Valve adjusting [Archive] - Chevelle Tech

: Valve adjusting


69-CHVL
Feb 1st, 06, 7:38 AM
After adjusting the valves using the EOIC method, I noticed all the rockers are tight when at TDC. In other words, I can't wiggle them. I went a 1/4 turn. I tought they should jiggle a little after being adjusted. They did jiggle slightly when the motor had the net-lash system. The way I adjusted them was jiggle pushrod till no jiggle, and then tighten 1/4 turn.

GRN69CHV
Feb 1st, 06, 8:18 AM
Don't mistake "jiggling" the pushrod until it won't move at all with just adjusting the rocker until lash is just taken out. Very easy to overtighten the rockers and squeeze the oil out of the lifter. Have to find that exact point where the pushrod just makes complete contact with the rocker and lifter.

PS - I do not use the "spin" the pushrod method at all. With my bigger than large hands and grip to match, I find I can still spin the pushrod even when under load and have in the past over adjusted my rockers - more than once.

69-CHVL
Feb 4th, 06, 11:20 AM
Its funny how I can do so much, yet I can't adjust a valve!

After the valve is properly adjusted, should the rocker wiggle slightly?

Bob West
Feb 4th, 06, 12:50 PM
Hydraulic cam? I adjust them by moving the pushrod up and down til the play is gone, then run in it and adjust the dirty way, back off til clatter,tighten til clatter is gone then 1/4-1/2 turn. You will get a little wiggle ;)

69-CHVL
Feb 4th, 06, 12:57 PM
Yep, hydraulic roller. I'd do them running, but I just don't want to dirty everything up. Rather do them now and be down w/it. Got the intake off.

I guess peoples idea of zero-lash differs. My zero lash seems to be too tight!

Bob West
Feb 4th, 06, 1:06 PM
I think you'll have better luck finding zero lash moving the pushrods up and down, with the eoic method. I'm never far off at all doing it that way, but I like the dirty method for verification :D

greg_moreira
Feb 4th, 06, 1:49 PM
In case youve never heard this trick.....if ya got an old set of valve covers, cut the tops off(you only need one valve cover really), put em on and fire it up to adjust things with the dirty method. Although its still by no means a spotless job, the valve covers being on will help keep the oil from getting everywhere(to a degree) and of course you have access to the rockers with the tops cut off. Give that a shot if it comes down to adjusting them while running.

69-CHVL
Feb 4th, 06, 2:48 PM
Yea, I better do the running method. At least that way I'll know I got 'em adjusted right for sure. Its not good for me to keep screwing w/them right now cause the nut/rockers starts wearing the more I play with it.

Thanks guys.