My 2001 XK8 wouldn’t start when I cam out of work a couple of weeks ago, it had been fine in the morning but didn’t try to fire at all but it was spinning over ok.
I had it recovered and the garage just got round to looking at it, all basic checks were OK and no fault codes. They did a compression check on one bank and found two had 20psi and two had 0psi. They think it is most likely cam timing so I’m having it taken to a specialist.

if it is cam timing and the engines been spun over many times do I need to prepare myself for needing a new engine?

How much is a good second hand engine and fitting likely to cost?

The car has only done 64k miles with FSH and a receipt for the cam chain tensioner being done in the past.

 

Don't let anyone crank the engine until you check the cam timing. If you have a failure of something that caused the timing to jump one tooth the timing will be off but will still turn over. If the is an issure that caused it to jump a tooth by keep on cranking the engine there might be a chance it will jump another tooth. If it jumps another tooth the piston will hit the valves and you will need a new engine. You can take the cam covers off to see if the cam flats align. Turn engine by hand in clockwise direction only.

 

You need to pull that head off ..sounds like valves burnt to me

 

I haven't heard of valves burning on a car since I last resurfaced PowerPack heads. With VVT it should be a common occurrence, yet that has never shown up on anything I've ever owned. How long has it been widespread? 25 years?

 

Definitely not burned valves, that's ancient history. Either broken secondary chain or failed tensioner. They may have been changed, but are they metal or gen 2 plastic?

 

Have the Jaguar specialist remove the cam cover on the head with low compression and check the cam timing. If the secondary chain has jumped one or two teeth, the exhaust cam bearing caps can be removed and the cam reinstalled with the correct timing.

If the exhaust cam has jumped more than two teeth, the valves are likely bent requiring the head to be removed and refurbished.

 

What changed? No more tetraethyl lead? Better metallurgy? My project has $18k of receipts thru year 12, with 40k miles, yet only went 10k in the ensuing 12. It sounds great with only parking brake and a lean code I'm guessing is dirty intake. I'm going to do the old water de-carbon, fix the headlight change all filters and fluids and head to Salishan for 72 or so and find out if it's worth further investment or a quick flip. But, please, no valve on piston action. It looks so darn good it reminds me of many under the radar cars I had that I regretted selling, i.e., '55 300 Chrysler, TR-3, '66 Nova, '89 SEC, Datsun 2000, etc. But the XK8 nods to yesteryear, while being modern enough to justify a couple hours weekly on upkeep. Am I seeing the glass half full? I guess time will bring a verdict. But everyone I've talked to On this forum is genuine on wanting to help. I thank you all.

 

The engine has been turned over and the 0psi is a good sign the valves are already bent.

My question is should I be looking for another engine or can the heads be removed and rebuilt?

thanks

 

Ask a mechanic who can do the work but it should be able to be rebuilt. You will probably need a new piston and valves though.

 

It is also a sign that your engine is out of time. Before you start looking for a replacement engine do as I mentioned. If you have any mechanical skills, remove the cam covers and see if the flats on the cams align. It is simple to do and will show if you have an issue with the timing. If it the timing, have it timed and redo the compression test or do a leak down test. This will tell you if you have serious valve damage. Diagnose what is wrong with this engine before giving up on it.

 

+1 on removing cam covers and inspecting cam timing.

See post no. 6 above.