I've posted about this before but I need a littlle more information/guidance. I'm getting ready to remove the heads on my l98. They are trick flow twisted wedge sbc2. I understand I need to remove the push rods prior to removing the heads which will require removing the nut in the middle of the rocker. Now, it's pretty obvious this whole assembly is under pressure. Questions:

1. What is the procedure for removing the rods?
2. What is the procedure for putting it all back together and getting everything adjusted correctly?

I've done just about everything else to this engine with good results. I don't want to screw this up.

Steve

 

Removal is pretty easy. Unscrew the rocker arm nut, lift it off and then pull out the pushrod. For reassembly, with the lifters off the cam lobe, tighten the rocker arm to "0" lash and turn an additional 1/2 turn.

 

Thanks. One more question: What is 0 lash? I've heard it mentioned but no idea what it means.

 

Zero lash is when you tighten down the rocker nut while the lifter is on the base circle of the cam. You can easily wiggle the pushrod when the rocker nut is backed off. Tighten up the nut just to the point where the pushrod doesn't wiggle. That's zero lash.

Adjusting the rocker 1/2 turn more from zero lash will put around a 0.030" preload in the lifter. The hydraulic oil will bleed off and the pushrod will feel loose enough to spin again but don't tighten it any more. The maximum preload is around 3/4 of a turn and minimum is 1/4 turn so your 1/2 turn doesn't need to be 100% accurate.