Thanks Fraser, I have been sidelined by weather, but will get those covers off ASAP and follow-up.

I was wondering about the bank 2 pressures myself. I have not yet located the engine number to confirm Nikasil, but wouldn't that just be the icing on this cake!

Stay tuned for more thrilling plot twists - your input is greatly appreciated.

 

While I am waiting to pull the cam covers I found this step by step with pics on changing the timing chain, tensioners, and related steps. This is a '98, but looks like the same setup as my '01.

http://jeg.serverhouse.com/Jag_docs/Timingchain.pdf

Wow. Looks like fun, and I am half-serious.

 

Changing the upper tensioners is, indeed, easy and you get to brag that you did it yourself. The tool kit is available from several sources at a pretty low cost. The tensioners are rather cheap if you buy the Lincoln LS part numbers. Same engine.

Never having done it I spent only 4 hours and detailed the engine as I went.

 

I pulled the cam cover on bank 1 this evening and here is a link to what I found:

http://www.dropbox.com/gallery/59922...Bank1?h=ae0619

You can see that there is a piece of the secondary chain tensioner wedged between the sprocket and the head and the secondary chain is broken. Other than that this side looks really good, no visible damage anyway. I will need to loosen the cam to get the piece out. There is also a pic of the tensioner after removal; the side guide is broken off at the bottom. The tensioner itself looks very good otherwise, with no cracking or pitting. It will be replaced of course.

This explains the zero compression in one cylinder. Looking forward to getting the other side off tomorrow.

 

ps) I realize now, having gotten a look at a whole secondary tensioner, that the wedged piece is probably NOT a piece of it, rather a chunk of some other guide part from farther down.

This is disappointing to realize, as I was hopeful it could all be repaired from above.

Sigh.

 

But repairing the primary tensioners is fully documented and just part of the broad scope of entertainment provided by the Jaguar. If you had wanted transportation you would have bought a Honda.

The complete tool kit to replace the primary tensioners is also readily available. PM me for more info.

Incidentally, After 9 years and 32k miles I had a part failure on the Honda Goldwing. Had to replace the hand brake micro switch that controlled the brake lights and the cruise control. Cost $13.25. Bet a Jaguar micro switch would have cost considerably more.

 

Looking at your photos, it never ceases to amaze me how clean these engines are after so many miles. I had my covers off recently, and it looked like it was still new. Sorry to hear about your troubles, I hope it goes well.

 

We often tell people to check for the little things on a no start situations keeping in the back of our minds that this is a real problem and it could be the cause this time. Sorry you are the victim this time! If you think it is doom and gloom I would love to see and hear you when you get it up and running. It is worth the effort. It is truly a great car!

 

Can't express how grateful I am for all the counseling here on the forum - Gus, Test Point, Super Sport, and everybody else who has posted helpful information.

I do love this car and will get fully into this repair! Ironically Test Point, I am driving a Honda while this project is underway - my older son and wife moved to Taiwan and left their cars with me the day after this happened!

Thanks again - I will update along the way. Only my wallet will suffer!

 

Oh dear, Oh dear !

Don't a few pictures do better than a thousand words. I would say it is time to take the heads off and check the valves, and piston tops. If its just a bent valve, no problem, just put new ones in. You can then do ALL the tensioners and chain slippers and have almost a rebuilt engine. You can also check the Nikasil linings.

 

As appealing as the whole tear it down and replace all guides and tensioners might be...

What I have found for certain is I have a broken right secondary chain (all pieces are accounted for), and a broken right secondary chain tensioner (the wedged piece was the bottom part of the tensioner; all pieces accounted for).

Left side looks fine. My question is this: before I start tearing the entire timing system down, would it make sense to replace the broken secondary chain and both tensioners at this point ONLY and put it back together and see where things stand?

Has anyone ever changed a secondary chain without first pulling the primary chain entirely?

 

There is a process to replace the secondary chain without pulling the front of the engine apart. Accomplished by zip tying the primary chain to the intake sprocket and then removing the cam and installing the chain from the rear.

I cannot remember if this can be done on an XK8 with the VVT assembly on the front of the cam or only on the XKR, which doesn't have the VVT. But then I don't remember which you have anyway.

If you go that way be sure to keep the cam caps in order, front to back and up to down and tighten them in stages and staggered.

Since replacing the secondary tensioner on the other side is easy at this point I might invest the $65 on wishful thinking and faith alone.

Good luck! We all wish you well.

 

These results surely tell all: -

Bank 1 obviously OK until the tensioner let go thus bending a valve.

Bank 2 is clearly in trouble, in fact it looks like before the cam tensioner let loose you had a 4 cylinder engine with a small assist motor attached. Even if the main camchains are left alone, I would certainly lift off both heads for an examination. If the Nikasil is OK, nothing lost and much gained because you will then have good pressure on both banks, (assuming you do a valve replace/grind-in job on both heads), and restored performance.

Being optimistic, I can't see just one bank suffering Nikasilitis and not the other, but I may be wrong.

 

The pressure readings are obviously out of limits of reason on both sides. The high side is way too high, should be about 155 - 160, no oil, throttle open. The '0' was probably with a valve depressed and since the cam was not turning all the pressure went out the open valve. The other side way too low, as in dry cylinder walls. Fix what is obviously broken and lets see what happens. It ran fine up until the chain broke.

 

Thanks for weighing in guys. I do not have a Nikasil engine, by the way. I am well into the steel liners at F23392 in the VIN.

I do think the compression readings could be misleading in this FUBAR situation and would like to read them again after replacing the secondary chains and tensioners. Not with fuel and ignition, but getting the oil pressure up and seeing where I'm at before pulling the heads and going the whole 9 yards.

It did run really good before I turned the key that day...

 

Fingers crossed and hope for the best!

 

Careful about the VIN and Nikasil. There is no documented correlation between the VIN and the engine serial number. The first steel sleeved engine serial number was 0008181043. Any dealer can look up your engine serial number from the VIN. Look at your assembly date on the driver 'B' pillar. The serial number above represents an 'engine' built August 18, 2000 at 10:43.

My '02 was supposed to have the metal tensioners but was assembled in June '01 before the August conversion. Plastic it was.

 

Good advice Test. I called the dealer and was told the date for my VIN is Sept 5, 2000.
I will redouble my efforts to find that engine stamp to be certain...

I found a guy on Ebay that will rent the tools for the cam work for $75 for three weeks, which seems reasonable. He wants a $425 deposit however. Anyone know of a better way to connect with a tool set?

 

Why not just buy them, then sell them on? Annie Jenkins at the Jaguar Enthusiasts Club will sell you the original new in boxes Churchill service tools. I've no doubt you will get your money back selling them on, as this job is very common!

https://vault2.secured-url.com/jec-d...py_of_asd.html

 

Are these the tensioners I should be buying:
http://www.dropbox.com/gallery/59922...oners?h=2a511f

Is there a 100% metal version or are these what is referred to as the metal version? These are "OES Genuine."

Thanks, I want to buy the best parts.