advice needed: roller rocker install, setting lash

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87fox72mach

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1995 firebird rebuilt motor 5 spd dail driver
1987 grand wagoneer plow truck
1987 mustang lx 5.0 work custom engine bay and paint
1972 mach 1 project
hey guys im slowly putting my motor together. im at the point where im putting on my rocker arms on. they are the crane gold rocker arms. I also installed the crane guideplate conversion kit. now my question is where do I begin installing the rocker arms to set the lash I was unable to located any good info and setting lash. any help is appreciated as always!

 
Hydraulic or solid lifters?

There are two schools for either setup:

The scientific procedure that involves dial indicators and rocker arm angle.

The every day mechanic procedure that involves centering the pushrod in the hydraulic

lifter or gaping the the clearance between arm and valve stem on a solid

lifter motor.

 
Alex,

I just re-adjusted mine after re-torqueing the rocker studs on my Model A.

Go to the Comp Cams website & look up the installation for their roller rocker (which I have) It has a detailed description on sequence & how to adjust. Your Cranes should be typical or check their website also.

Good luck, call me if you have any questions.

Thanks, Jay

 
Thanks for the replies. I've done the adjustment once before on my 87 5.0. But at that time I was replacing one valve spring at a time so I adjusted rockers at that time

 
I've wondered the same thing. I used COMP cams instruction sheet exactly, however the rockers make a tapping noise. It really makes me nervous about it. My oil pressure is 70lbs Cold and 37 Hot so I know its OK, just the noise is abnormal.

 
I've wondered the same thing. I used COMP cams instruction sheet exactly, however the rockers make a tapping noise. It really makes me nervous about it. My oil pressure is 70lbs Cold and 37 Hot so I know its OK, just the noise is abnormal.
Might need an additional 1/8 - 1/4 turn. Basically if the lifter is at rest (no pressure on the valve) there should be just a tiny bit of play.

 
I've wondered the same thing. I used COMP cams instruction sheet exactly, however the rockers make a tapping noise. It really makes me nervous about it. My oil pressure is 70lbs Cold and 37 Hot so I know its OK, just the noise is abnormal.
thats because lots of comp lifters are c__p . . buy cranes.


the comp video is just get make an engine run . . it is not even close to correct as far as how to "properly" set valve train geometry.

check out these from professional engine builders.


 
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Can any of you list exactly what you bought. My valvetrain is loud and I think it is wrong length pushrods so I think this would be an easy fix with performance upside.

 
I watched the video above and many say its wrong. I heard 1/2 turn once zero lash is reached is proper?

 
I watched the video above and many say its wrong. I heard 1/2 turn once zero lash is reached is proper?
My shop manual gives three positions for the balancer to be in...TDC, rotated 180 deg clockwise, and rotated 270 deg or 3/4 turn, and the appropriate valves to adjust in each position. I usually rotate the push rods with my fingers while tightening the rocker until the pushrod quits rotating freely. I then take it down another 3/4 turn.

This has always worked for me with stock camshafts. Of course you need to mark your balancer correctly.....I use a straight edge and start with the timing mark at top dead center (at pointer) at one end of the straight edge and lay the straight edge across the balancer with the center of the mounting bolt directly under the edge....it helps if the fan and shroud have been removed. I then mark the balancer opposite the TDC mark. The other mark (at 90 and 270 degrees) is a little more difficult to make and I usually just "wing" it but you could get really fussy and use a small sliding carpenters "square" if winging it bothers you .....

View attachment 27843

valve adj 351c 002.JPG

 
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this video was super helpful
 
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