Just bought a '00 xj classic 4.0 auto. 4x4.
Had low oil pressure when I got it but didn't
Have misfire. Wasn't running rough at all.
Doesn't struggle to turn on either.
And check gauges wasn't on.. Did research
On 0331 head already. Replaced oil pump, and sending
unit already. Did oil change and started hearing
A clicking sound from valve cover. Removed valve cover, and
turned on jeep.
And noticed that the rocker arm on cyl.5 exhaust
Valve does not pump any oil at all its dry. Can that cause low
Pressure alone? Checked for crack between 3&4 cyl and didn't find anything.
Oil in valve cover looks new, not milky at all. Dip stick measures
normal level. Removed radiator cap while running looking for bubbles
and nothing once again. No smoke from tail pipe.
Ran engine with valve cover off expecting to see the
flow of water from crack and nothing. Any ideas of what it could
be? Am I doing something wrong?
-thanks

 

How low is low?

 

What brand of oil, weight, brand of filter?

What readings cold idle, hot idle, hot cruise?

Verified readings with mechanical gauge?

How many miles on vehicle?

Need more info.

Any unexplained loss of coolant over time?

 

It's around 15psi warm idle. 40 at start up. And 35 cruising.
10-40 castrol gtx oil, fram filter. Haven't had time to drive it at all
I'm working in Houston area right now so it's just been parked at home.
Flushed radiator as well. Radiator had rusty look to it.
Runs at 210 degrees. Engine doesn't shake or miss at all.
Just that ticking noise now. Not that loud however. That came after the
oil change.

 

First thing first. Get rid of the orange filter of death. Get a wix.
If a rocker is not getting any oil you have a sludge issue. Pluged up lifter. And its gonna gring thru soon.

 

Those numbers look good to me. Not sure you have an issue at all, unless someone disagrees with me.

Edit: Still want to look into the rocker issue. A lot of cherokees have a little lifter tick, so don't be surprised if it doesn't go away after resolving the rocker problem.

 

Befor changing to wix filter what should I do? Should I add an additive to oil
to try and unclog lifter? And re-do oil change? It's only 2weeks old.
Took to mechanic and he said he used mechanical gauge and that reading on dash
Was the same. I asked if he'd heard of the 0331 issue and said
that it was nothing with the head. That it would've been misfiring and smoking
Etc..... Should I just replace the head and see what happens from there?

 

You need to pull the lifter that is clogged. To do that You pull the head.

 

You will be bankrupt by next week if you throw parts at your xj this fast! Seems like your only issue is a dry rocker and you are taking about buying a new head! lol. With that said, I don't know how to fix that. Maybe check the lifter and go from there.

 

Idk how correct this is, but mechanic said 100% of the time
That there's a head crack in any vehicle, after oil has been drained
that its always gunna look like a cappuccino.
And mine was black....is this the way it is all
the time?

 

depends how long its been cracked and how big the crack is.

 

I'll be going home this Friday coming up. How difficult is it to pull the head to replace lifter? What's minimum oil pressure that it can have?
If I fill the water jug, and drive it and notice that it starts missing water without any noticeable leak, could it be the head then????

 

1. Take off the Fram filter and throw it as far as you can.

2. Put on Wix, Napa Gold, or Mopar. Refill with 10W-30, same brand as before, to bring it up to cold level. (40 is a little heavy for our Jeeps and not recommended). Don't drain the oil you just put in.

3. Bring your coolant up to cold level in reservoir and monitor.

4. Don't pull the head yet.

5. Don't use oil additives. Your engine does not need them.

6. Your oil pressure looks fine.

7. Driving your Jeep more may free up sticky and dry lifters.

 

since you did a coolant flush, the reservoir could be "emptying" because the rad itself was not a max capacity, if it was losing coolant at a very easily noticed rate, you'd have more than a slight tick

 

Thanks for the help!
I'll make sure I do all of the above...
I was just worried about all the 0331 reading I had
done. I was worried about the ticking sound
but now that I saw that the lifter on cyl. 5 doesn't flow oil
I can see that the lifter is the problem. Should I replace
All lifters? Where can I get them at?
Is it ok to drive like that... I'll try to post a vid on here
as soon as I can.
-thanks