I've got a 2001 XJ with 168k miles on it. It's in very good condition but needs routine maintenance and replacement of worn out parts. I'd like to get 250-300k out of it.

Recently, I changed the oil and sent a sample to Blackstone labs. It came back stating there are signs of antifreeze in the oil as well as elevated aluminum and iron that suggest wear of the pistons and cylinder walls.

It's in the shop now for other repairs (this is my winter car) and they haven't looked at the head yet but from all I've read on this forum it sounds like the head is cracked and will need replacement.

I understand that a head from earlier years will work but need some other work like replacing the exhaust manifold, etc. It may be too early to do this now but I'm getting ready for the eventual job of replacing the head.

I'll continue with more info after when they look at the head on Monday.

If anyone knows how to post a .pdf file, I'll post the Blackstone report

 

A replacement head is made to replace the OEM head that is stronger then the OEM head in all the places it needs to be so it won't crack like the OEM head .

 

Antifreeze is a hungry beast, and it likes to eat bearings.


Replacement from Clearwater that is correct for your year is an easier option.

 

Nope. Not too early. If you can confirm a cracked 0331 head, and you have any thoughts of not toasting your engine bearings, it has to replaced PRONTO.

As BlueRidge mention, the mixture of coolant with antifreeze wipes bearings in a very short time. And then you will see reduced oil pressure (how is yours?) and will have to sign up for overtime for the next 28 weekends to afford a replacement engine or a rebuild.

Have you been having to add coolant to the reservoir? This is the usual suspect when the 0331 head cracks.

Time is of the essence. Act now.

 

Thanks for the input. Tomorrow I'll see what the head looks like after we take off the valve cover. Hopefully there isn't much bearing or cylinder wall damage.

I looked at Clearwater and will have to call them for the right head. It's a 0331 head but will want to get one that fits with the least amount of modifications. I'm assuming the head is complete with valves, etc?

 

Okay, so I got the XJ back from the mechanic. He had lots of things to do like fix the A/C (replace the condenser), hook up the headlight harness (thanks Cruiser 54), replace linkage to the trans axle, etc. He took off the valve cover and didn't see a crack in the head. There is definitely antifreeze in the oil but didn't see anything. I trust this guy as he has been servicing my cars for the past 30 years.

I'll continue to change the oil every 3,000 miles and continue to look for problems.

 

Without wishing to sound like a smartass - how did the oil get antifreeze in it?

 

Just "looked" or looked while the system was under pressure?

 

there's already problems if there's antifreeze in the oil. Driving it more isn't going to help. In fact, it's goimg to get worse.

 

Brother - replace the head and don't drive it until you do.

You have several highly respected members on this forum telling you time is of the essence - you are asking for a ruined block by ignoring their advice.

If you have antifreeze in your oil now and do nothing you will continue to have it until you correct the issue. Your mechanic didn't see an issue, but you have one and you have the 0331 head - do the math.

 

x2 and do it before it kills the lower end .

 

It seems the consensus is unanimous and will heed everyone's advice. Will park it in the garage until we get a new head.

Any suggestions for best suppliers?

 

Recommended here most often:
https://www.cylinder-heads.com/

 

Thanks EZEARL. And I forgot to give credit where credit is due about the headlight harness and stock headlights. Thanks again.