When doing a hot adjustment on valve lash on my engine, I had an adjuster where the jam nut wouldn't turn. Seems the threads on the harder than the hinges to the gates of hell adjuster had started chipping off and had jammed the nut. It wouldn't turn even 1/6 turn with a hand screwdriver. Fortunately I have another rocker assembly I was able to rob an adjuster off and replaced the bad one. I ran into a couple of others that had the same issue back when I was assembling the engine and doing a cold valve lash adjustment. If I didn't have spares, I would have been dead in the water waiting for a replacement. Just something to look out for.
Here's a pic of the adjuster after I used a 1/4-inch impact driver to get the jam nut off.
Kevin 1951 Chevy 3100 work truck Follow this saga in Project Journal Photos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together.
