I finally decided to tackle this project. I bought this Jeep knowing that it had an engine problem. Poor power, lots of smoke. OBD reader said misfire on cylinder #1. Ruled out all other posiblilities: turbo good, turbo hoses good, fuel injectors good, EGR good, timing good. So I ordered a set of rockers and lifters from Ebay (UK) and they arrived a few days later.
It took about 6 hours get the valve cover removed. Here is a picture:
I removed the rockers and found two of the exhaust rockers had their roller "jammed" down and not turning:
The other "good" exhaust rockers had excessive play in the rollers. The intake side was better. No problems and less play. There were also some exhaust lifters that came apart when I was removing them:
I compared the new lifters to the old lifters. The old ones are 1.35" tall and the new ones are 1.37" tall. The oil hole appears to be larger in the new ones and they have a slightly different design:
One exhaust valve (cylinder #1) was stuck closed. I was able to compress all the rest by hand but could not move this one. I tapped on it with a piece of wood and it stuck open. I tapped a little farther and it sprung back closed. I repeated this a few times and it seems to be working freely now.
Hopefully I can get it back together and test it tomorrow. I'll update this post later.