Was fortunate to pick up a "Mechanics Special" 2000 XJR on Craigs list for $500 with suspected head gasket.
Owner said it started up and issued clouds of white smoke so he stopped and called his mechanic. The cost estimate of $3-5k put him off.

I got it home via trailer and inspected and found one cylinder full of water. Otherwise car looks pretty clean for 163k miles.
Prior to parting it I would dive in and check what I could find. It would be good experience to go with my other 2002 XJR.
Checking compression, showed most all cylinders were pretty even, even the one that had water in it.
I could not loosen 3 head bolts after they rounded off with my mistake on a weak 13mm tool so had to drill the top off and was able to do it without issue.

Now even though the car had done 163k miles, it had the original plastic tensioners. One secondary had lost its runner, but I found all the bits in the sump, The primaries were cracking and again, the bits were found in the sump. PO was lucky somewhere that they did not cause a bigger issue.

I did not want to do a full rebuild, and only wanted to spend what was necessary, so got a set of MLS 4.2 Land Rover gaskets that were cheaper than the Jaguar ones, as well as a set of updated head bolts with the better RIBE/Polydrive 12mm drive.

Key parts:

1. BOLTSx20: 4677857 ($3 ea)
2. Gasket Landrover: 4628399, 4628400 eBay ($99 set) (MLS)
3. Chains and tensioners: TK4162 Rockauto ($177)
4. Front cover seals

grr, found that the Victor Reinz set does not correctly fit the lower front cover seal. Had to get a Jaguar one here.

Now, I did not loosen the cam gears from the camshaft, and I know some purists will think I failed to correctly set the timing without the cam locking tools, but I reasoned, the chain is only one length and as long as I got the crank gears relationship correctly set, with a half tooth offset on each, and the +/- offset the correct way, the flats on the cams should each line up as long and as the crank position mark was aligned with the sensor, if the chain was the same length as originally manufactured, all would be good. So I set the crank position, assembled the heads on the car prior to the cam installation, added the crank gears, futzed 1-2 times to get the cam/chain alignment so that the flats would be aligned as I bolted the cams into position, kept tension on the tension side of the chain as I did the exhaust the same way.
Obviously, the 1st time I tried this, the flats were off just a little and one tooth of the chain either way was not right, but flipping the crank gears over, they aligned perfectly.

I completed the reassembly this past weekend, and after re-finding where all the vacuum lines went, and replacing some brittle Norma connectors it started right up on second crank and sounded fine, no errors at all. Now, 100 miles later, all OBD readiness checks have completed and full trims seem fine and no other ill effects and can still drive hard.

I did have TRAC and ABS unavailable alerts. so then removed the ABS control module and drilled two holes over the connector and was able to solder those isn and that cleared that error too.
Feeling positive for a good fix here.

I would like to understand the failure mode of how the fire ring gets compressed and crimped. My image looks like others that folk have shared.
Does water eat away the composite, then some compression pressure get in water and force out the ring weakened by the heat and then the compression pressure crimps the ring?
Thoughts?

 

theory:

2000 was a Dexcool year. 2000 was also a year that the composition
head gasket was used.

Dexcool is a known plasticiser.

The Dexcool turns the surrounding composition layer and other
related bits to mush. The fire rings then have no support or
weak support. The head bolts also are also not pulling down
as tightly on the gasket as the mush compresses or shifts.


... BHG.

opinion:

best preventative measure is to switch to the older Ford
yellow coolant, aka Zerex G-05 after multiple flushes to
remove Dexcool.


So are you still parting out the car?

 

Was that the silver one? I kept emailing him on CL, with no response. I was wanting to do the same thing you did.

Glad to see it went somewhere worthy and that you gave it new life.

 

It was silver, apparently I was the 1st to text and 2nd to visit and just took it. He thinks he may have priced it low as he was up to about 80 texts, and had to travel and get it moved from the office car park. Photo was not fully representative of it.

 

In my opinion, I have yet to use a Victor Reinz product with any success/long term reliability. Junk....

Only because the front cover seeps oil, I use a new gasket as well as put a small bead of silicone on the parimeter. It makes me feel better anyways.

So after you install MLS head gaskets, you no longer have to worry about the Dexcool being the problem.