Update: The adjusting screw with the nut backed off is very loose in the rocker; they can be wiggled side to side in the rocker arm. I suspect either the diameter of the adjusting screw and rocker arm don’t match or there is excessive wear. I can’t imagine the adjusting screw should be so sloppy when threaded into the arm. It is tricky to get the correct lash set; when locked down the adjuster moves up as the threads mesh/grab.

I have ECG rockers with adjusting screws and lock nuts, is there a torque value for tightening the lock nut? Seems like there is a potential for the nut to loosen while running the engine.

I found this post: Rocker adj nuts




.150 Stroked Y-Block:327.25 ci @ >1hp per ci
 

I have been using locking nuts like this for years.  I hand snug mine with a wrench and have never had one loosen in street driving. I suppose you could put a dab of Loctite Blue on them if necessary.

After first 20 min run valve lash was at .024-.026, seemed like the lash was pretty symmetrical and I don’t know what the builder set them at, I then set lash at .020 cold. After another half hour of running the lash hot/warm is at .026 and again pretty much all the same. The ISKY spec for the cam is .018/.018 hot. I don’t think a cam failure would be so symmetrical, I hope I’m right? I suspect the threaded adjusters or rocker arm threads, the adjusters are loose in the rocker, with the nut loosened, they can be wiggled side to side. Please advise.






.150 Stroked Y-Block:327.25 ci @ >1hp per ci
 

I’ve never had a problem with the locknuts coming loose. It you couldn’t move them with your fingers, I don’t think you do either.

Do a hot reset to the isky specs, and run it till hot. With everything being the same, I wouldn’t lose sleep over the cam until I checked it again. I’ve lost cams before, and they were all over, some fine, some more .050. Never the same and so little change. There’s a lot of parts there with clearances, assembly lube, etc. Maybe make sure the pushrod cups are correct for the adjustment screws. I’ve done that wrong, but they usually split.

miker
55 bird, 32 cabrio F code
Kent, WA
Tucson, AZ