Hi, I just purchased a 1990 Cherokee XJ. I have wanted a Jeep since 1994 when my boss let me drive his old Wagoneer around his membership Ranch in Wyoming.

I finally bought one. My son's friend had one .. Body is in Good shape.. Sun burned.. but no rust. no major body damage. just the normal minor dings of use. Inside is in decent condition with the exception of a bad spot on the dash. Electric windows are stick but work.

Now the issues. I paid 1,000 for the truck. The truck needs the freeze plugs under the manifolds replaced. We are tossing around whether to just replace the engine. It starts and runs.. but has 270,000 miles. The engine appears to leak oil from somewhere (presence of oil residue). The manifold seems to have a crack as well.

I could buyt freeze plugs,, around 20.00, weld the header crack, manifold gasket 20.00.. a few hours of labor . and get on with life... <OR>

I can buy a long block from O Riellly for 1800.00. Add a new water pump, rebuild the injectors, replace the manifold.. then see if the trans needs work. (AHAHAHAH).. I figure with the engine replacement I will be in for about 2,200.00 or so.

I think a used engine is out... anything from that era has too many miles to swap (heard of a 850.00 90,000 mile engine but alas.. its still a 1990).

So ... give me your opinions.. what should I do? I can't drive it as it sits..

Plan is to have a trail runner.

The XJ is stock except for a 3" lift. Has very new all purpose tires (road really).

It will go into 4 hi.. but not 4 lo from my quick tests in the parking lot.

There is a vacuum device on the front axle that appears to need work.

-H

 

The issues you have don't seem like enough to write off the engine, too me. I also would not get an engine from an auto parts store, do the proper research to find a good company with a good warranty.
Also, if you're changing engines then there is the option of swapping in an HO 4.0. And lastly, I don't think welding the header will hold for too long. I believe they can be had for around $60 on Ebay.
Good luck and welcome to the forum!

 

"There is a vacuum device on the front axle that appears to need work."

What makes you think that? If that vacuum device is on the passenger side of the pumpkin, if it does not work you don't have 4 wheel drive. The vacuum device when working properly moves a "fork" that moves a "collar" in the axle tube that locks the 2 piece axle shaft together to give you 4WD. Without it locking, the axle applies power to the side that is spinning the most....which will be the shorter axle shaft as it is not locked, so neither front wheel gets power. AMHIK There are several fixes, the most rash being to replace the front differential, or you could replace the 2 piece axle shaft with a 1 piece, or you could lock the collar so that its always engaged (my remedy for now) or get the lines up to snuff so it works like it once did. It was a idea that did not work out as well as initially thought, I think. Note: The axle on the passenger side is WET in that the axle seal is at the hub end of the axle. When you open that vacuum plate on the axle you will have lube coming out!

 

is the oil in it old/used? I would get it analyzed, they can tell you how worn out your engine is. It's not uncommon for these engines to hit 300k+ miles without issue, if maintained. So get that figured out first before you make your decision.
https://www.blackstone-labs.com/

the vacuum disconnect is something you will want to get rid of. the one on my last jeep left me stranded more than once. You can upgrade your axle shafts and spend money on a kit:
https://amzn.to/38ci5nH

You can go to a junk yard and find a later XJ and steal it's passenger side axle, and get a block off plate of some kind.

You can modify the unit so it's always just locked.

You can swap it to a cabled operated system.
https://amzn.to/34ouGTF

How do you know it is going into 4hi, but not 4lo?

 

[QUOTE=aroundincircles;3629879]is the oil in it old/used? I would get it analyzed, they can tell you how worn out your engine is. It's not uncommon for these engines to hit 300k+ miles without issue, if maintained. So get that figured out first before you make your decision.
https://www.blackstone-labs.com/

the vacuum disconnect is something you will want to get rid of. the one on my last jeep left me stranded more than once. You can upgrade your axle shafts and spend money on a kit:
https://amzn.to/38ci5nH

You can go to a junk yard and find a later XJ and steal it's passenger side axle, and get a block off plate of some kind.

You can modify the unit so it's always just locked.

You can swap it to a cabled operated system.
https://amzn.to/34ouGTF

How do you know it is going into 4hi, but not 4lo?[/QUOTE

When I shift into 4hi the truck moves. 4lo it remains stationary.

