new cams are in on the rebuild and car has 11 miles on it, but the valvetrain is still making a horrifically loud tap tap tap tap, not sure how long it takes for the hydraulic lash adjusters to pump up or if i should be running a thicker oil. Curious if this tap tap tap is just a side effect of regrind cams or not, anyone have any issues with hydraulic lash adjusters not pumping up fully after a rebuild?

 

click

 

Did you reset them?

 

reset them? no i took them out, cleaned them, and dunked them in a bucket of oil for a week or so, is there a procedure for resetting them?

 

Yeeeeee. I think the correct term is release. Not 100% on that though.

anywho....... you gotta stick a really tiny allen wrench in the hole and you'll find a little pocket inside (feeling around) and you gotta push it down. That way they'll go back to the correct height when they get earl pressure

 

gotcha.. like a dsm

How to replace lash adjusters/lifters | DSMtuners

 

took a vid this morning


I understand that ZZP sells taller lash adjusters with their stage 2 cams, are these just a revised version from GM like they sell on their website or are these specially made for their cams. I inquired about buying them separately from the cams.

 

so i pulled one of the lash adjusters today, it was completely frozen solid, no amount of probing through the top hole with an object could get it to budge, i wound up just putting it in a vice and you would be stunned out how much force was required to get the thing to start moving again. Im assuming now that they are all seized and that is the reason for the incredible noise under the valve cover. New ones will be here tomorrow so we will see how those perform when I replace the entire set.

 

so i took one of my 130k miles lash adjusters apart, heres what i found




seems that they are similar to the ford 5.4 3v design, fords also have a common problem with seizing, probably why GM also revised the internals of the lash adjuster in 2008 as well. Found this video of exactly what im experiencing in a ford.