Getting Ready to Start My First MJ

[StylerG]

Have an XJ, getting ready to buy an mj (actually a pair) 2.5 4x4. First thing is taking a good engine out of a 2wd and swapping it in. 4x4 has a solid body, but hasnt been driven for a few years. As far as the engine swap goes, id like to replace anything that would be preventative but not excessive (trying to keep tight budget here). Any ideas on what that would be.

My end goal is to have a very solid nice looking mj that is just a play truck, ill be putting my stock suspension from my 2000 xj on and buying some new leaf packs to give it a great ride, don't need a monster just a hunting truck....any help would be appreciated

Thanks

[Eagle]

4-bangers?

 

The rear main seal on the 2.5L engine is a one-piece seal that canNOT be replaced with the tranny in place, by simply dropping the oil pan (unlike the 4.0L). So it would be an excellent idea to replace the rear main seal while the engine is out and the back of the block is accessible.

[mjeff87]

Yay! another 2.5-er on the board! :cheers: Welcome.

 

X2 on the RMS. There's also a freeze plug back there above it you might want to inspect and replace if necessary.

 

You may or may not need an inverted torx socket (E12)for the top two bellhousing bolts. 4.0L's have them, but 2.5's seem to use regular hex head bolts. But, it's the same size you'll need for the starter bolts if they're original. If you come across any in either spot, go ahead and replace them with regular head bolts (or studs even).

 

Also, pay attention to the combination of bellhousing bolts/nuts as you take them out.....they are different lengths. Don't just toss them all in a box and trust that you'll remember where they're supposed to go back ;)

 

Jeff

[StylerG]

thanks, is the rear main seal something i can pick up at any auto parts stores? And yeah, 4 bangers, had one in a wrangler and for around town driving and already having a trail capable jeep i think i should be fine. What about vacuum lines, hoses, would the radiator still be good??? Anything else that would seem to be of concern?

[87manche]

you're likely to break most of the nylon vacuum lines pulling them. Get a roll of rubber hose at advance for about $20.

[mjeff87]

Yeah, it's a one piece deal. Think I got mine at Advance or Napa. The Haynes said specifically to not lube it before install, but that went against everything I know about seals....so I smeared some all purpose grease around the inside it first.

 

It ain't blown up yet, and it ain't leaking :D

 

Jeff

[StylerG]

thanks for the tips, I'm going to replace all the diff. fluids and transmission fluids too. Gas tank and fuel line wise should i be alright. I want to know everything up front so when i do the swap i don't spend two weeks figuring out what i should have done up front

[StylerG]

what kind of brake problems do the mj's have?

[KYMJ]

what kind of brake problems do the mj's have?

 

They're awful. Still trying to decide what I need to do to help mine.

[Pete M]

what kind of brake problems do the mj's have?

 

Aside from the fact that they are old?

-Rust can form in the lines that snake past the gas tank.

-The rear prop valves rarely work anymore.

-The Dana 35 drums are tiny.

 

Fixes include:

-eliminating the rear prop valve and swapping in a Cherokee prop valve up front.

-Swapping in a rear axle with better brakes.

-Swapping in a 95/96 Cherokee dual diaphram brake booster http://www.madxj.com/MADXJ/technical/technicalfiles/ARbrakeBoosterUpgrade/BrakeBoosterUpgrade.htm

[StylerG]

some more questions.....what sensors am i going to need to replace also any more gaskets....or once again anything that anyone else can think of, its been sitting for at least one year. Thanks guys

[Pete M]

I'd flush the radiator out. I'd also change the fuel filter after the first couple tanks (so the current one catches all the crap in the tank). But then again, filters are cheap, so maybe a new one now and a new one later would be best. :D Extra octane in the tank is good too to help out the stale gas.

[mjeff87]

some more questions.....what sensors am i going to need to replace also any more gaskets....or once again anything that anyone else can think of, its been sitting for at least one year. Thanks guys

 

There's really only a couple sensors on them that feed input to the ECU:

 

TPS (if bad, will run like poo)

CPS (if bad, won't run at all...carry a spare in your toolbox ;) )

O2 (can cause erratic, random poor running, hesitation)

MAP (same as TPS)

MAT (meh....)

[feerocknok]

Spin the alternator and make sure the bearing's not bad in it. Check your belts. My engine was so fubared, I don't know what's bad on normal 2.5s. Check your heater valve. I dunno what else.