Ladies and gentleman of the forum,
This is my first post, but far from my first visit, after picking up a new to me 2001 XK8 Coupe. I bought it from a friend who, in all honesty, practically gave it to me. It's a beautiful car, but does need some overdue maintenance. I'm working though things, and trying to be sensible about what needs the most attention.
I'm sure for most (if not all) XK8 owners of this vintage, the timing chain tensioners are a paramount concern. The particular car I bought came with a thick folder of its service history that includes an engine replacement in late 2006.
My question is, before I go cracking open the valve covers, what is the likelihood that the new engine had the updated tensioners?
I'm sure that the most prudent if you will suggest that I had better just look, and I appreciate that. However, I do have a pretty good list of things to work on already, so I'm just wondering where to slate this in on it.
Thank you in advance for and help!
Bob
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Check the engine # first for year?

 

From a distance (and not having to get my hands dirty), it seems unwise to skip the hard work of taking a look. There were at least 3 generations of these tensioners, and, in terms of hard requirements, we enthusiasts say to replace with 3rd gen tensioners, but do normal/dealership shops do as well? Also, what was part of the engine replacement? Complete thing, just the block? Were the heads left alone? Too many variables in my view.

The idea is that these cars are not that expensive, and a failed tensioner can put you in an ugly situation of having to consider repairs worth more than the value of the car. Just my thoughts.

Good luck, keep us posted.

 

Gentlemen, thank for your replies. I thought that finding the engine build date was a very good idea. I tried calling the dealership that replaced the engine, but they only keep that info for 10 years. I will be doing some suspension work this weekend, so I will try to to sneak a peak at the date.

I'm happy you pull the valve covers and have a look, I just have plenty of other things to check off, and I'm trying to put them in sensible order. If I don't know about the tensioners, I think they'll have to be earlier than I was planning.

 

What a page turner mystery . . . your customer copy of the work schedule raises more questions than answers . . . broken studs, busted exhaust bolts, not to mention oil pump R&R for access to replace con rod! What happened? Perhaps a serious exhaust leak, damaged by a con rod exiting the engine block? Maybe your good friend only ever drove it on weekends . . . at Indy race meetings !!!

Enough of the poor attempts at humour. I commend you for going where you KNOW you have to go. This T/C tensioners issue is non negotiable. Ignore or postpone it and . . . poof . . . no engine and without its heart, no XK8.

Best wishes.

Ken

 

Ha! Yeah, I'm afraid I'll never know what happened. My friend was the third owner, and the replacement was done while the first owner still had it.

​​​​​So, I'm gonna do the shock mount this weekend because the noise is driving me crazy and I already have the part. Then timing chain check, then transmission service. Make sense?

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Good plan Bob, but I would emphasize an initial step which you may have done already . . . raid the stickies here on the forum and on Gus' brilliant website JagRepair.com and assemble all the workshop manual, owners manuals, wiring diagrams, TSBs and FAQ write-ups. That way, when you are working away at the the shock mounts, it is a simple task to know where to find the engine number or what steps are involved in opening up the camshaft covers.

You get 10 out of 10 in my book for having a well thought out plan. From your initial post, you speak of a list (perhaps a long list) of things to check or replace. I do similar; always have done. Well, not always . . . but first lessons from 50+ years ago proved there can be nothing more frustrating than shoehorning months of rebuilt engine back into an old Mk2, only to have a welch plug let go a month later . . . yes, the one at the back of the block just an inch forward of the firewall!!!

Final advice? Keep records as you work . . . record your list and your progress through it, receipts for all parts fitted, and phone pics of everything. All the evidence points to this documentation as the hallmark of a conscientious owner and a great car. These forums demonstrate the premium that buyers place on such. As a bonus, sharing such with fellow forum members here, will garner plenty of encouragement and helpful advice . . . and we love pictures!!!

Best wishes mate,

Ken

 

The secondary tensioners should appear as the one below.

Use a bore scope, or similar tool, to inspect the primary timing chain guide rails as they can crack and end up in the sump.

 

And we have our answer!

 

Yes, metal bodied secondaries.

I'm curious about the Morse primary chains - didn't think they arrived until the 4.2?

 

I see what you mean! Any guesses?

 

The August 13, 2001; engine S/N 0108130000 4.0 liter onward were supposed to have the metal body tensioners.

This includes the updated oil pump and silent running chains.

bob

 

But what about the guide rails? Were they improved, or should we expect to replace them on the 4.2L at some time?

 

The Chain Guide design is different when the silent running sprockets and chains are used as well as the newer style oil pump.

When I replace the timing components on engines UP TO ENGINE 0108122359, I use the original guides part numbers with the metal body (later) tensioners.

The later (narrow) chain guides are aluminum coated with a plastic and look very different from the wider (older) guides. I don't know if they deteriorate like the older ones.

bob