VT XJ

I have a 2000 XJ that I bought for 1500 about 3 months ago. The previous owner said it had overheated, but not real bad. I got it to my house and basically replaced the cooling system, radiator, hoses, stat, waterpump. Does not overheat at all anymore.

Currently, it has low oil pressure(<10psi on the dash, sometimes drops to 0) after it warms up and loses coolant with none on the ground. I looked inside the oil cap and can see a bit of coolant where the typical crack on the 0331 cylinder head would be.

I'm pretty sure it has a cracked head, but if anyone has any more suggestions on how I can verify it, I have open ears.

My questions are:

If it's a cracked head and I've been driving on it(Lets say 20 15 mile trips), what are the chances I've done too much damage to the engine that replacing the head won't fix my problems?

Cost-wise, does it make sense to fix it? ANyone want to buy a fixer-upper in Virginia Beach?

With limited experience tearing apart engines, is head replacement something I should attempt myself? I am decently mechanical and have mainly done direct replacement of accessories(power steering, alt, starter, etc), suspension work, cooling system work, some axle maintenance.

Any recommendations for where to buy a cylinder head?

Thanks in advance.

Firestorm500

Based on your comments, I believe you will have to rebuild the whole engine.

The cracked head will not affect oil pressure. You bearings are gone.

Only you can decide if you want to pump about another $3,000 or so into having an engine rebuilt and replacing all the peripherals while you're there.

There's going to be some people who reply to this and say, "Oh no, you can build it yourself/have it done for cheap" but they will be wrong. I am being realistic.

tommyxj2000

i have the same problem with my jeep....but i cant tell if the head is cracked or not....should i find a 97-98 and swap all my parts out....have low oil pressure, looks like i've lost coolant but not sure because it bounces back and forth....where can i take my oil to get anialized to be sure and i have old oil laying around, can i use that or just do an oil change and use that....sorry for the hijack

1991Jeep_Man

x2 unfortunately.

I've heard even a modest overheating can cause that head to crack. And with coolant going into the oil, it eats up the bearings, probably causing your low oil pressure. You can either sink about $1500+ into a reman from Titan Engines and swap out the engine or look for another XJ. Sorry about the luck man, and after swapping all that stuff.

Firestorm500

A turnkey Jasper engine, 3 year warranty, will run about $3800 + accessories.

Ladies

$3800... Anyway to do this with a reman. engine under $2000? Or should I look for a new cherokee?..

DaddyCat

Before giving up on it, if it was mine, I would drop the oil pan and plastigauge the main and con-rod bearings. If they have greater clearance than allowable (.001-.0025 mains, .001 - .003 con-rods) you could replace bearings, oil pump and get a new head and spend less than a grand.
If the mains and con-rod bearings are within spec and the oil pump is good than the oil pressure may be lost at the cam bearings (not good).

Rmart30

the last 2 I have been around that just rods and mains were put in still had low oil pressure and it ended up being cam bearings finally solved all the pressure problems.
If it were me id do them all the first time. And there is no way id spend anywhere remotely close to $3800 on buying a rebuilt 4.0

1991Jeep_Man

Where is $3000 coming from? I've quoted from several different places, and Titan's has a reman 4.0 for my 91 for $1300ish, plus w/e shipping and core. They have a 7 year warranty IIRC. Jaspers is overrated and overly-expensive.

Gee oh Dee

The oil issue should be confirmed by mechanical gauge before signing the pressure off as low.

Any 4.0 motor after 97 is known to have sending unit issues, at least more common than earlier years. Make sure that isn't the real issue.

jth877

1996-1999 yard engine is direct swap >> $300-$400. Make brackets (real easy) for the coil on plug rail for the new 0630 head. You'll get a cheap solution that will be better than 2000-01 yard engine. If you need to, have your favorite mechinc pull/install the engines.

Buying a fully rebuilt 4.0 is a waste of $$$, there are plenty of yard engines around in excellent condition. You're problem is really not that bad... I would swap a rust free southern jeep with a bad engine any day for most of the rusty XJs up here.

tommyxj2000

on mine i changed the sending unit....still got low oil pressure

Cherockee

Another route is to just get a JY motor and drop it in and hope for the best- shouldn't run you more than a couple hundred bucks if you don't rebuild it, which i probably wouldn't on a $1500 vehicle. Very few will feel your jeep will be worth very much more than $4K even with a new/rebuilt motor, so it might not be worth the investment unless you plan on keeping it for a long time. The condition of the rest of the vehicle will determine if it's worth repairing.

The Rooster

i would just get a jy motor.... from a 98-99

VT XJ

Thanks for all the advice. I was afraid it was going to come to engine swapping or an involved rebuild/repair. I'll check out my options. There's a junk yard close that usually has a good stock of XJ's.