My XK8 Coupe was made in October of 1999. According to the dealer the engine number is supposed to be NL99092..... but I can't find it anywhere. I need to order a timing chain kit. The engine is clearly an AJ27 (easy enough to tell by the position of VVT solenoids).

I can't seem to find the engine number. There are a bunch of letters and numbers on the block "rib" where the later (2001+) engines are supposed to have it. like *222...222* which is not a valid number, and another "alphabet soup" mixture of letters that does not seem like a valid engine number either. I was unable to find an engine number in the front next to the thermostat housing either, which is where is expected be on my original engine that was made in September of 1999. The factory engine for my car had Nikasil bores, so it is possible that it got replaced at some point.

I see three different timing kits:

"Early" up to engine number 9810290000 - I am guessing that this is AJ26? Can somebody confirm this? I am almost certain this is NOT the one I want.
"Middle" from engine number 9810290001 to 0108122359. - this should fit my car it it has original engine. Because I was unable to find the engine I have no idea whether it will work.
"Late" from engine 0108122360 - are these 4.2 engines, or are there any late 4.0s in this number range? The valve covers on mine say 4.0, and it does look like a 4.0 to me.

The "Late" engines supposedly have different timing chain which looks like a "silent" chain as opposed to a conventional roller chain. Are the sprockets different? Other than taking the engine apart, is there a way to tell whether I have a "Middle" or a "Late" engine?

Has anybody here used an aftermarket kit sold by zedperformance.co.uk? They are allegedly German made, which worries me. I have replaced plenty of timing components on a BMW M62 engine, so I am not inclined to equate "made in Germany" with quality when it comes to timing chains, tensioners and guides.

 

When I looked into this for my 2001 4.0 car I found that there were three different versions of the tensioners made over the years. The second version came in at the end of 1998, the third version was introduced August 2001 on the last of the 4.0 cars. Those are probably the engine number changeover points you have listed - someone else may have better information.

If I were you I would take off one of the cam covers and have a look at what your car is fitted with, but it is almost certainly that middle range you have listed, unless someone has already upgraded the tensioners to the latest generation.

 

Juha_teuvonnen

Just curious as to why you would not consider using one of the after market kits available that come complete with tensioners, guides and chains. If you buy from the Dealer dont you have to purchase each part individually? Where did you source the cam locking tools and additional wrenches required to do the job. I plan to begin tearing down my engine in a couple of weeks on my 2000 XK8 Coupe. Keep us posted on your progress.

Thanks.

 

AJ26

Agree with dibbit that this is the one you want.

The 4.2 was introduced in June 2002, although late 4.0 litre motors also have the Morse 'silent running' primaries. See this post from Avos:
https://www.jaguarforums.com/forum/x...59/#post649836

The engine # should be visible at the top of the motor just to to the right (looking towards the rear of the car) of the base of the thermostat tower, although it can be difficult to see.

 

Found the engine number in the front, just needed to clean out the grime (q-tips and brake cleaner) from the part of the block that has it. it's NL99092... It's the original engine. I guess I need the kit for the "Middle" production. The dealer quoted something to the tune of two grand. I would appreciate reliable sources for parts kits, either UK or US. I often order parts from the UK, because even with shipping to the US it ends up being cheaper than buying them from US based vendors.

The tools are available dirt cheap on Amazon:

The reviewers complained about VVT setting tool (p/n 303-654) pins breaking off. I will look for a better quality version of that tool. XK's unlimited has one for $80. Worst case, can make it myself from tool steel. I have a lathe, a small milling machine and some welding equipment. The tool doesn't look like something that would be hard to make.

 

Check out Christophers Foreign Car Parts . Com. He sells a complete kit with chains, guides, tensioners and gaskets. Also, required tools.