99 Cherokee 4.0 154,000 miles.

I'm installing a reman engine in a couple weeks and I'd like to know what else I should replace while I have it torn down.

Kit comes with an oil pump and installation gaskets.

My list so far:

APN Header
Mopar water pump
Motor mounts
Oil filter adapter O rings
Distributor and cap
plugs and wires

 

Get a good look at your flex plate when you have it torn down. If you don't know about the problems with them just google it, they tend to come loose or crack.

 

If I had the engine out I would replace the crank sensor in the bell housing since I would have easy access. I would also think about the trans front main seal since you will have easy access to it as well. The engine rear main should be new with the rebuild so that's covered.


Also take a good look at the negative cable that goes from the fire wall to the back of the block. They can get really corroded and nasty and if you have it out then that might be a good time to replace it.


Look good at all the vacuum lines on the fire wall and inspect them for cracks.. The cracks are hard to identify sometime and cause check engine lights for evap codes. Run your hand gently down each one and inspect them and make sure no cracks.


Also just get in the engine compartment and really inspect everything and make sure nothing looks out of the ordinary on the unibody. Especially around the steering box. The body can have small cracks that will need welding to fix and with the engine out its a perfect time to weld and put in a reinforcement plate.


I guess I'll probably think of more when I'm laying in bed tonight.


lol

 

When I had my motor out I replaced the front brakes line that snakes along the firewall from side-to-side. It was rusted pretty bad. Got it from the dealer. I can see it would be a PITA to change with the motor installed.

 

If its easier to replace when its out do it.

 

Crankshaft position sensor (use Mopar original only)
Harmonic balancer
Thermostat - (I did a longblock install a few years back, and just to make sure I wouldn't get any grief for any warranty issues, I replaced the whole cooling system and kept receipts. A new radiator is only $89.)
Do not use metal intake-exhaust gaskets if your engine kit comes with them. Total crap and will whistle like hell after a couple years. Buy a $13 Fel-Pro and some copper spray and do it once.
Make sure your exhaust is working well. Don't risk a clogged muffler or cat on a new engine.
Change out the two top bellhousing bolts for ones with normal hex heads (good grief, the factory ones are a PITA)
Make sure all sensors and actuators are in good working order. At the very least, make sure your TPS and Idle Air Controller are working well.
I'd replace the torque converter if it's got more than about 70K miles on it.

Whatever you do, PRELUBE the engine before the first start by using a drill with a long standard bit to turn the oil pump. Video yourself doing this, and showing the oil coming up at the top of the motor (you'll need the valve cover off to show the oil pumping)

For warranty purposes, document the hell out of the entire install.

Pictures before, during, and after.
Receipts for EVERYTHING down to the oil and filter
Pics of the odometer reading, and something proving what date you were doing the install and start-up.
If you can, video the initial start-up/break-in procedure. This is usually 15-20 minutes. Get video of the initial start, the engine running, show the oil and temp gauges frequently, etc. Pay attention to get SOUNDS in the video, which is usually your first clue that something is wrong. Video the exhaust pipe to show clean exhaust. Basically, if the motor craters inside the warranty, you want to have as much backup and proof that things were done right as you can. Companies will often look for reason not to honor the warranty.
I used long zip ties to hold the throttle in place at the recommended 2000 rpm required for the break-in procedure.

Unless your provided instructions say otherwise, DO NOT use synthetic oil in a newly rebuilt motor. Use good old natural petroleum oil. I changed my oil and filter at 75 miles, 500 miles, 1500 miles, and then again at 4500 with natural oil. After that I switched to Castrol Syntec. I now have 4 years and about 60K miles on my new engine and it purrs like a kitten.

 

This had me wondering. Do the new rebuilt motors need a break in run to break in the lifters to the cam? Does the rebuild come with new lifters? If it does and they are flat tappet it would seem to me that it will need the break in run so the tappets run right.


Any one with knowledge on this for the 4.0?

 

Unpacking my titan reman and I notice this. They should have known better.

 

Maybe it's an "updated" 0331 head? as in a new casting? I would have to contact the company to find out if I was you. And find out if they already broke-in the motor or if you have to do it.

If you have to do it, agreed on only using conventional oil. I also buy a bottle of ZDDP zinc additive for the initial break-in.

When mine was out, I changed all the engine bay brake lines like CCKen said. Also did exhaust work, cleaned up some rust in the bay, change the track bar and/or steering stabilizer if you have to (with the engine out your staring at them). I also changed the seals in the steering gear box and the two hard lines coming out of it, super easy to access with nothing in the way.