Mark that spot and then take your socket and make "ONE FULL (360 degree) TURN and stop at your mark spot...do NOT go more than one full turn. You might be able to push the rocker down alittle...if you have new lifters that are not pumped up...this is normal...no worries. Do this to adjust every lifter in this sequence which will be 8 lifters. The ones to adjust are...

If the harmonic balancer is on...line the mark up so that it on TDC and ready for number 1 to fire...then you can adjust...

INTAKE...3, 4, 6 & 8 valves
EXHAUST...2, 5, 6 & 7 valves

Now rotate the engine over by HAND 1 full turn (360 degrees) and line the marks up again and you can adjust the following after you verify that the lifter on #3 intake is on the heal of the cam...

INTAKE...1, 2, 5 & 7 valves
EXHAUST...1, 3, 4 & 8 valves

Now rotate the motor over by hand again 1 full turn. The lifters are all adjusted and now you can go back and button it up....install the timing cover and your intake. Set your distributor in place noting where the rotor is pointing as this will be where the #1 spark plug wire goes, then install the rest of the wires in a CLOCKWISE rotation. Some people rotate their motors to the 12, 3, 6 & 9 o'clock positions to do this, but I am lazy and prefer to do it in 2 steps instead of 4.

As I said, I have been using this methoid of hydraulic lifter adjustment for over 45 years and I have never had a problem. Adjusting solid lifters is a different game. I hope this will help anyone who might be doing engine mods as this is really pretty simple. Also I would not use the cork or rubber gaskets that go on the front and rear of the motor. I would instead use a 1/4 inch bead of silicone on the front and rear rail to ensure no oil leaks. It never fails with me to have the rubber strips squirt out when I am tightening up the intake manifold bolts...25 to 30 pounds feet of torque...so I toss those things and use the silicone...use high temp silicone.

realbold
07-04-2009, 07:03 PM
Thanks for the feedback. Much appreciated.

MOP
07-04-2009, 08:02 PM
Who's lifters do you have that can also have a bearing on what the lash is, I would do a search. Some performance gains can be had getting it right for your particular setup.

Phil

Rootsy
07-04-2009, 09:59 PM
Pre-load the lifters at least .030. With 20 threads per inch on a 7/16 rocker stud or 24 on a 3/8 stud that's about .040 - .050 / revolution after zero lash. One turn is A-OK.

Easiest way to adjust valves is to start at TDC on #1 and adjust the #1 I and E. Then rotate the engine 90 degrees and adjust #8 and then another 90 just following the firing order. 1-8-4-3-6-5-7-2... You'll make 2 compete revolutions of the crank before you are finished.