Big Block Valve Lash

[dstrbdxp-AK]

I recently picked up a nice 77 Blazer w/ big block. The motor is definitely decked out with some good stuff, pistons, cams, all crane valvetrain, edelbrock fuel goodies.

I'm slowly making my way through it and am going to be changing out header gaskets, setting the valve and tuning it this weekend. I wouldn't normally be too worried except I can hear a bit of a tap coming from the right bank at idle.

How tight is recommended?

 

[4X4HIGH]

The very first thing you need to know is if the cam is hydraulic or solid lifter. If it is hydraulic then you can set the valve adjustment with the engine running. You start the engine, start to loosen a rocker nut until that valve is "clacking" at you then slowly start to tighten the valve until the clack goes away then another 1/2 turn on the rocker nut. Now move to the next valve and do the same.

 

[dstrbdxp-AK]

I have no build specs other than the obvious visuals so I will have to pull a rocker arm and peak down in.

 

[4X4HIGH]

I have no build specs other than the obvious visuals so I will have to pull a rocker arm and peak down in.

A hydraulic lifter and solid lifter look identical so that won't do you any good. You need to bring the engine up to TDC and see if there is any clearance between the rocker arm and the tip of the valve. It would be highly unlikely that someone would have installed a solid lifter cam and left no valve clearance at the rocker. It is probably a hydraulic cam BUT you need to make 100% sure before adjusting them like a hydraulic.

 

[dstrbdxp-AK]

Is there a difference between the retaining clips?

 

[4X4HIGH]

Is there a difference between the retaining clips?

Retaining clips? Are you talking about the little clip that holds the lifter plunger in the lifter body? If so then there is no difference.

 

[JDNobodi]

Don't the high "quality" hydraulic lifters come with a better snap ring that makes look like a solid?

 

[dstrbdxp-AK]

Just curious but how noisy should a full roller top end be? I reset the top end and both banks give off a tapping sound, as if a lifter isn't pumping up, or set too tight.

Also, is there a recommended temp for setting roller rockers? Hot or cold? Hot metal will obviously have expanded then contract when cold, which could give a bit more noise when cold. But mine hasnt gone away. Runs like a top, just a chattery top end.

 

[4X4HIGH]

Roller rockers are noisy and if you're running aluminum valve covers then the noise will be even louder than with a steel valve cover.

 

[dstrbdxp-AK]

Luckily the chatter doesnt get louder w/ RPM