I recently purchased a 99 XJ 2wd for $250, 132k mi. I was told that it had a blown head gasket which made sense based on the symptoms. It would crank up and run(wouldn't idle), but it was blowing lots of white smoke, and the oil looked milky. I thought for the money I couldn't go wrong. Well after removing the head I discovered that the head was cracked (between cylinder 3 & 4). I decided to find the cheap used head from a salvage yard. After calling around I found a place that had a couple of them for $150. So I went and pick out the best looking one. It was a little rusted, but the valves were closed and it appeared to be in decent shape. After cleaning and installing it last night, the jeep won't crank. The engine turns over, but it sounds like the plugs aren't in it even when they are. I am going to compression test it tonight, but last night I removed the plugs out of a few of the cylinders and didn't feel any compression at all. Is it possible that all the valves are stuck open. I thought that would be highly unlikely, but not sure what else it could be. Before I put the valve cover on I made sure the all the rocker arms and push rods were moving as they should. Am I missing something? Any suggestions? I really don't want to take the head off again. Thanks

 

Hey, industrious AND brave. Like that. Have you pulled the valve cover to look for that down AND up thing with the valves? (I"ve got an idea for you if they are stuck down).

 

I did do that before I put the valve cover back on. It was the valves not seating properly. Last night I took off the valve cover, and loosened all of the rocker arm bolts enough to let the valves seat. After doing this the engine started without too much trouble. With the cover off and the engine running, I slowly started to tighten the bolts again. Sometimes the engine would die if I tighten a bolt too much at a time, but I would loosen it again and start it back up. Eventually, I was able to get the bolts torqued properly and it runs great now. I guess the corrosion needed to be burnt off before the valves would seat properly. As you could imagine, this was a very messy way of fixing it (oil everywhere), but it was much better than taking the head back off.

 

Hey fantastic! Hope it runs well for ya'. Adjusting hydraulic rockers on a Chevy you get that. With one out, you go in till it stops clacking, then as you go the final 3/4 turn it misses until the lifter bleeds down. (yes messy, and inside the old van )

A great trick if you need to push up on a valve; feed a length of small nylon cord into the spark plug hole, then turn the piston up with a wrench on the crank pulley. You also can hold'm up that way to change a stem seal.