I bought my 91' Jeep Sahara about 4 years ago and, unfortunately, the previous owners didn't take very good care of it. I had to rebuild the transmission in 09, followed by replacing the transfer case (which I got off of an XJ) and I knew it was only a matter of time before I had to rebuild the engine. This is a log of my engine rebuild effort.
To begin I had to remove the Transmission. I know most people say you don't have to, but it will make installing the engine a hell of a lot easier.
It's clear this engine has seen better days. I was getting a knocking sound coming from the rear of the engine. On top of that I was getting a lot of drive line vibrations, even after replacing the U-joints. I suspected the motor mounts.
I took the fan and radiator out and unhooked everything from the chassis. The only thing you really need to mark is the injector connections near the back of the engine. Everything can only go back into one place. It is a good idea to take a picture of all of the wire connections and all of the intake manifold connections before you take them apart!
next pull it out
Sure enough, as i suspected, a busted motor mount!
After taking pictures, I took everything off of the engine. It was leaking oil from just about everywhere. Look at the build up of gunk all over. SMH
I then took off the valve cover and oil pan. It's unbelievable how gunked up the head was.
After taking the head off, I took out all the pistons and the crankshaft. It was a task knocking out a couple of those pistons. My cylinder walls were so worn down, it made a lip towards the top of the cylinder.
The head and pistons. My goodness they are in bad shape.
I took the block to the shop. Gary Didell helped me with the machine work. He bored it and honed it for me. Notice the ring around the top of the cylinders. The piston rings had worn deep groove into the walls. We had to bore it .060 over, and even had to sleeve the first cylinder.