Hello,

I'm looking through ads on France's equivalent of craigslist and I found this 2000 XJ Sport with a 4.0 but a Low Oil pressure issue despite many changed parts.

The price is very good and if you guys tell me it's an easy fix then perhaps I'll go buy it!

Here is the original French:

"Jeep Cherokee 4 litres wild sport de 2000 avec problème moteur. Il y a un manque de pression d'huile malgré la pompe à huile neuve,les coussinet de vilebrequin et de bielle ont été changer ainsi que les 12 poussoirs. La culasse a être refaite à neuf."

So he says he replaced:
-Oil Pump
-Crankshaft bearings
-Rod bearings
-12 camshaft valves (?) not sure about the translation, to my understanding a "poussoir" is a piece that goes up and down and touches the camshaft directly...
-Cylinder head has been redone

He says he doesn't have the time to continue fixing it. He doesn't say anything about leaking oil so my guess is that the block is fine...

So from what I'm telling you, can you gearheads tell me if the fix is easy or is it going to be a PITA and a headache to get this XJ running again?

Many many thanks indeed!!!

 

Could be cam bearings are bad. That requires major work/disassembly.

 

Ask if he had to crankshaft ground when he did the rods/mains

 

How low is oil pressure? How many miles? Common problem with year 2000 4.0. Sometimes caused by a cracked head but sometimes they have low pressure for no apparent reason,even after a rebuild. Is it knocking?
I have been driving mine for a long time with only 4 PSI.

 

It can be a major repair or something as simple as the sending unit which nothing was mentioned about. If you can, I would verify the oil pressure with a mechanical pressure gauge. Just tell him that you want to verify it for your self. If it does have good pressure it can be a bad sending unit or just plugged up. Like I said the first thing to do is VERIFY for your self.

 

His 12 camshaft valves are probably the lifters.

I betcha he burned up all the bearings due to running with the 0331 cracked head. He did everything except the cam bearings. He would have had to disassemble the engine to get to them. He did everything above and below them, trying to cut corners instead of a complete rebuild.

I have never gotten good results only doing a job halfway. Therefore, I don't do things halfway. All or none.

There are better Jeeps out there. Let this one go unless you are prepared to rebuild the engine properly.

 

I would start with double checking oil pressure. 5 psi at idle is enough to keep an engine healthy. and 20 psi for normal driving. Not to sure about a bad pressure sensor. When I had mine go bad on my 2000 XJ the gauge was reading at max pressure.

I would double check pressure with secondary gauge. If it still reads low I would recommend to find something else, or plan for an overhaul.

 

It's a 2000 XJ with 105,000 miles. He states that it has to be taken on a trailer... (sounds like a bad sign?)

So the general consensus is that the low pressure is coming from:
-camshaft bearings which need replacement
-cracked head
-bad sensor

If I checked the pressure and ruled out the sensor problem couldn't I just replace the entire cylinder head? Would that fix the issue?? Wouldn't that also take care of both the bad bearings and a bad head?

There are XJs being sold just for parts too so perhaps I can get a sane cylinder head and swap them?


This plan gets more and more far fetched... I know. I'm just trying to understand...


Thanks for your input so far guys! :-)

 

Bad bearings are in the block. Cylinder head bolts to the block.

 

Wait, isn't the camshaft in the cylinder head? And we are talking about the camshaft bearings, right? I'm getting confused...

 

Not on a 4.0.

Click on this link....http://www.animatedengines.com/otto.html

 

If you cannot see and hear the engine running don't buy it. If it is running listen for noise, the 4.0 is noisy but you should not hear any loud dull knocking. Take off the oil fill cap and look inside for a milky substance which could be the sign of a cracked head. While your looking here start the engine and see if there is oil flowing across cylinder head...if oil is getting to top of engine it is getting everywhere else too regardless of oil pressure.

 

First, you haven't said how good of a deal it is... so it's really impossible to know if you should walk away from this. It also depends on your commitment to fixing it.
If this vehicle was described to me the way you have it would be safe to assume that it needs a new motor. Given that, if the rest of the vehicle is in great shape (nice paint, no rust, very clean interior), I had the means to replace the motor, and the purchas price was reflective of having to do all this work (say like $500-$800), then it would be something I would consider.
But if it is rusty/dirty/ugly, priced to high ($1000+), or I wasn't equipted to replace the motor, then this is something I would pass on.

While this motor might be repairable it will still require a large investment.

 

I see, everything you say does make sense...

There are no photos of the vehicle, I assume that for its age it's going to be fine, but yeah. There's a chance I could be wrong. Then again, it's hours from where I live so I can't just drive over there to check it out!

The seller is asking 2000€ for it. That's $2,500... What you could call a bit pricey...

This XJ is a limited edition model (1 of 200 sold) so it's kind of a collector's item. But I guess it is too much work... I found a cheap 98 RHD XJ (without registration) and I thought I could buy both and swap their motors... But I'm forgetting about this idea. I don't have the tools and space to store them! Plus I've never swapped a motor before and I'm sure I could find problems going from RHD to LHD.

So yeah, thanks for your input guys! Helped me quite a lot!! And I learned a thing or 2 about mechanics! ;-)

I'm stepping away from this XJ, I'm sure I'll find a better one later!