Yes techincally.. I don't know if the front shafts are spinning.. What I know is if I put it in 2 in moves 4hi in moves 4lo it does not move.

-H

 

Thanks for the input!

 

So, why not just replace the entre front axle? It sounds like I could just grab a junk yard axle from something newer than a 95 and be good to go. Am I missing something?
-H

 

If the freeze plugs on the side are leaking, so is the one at the back of the engine......requires separating engine from trans to replace.
Welded exhaust manifolds work fine.
No need to flip out over replacing the front axle. There's a 20 minute fix that requires no parts.

 

Well of the options I gave above, upgrading the shafts gives you much stronger axle shafts, good if you plan on running bigger tires down the road, The option in the video of moving the shift fork over and locking it into place is relatively simple and cheap, the cable option I don't think is perfect, but it is an option. Getting just an axle shaft from the junk yard is also inexpensive. though requires more work on the axle you have.

A full axle is freaking heavy, not inexpensive, even at a junk yard, and not everybody can go pull one. My last XJ I upgraded my rear axle from a D35 to a C8.25, and I had to redo al the seals, bearings, etc. because the axle I got was not in as good of shape as I initially thought.

For the 4wd, that sounds like it's a shift linkage issue possibly. I would look at adjusting them:

 

Swapping the complete axle takes time, work and money!

The simple answer is that replacing the entire front axle is a lot more work then I wanted to do at the time. I have a 99 that the previous owner swapped the front axle for a older one with the vacuum assist 2 piece axle.
Problem was there was no vacuum applied to the axle, so there was no 4WD. The easy fix for me was to lock the collar "engaged" with a hose clamp and drive on. My 4WD works great, and I don't even notice the axle
being locked together all the time...it is like it would be in the factory installed axle on my XJ. I did pick up a HP Dana 30 at my local junkyard and have it in my garage as a backup or until I have the inclination/motivation to install it.

Cruiser54 may have another fix for the axle, so either way its not a hard fix for sure!

 

I am looking for the description on the axle lock fix. I saw one video that kind of talked about it. But I'd like a more complete explanation before I dive in. Can you direct me to what I need???

 

The way I went about it:

There are four bolts that connect the vacuum assist cover to the axle, remove those (remember it will release stinky oil) remove the cover.
You will see a brass colored "collar" and if you move the collar left and right you can see the ends of the axle shafts. Move the collar where
it locks the axles shafts together (more toward the driver's side) and secure a hose clamp around the axle on the passenger side so it can't disconnect again.
tighten the crap out of it. You will need to make a cover to replace the original to seal up the axle or you can disassemble the original and use it.
I will edit to add a link to a thread I posted pics in......

https://www.cherokeeforum.com/f2/99-...258873/index2/

In this thread, it just shows some pics of what is there. At first, I tried to use the fork and lock it over kind of like cruiser's thread referenced below. My way did not work and I decided to heck with it and just use a hose clamp.
So the hose clamp has been working for me for .........approx 3 months?? I don't think I have had it in 4WD but just for a few moments playing, but the clamp still holds even with the axle rotating all the time. I guess I should put a hose clamp in my tool bag

 

https://www.cherokeeforum.com/f51/fr...ss-91-a-38629/

 

Prescott... your close enough to drive up and help... hahaha.. just kidding. but .. if you want.. hahaha.. Maybe we will meet on a trail...

I am excited about getting this thing going. Unfortunately, I don't think I'm going to get it done this weekend. would love to . but alas.. My son says he is not going to have his garage available.. sadly..

But thanks for the help

1 question. what do I need to do about the vacuum hoses? I see the kits include some kind of electrical parts. Any idea why??

-H

 

CRUISER'S MOSTLY RENIX TIPS

RENIX VACUUM HARNESSES

NOVEMBER 17, 2015 SALAD 23 COMMENTS



The vacuum harness that attaches to the front of the valve cover and includes the grommet/fitting, and is called the front harness, is Napa part number BK 715-1367 or is a Dorman 46003.



The vacuum harness that is closest to the air cleaner, EGR etc, and is called the rear harness, is Napa part number BK 715-1366 or is a Dorman 46004.



The tube from the rear of the valve cover to the intake manifold is part number BK 715-1365 or Dorman 46005 and comes with the valve cover grommet.

The Throttle Body to MAP hose is no longer available. Click HERE to access a fix for that.