TJ Engine Replacement Project
- Thread starter wct097
- Start date
Had an hour to work on it tonight, so I got it onto the stand and hosed it down with degreaser. After that, I removed the water pump, thermostat housing, a couple of accessory brackets that were left on it, and the valve cover.
...and yes, I'm using a Dell Powedge 2650 server as a fluid catch tray. It didn't really do a great job of it, but the majority of the drippings and oil were channeled into the oil pans, so I'd call it a success.
The rockers were very dark in color, like baked on oil. No buildup to speak up, but you can tell they didn't use synthetic.
The TJ's rocker arms when I was checking them before diagnosing the rod issue looked pretty clean other than the oil that was due for a change. They were 'metal' colored for lack of a better term:
In comparison, the ZJ's rockers were almost black:
...and yes, I'm using a Dell Powedge 2650 server as a fluid catch tray. It didn't really do a great job of it, but the majority of the drippings and oil were channeled into the oil pans, so I'd call it a success.
The rockers were very dark in color, like baked on oil. No buildup to speak up, but you can tell they didn't use synthetic.
The TJ's rocker arms when I was checking them before diagnosing the rod issue looked pretty clean other than the oil that was due for a change. They were 'metal' colored for lack of a better term:
In comparison, the ZJ's rockers were almost black:
Best use of a Dell Power Edge server EVER 
LOL BajaCherokee.
LOL Imma finance my stroker kit.
HMAM?LOL Imma finance my stroker kit.
Best part about this project so far.
MadamAdam = the OG Deere1
The server is now in the trash can and the garage is cleaned up. Keeping the top cover from it for additional use. Have two more that I can task for additional jobs if needed, but they actually still run.Best part about this project so far.
My intention is to rebuild the old/original 4.0 and to use this one on a temporary (4-6 month basis) to get me through the winter with a 4wd, so I really wasn't thinking about pulling the head on this engine. What's involved with valve seals?
Pulling out the entire valve train pretty much. Not sure if you can replace the stem seals w/o pulling the head, but know it's possible on some motors.
Did that motor burn oil upon startup or while running? Are you going to pull the oil pan?
Didn't appear to be burning oil, but there was enough leaking around the valve cover and down between the intake and head to explain it, if it was. I didn't notice any obvious smoke, despite it sitting for ~9 months.
Going to drop the oil pan to replace the rear main seal and oil pan gasket. Would prefer it not to be leaking all over the place, even if it is a temporary solution. When the rebuilt engine goes back in, this engine will either be saved or saved & rebuilt as a spare for my mom's XJ which is at about 250k.
I'd check the bottom end rings for obvious wear or missing pieces as a minimum. That way you know what to expect when you button it back up and drop it in your TJ.
You can do it with the head on. They make an air hose adapter that screws into the spark plug threads. Pressurize one cylinder at a time with a good air compressor, remove the valve spring. Push the new seals on and re-assemble. Guess I should have said valve stem seals.
It's on the engine stand now, with the valve cover off. I hosed the entire thing down with de-greaser last night, and then cleaned up the valve cover mating surface with a rag and some carb cleaner. It's actually pretty clean now. I'm taking tomorrow off, so I'll probably wipe down the rest of the engine tonight and pull the oil pan so I can clean the gasket mating surface up. While the pan is off, I'm going to clean the oil pickup screen and inspect the bottom end.
Tomorrow I'll start by removing the crank pulley so that I can get the timing cover off. Then I'll replace the rear main, button everything back up with fresh gaskets, install the water pump, and replace the spark plugs.
Friday morning we'll be pulling the TJ's engine, swapping over the accessory brackets and flywheel, and putting it back in. We're using the shop to do the engine swap. It'll be nice to have the TJ on a lift. The plan is to take the wheels off so we can basically sit it on the ground to get maximum clearance when hoisting the new engine in. My preference would be to not have to pull the grill and a/c condenser.
I'll probably skip that for this engine. The old one will be getting a full valve job and machine work during the rebuild though.
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