Rocker Shafts Won't Install
 

What should you do if a rocker shaft doesn't want to install into the camshaft housing?

9 of mine went in without much effort. 3 do not want to go in, even with some persuasion from a plastic hammer. I actually broke the edge of one of the shafts in the process of trying to tap it in. Never even got far enough to insert the rocker arm.

The bolt / nut were loose in the shaft. The cam housing was refurbished by a well know machine shop.

I assume sanding the opening or the rocker is a no go, or risk leaks. The only other thing I can think of is freezing the shafts?

They should slide in. Make damn are the bores do not have junk or corrosion. Sanding is okay, just use a fine sandpaper.

If the rocker shaft is cracked on the end from over tightening it will not go into the carrier.
Bruce

Start measuring to see where the problem is. It’s pretty much the same for every engine part. Don’t assume just because it’s new or refurbished that’s it’s correct.

Shaft ends are probably deformed, measure them.