A FEW QUESTIONS ABOUT LASH CAPS -----

Okay, I picked up a pair A429 aluminum CJ heads that have never been bolted to an engine. I didn't notice that there was a bag of Moroso lash caps in the box with the heads. What is the purpose of these, and are they compatible with a mechanical roller cam? Obviously, I've had no experience with them, or I wouldn't be asking such a potentially stupid question, so don't flame me too badly.

Wayne (SAWDOFF) Pearce

Can be for a couple of different uses

1) you have titanium valves that do not have the wear surface fused to the tip and a hardened lash cap is required for wear.

2) To help correct geometry issues due to rocker selection and valve length selection not being correct.

X2 what Dave said. I've used them for BOTH purposes. Even some stainless valve stems are soft on the tip and lash caps solve the problen of wearing a line thru the tip of the stem.

Okay, I understand that, but can they be used with a solid roller, what keeps them in place when you have a valve lash of let's say .017, won't they get hammered to death?

Wayne

No worries there, the typical "cup" on lash caps is around .060" most solid rollers usually only need .022 to .026 lash. Unless you float a valve or the valve touches something it isn't suppose to and bends. You shouldn't have any problems.

If you've ever tried pulling a cap off the valve tip you wouldn't be worried about it popping off. I think the rocker could come off completely and the cap would stay put. The oil makes a suction and seems to hold it there.

Another thing,though, the keepers need to have the groove on the top to allow for the cap.

norm wrote:If you've ever tried pulling a cap off the valve tip you wouldn't be worried about it popping off. I think the rocker could come off completely and the cap would stay put. The oil makes a suction and seems to hold it there.

Another thing,though, the keepers need to have the groove on the top to allow for the cap.

^^this^^if you use them be very sure you check how well they fit.if the cup is too deep or lets say the valve tips were cut causing the lash cap to contact the valve locks you'll have big problems.

Great points, I have seen this more times than not. Very simple to check the clearance. But over looked a good amount. Another thing to watch for is if the valves have a hardend tip already. But the tip is slightly bigger than the valve stem. I have seen the caps side load the tip and "kick" the tip off. Because the rocker was to far over center, or the "nose" and put all the pressure on the outside edge of the cap.

AndyLeslie wrote:Great points, I have seen this more times than not. Very simple to check the clearance. But over looked a good amount. Another thing to watch for is if the valves have a hardend tip already. But the tip is slightly bigger than the valve stem. I have seen the caps side load the tip and "kick" the tip off. Because the rocker was to far over center, or the "nose" and put all the pressure on the outside edge of the cap.

They are too be installed by someone whom knows how too setup a valvetrain.

Thank you, everybody for the responses.  My mind is now set at ease - not knowing about "tech issues" like this makes me very nervous, and hesitant to proceed.  These "toys" cost far too much to blow something up because I didn't ask first - thanks again.

Wayne

Nothin wrong w/asking ??? Wayne. Better than terrin something up.