I have a 1998 Vanden plas that has never had the timing chain upgrade - it only has 59,000 miles but I have a former volvo/jag land rover mechanic helping me at the moment - so to take advantage of his help I think I should do the all metal upgrade for timing kit and water pump (even though its low mileage and has no signs of needing it). Two different "jag guys" have told me "be careful what timing kit you buy -you need to get a good one" so other than getting a very expensive one from the jag dealer; what are some good non dealer kit options ?

 

Well, first off, you'll be in the neighborhood, so doing the water pump at the same time is a no brainer. My scenario was similar a few years ago, but more miles, the pump had no failing signs, but I replaced nonetheless. The issue with the tensioner kits is, most all are made in China, your speaking of a 20+ yr old vehicle, so OEM is scarce except from the dealer. Your mechanic would seem to have some insight on a purchase point. Though I did see one on Ebay that included a water pump, which was a surprise and the price has come down since my install. Don't forget to get new cam cover gaskets either.

 

I got the complete kit from Christopher's foreign car parts and was very pleased with the quality as well as the excellent customer service and technical support.

The kit contains everything you need for the timing/tensioner job.
https://christophersforeigncarparts.com/

You will also need a harmonic balancer/crankshaft holding/puller tool,
and a camshaft/crank timing tool set.

I bought my water pump from Welsh's
https://www.welshent.com/Jaguar-Water-Pump-P26109.aspx

It is recommended that you use a new harmonic balancer/crank bolt
https://www.welshent.com/Jaguar-Cran...pe-P26547.aspx

 

I hadn't been to this site in awhile, but they have OEM tensioners and chains... https://www.fcpeuro.com/Jaguar-parts...998&m=20&e=749

 

 

Ryan, they may of course have been replaced in the past, but they also may not have, and be well overdue for attention. There are 4 separate tensioners, two of which cannot be seen without removing the timing cover (or use of an endoscope) but the upper tensioners can be inspected by removing a valve cover, a fairly simple task. The early tensioners are plastic and brown/reddish in color, the later type are aluminum.

Sometimes an owner just replaces the upper, primary, tensioners, so an inspection of these doesn't necessarily mean that the lower, secondary tensioners have been done.

As the consequences of failure of the tensioners is so dire, it would be in your best interest to at least remove a valve cover and inspect the upper, primary tensioners.


If your upper tensioners are this reddish-brown color, they are the early type and should be replaced.



The later tensioners are aluminum and look like this.


.

 

Since the Ides of March are upon us, A Caveat Emptor about parts quality:

Having done a LOT of root cause into Triumph Stag timing chain failures, I discovered that parts quality is not limited to obscure old classics and in fact in today's market, DIY mechanics must pay particular attention to the quality and correct application of the parts they are using.

Case in point, I bought a cheap AJ27 timing chain set set online.

Upon receipt I looked at the old and new parts compared side-by-side (as I always do) with my knowledge of how the timing chain itself is oiled, and look what I found ...


Left - RED is cheap replacement set with no oiler for the chain through the tensioner and guide. GREEN is OE with an oil hole in the tensioner, a corresponding slot in the chain guide where the chain passes to oil the chain

So you might be saying, what is the big deal, the chain has plenty of oil in that area. Oh, does it REALLY? Have you been in there to check with the cam covers off?

I've been in there ... On Stags, we videoed a timing chain replacement with no oil hole and the chain remained bone dry during running, and on installations with the oil hole, the chain was slinging oil continuously.
The non-oiled chain often failed in less than 5k miles taking out all the valves.

Now it is possible in a VVT setup, there could by chance be additional oil coming off the VVT assembly and bush carriers that might by chance hit the chain, but just know that OE Jaguar AJ26/27 timing chain design in the engine is a tensioner with an oil hole and a corresponding slot in the timing chain guide so the chain remains oiled. So on a VVT, MAYBE you can get away with tensioners without chain oilers, but why chance it? No VVT, you absolutely should verify the chain has capability for continuous oiling.

So I tossed the cheap primary tensioners, bought OE tensioners with the oil holes, and cut matching slots in the guide for the tensioner oil hole to oil the chain.

Of course, not all roller chains are created equal either.
Make sure your timing chain has some manufacture mark or designation. Cheap chain has no manufacturer marking on the side plates.
.
There are other ways to check to see if a timing chain is of good quality, mostly look at the finish polish on the oval plates edges that ride over the guides. If those edges are not smooth they will eat the guides quickly just like a chain saw.
If the oval plates are smooth, that shows a quality of manufacture that takes an extra step in the manufacturing process to get those edges smooth.
Also measure the thickness of the oval plates to make sure they are at least as heavy a material as the OE chain.
take measurements to make sure the plates, pins and rollers are of OE sizes and thicknesses.
Also look at how the pins are pressed on each side. Quality chains have a uniform and clean chamfer on 2 areas of the pin tip to hold the plates in place.

Then take a look at the roller themselves. Rotate the roller between your fingers looking for a seam. If they have a seam, return the chains to the seller. Rollers should be made from a stock that was machined and its polish needs to be uniform and hardened because that is what takes the load on the sprockets.

Buyer beware ya'll, there are crap parts on the market for our cars, so do not take all the time and effort to same $100 on parts going into critical areas that if they fail, will destroy your engine.

Hope this helps.

Cheers!

 

Hi Guys I need so clarification. I am trying to figure out if my 2003 Jaguar XjR last 7 vin MF58608 came with the Metal Tensioners, Metal Guides with the Plastic Slides/Liners ? From what I've read a been told the earlier model 308's from 1998 to later 2001 model came with the Plastic Tensioners and was upgraded to the metal from 2002 and Beyond. Dispatch Date 04-July-2002 and Sold 28-Jan_2003. If so, What would It be the reason for replacing it. I would hate to buy parts I don't need. All Info and Advice would be Greatly Appreciated.
Thank You All

 

'03 had it figured out regarding tensioners. It was mid '02 they finally made the metal tensioner standard, so you should be good to go.

 

It would be well worth changing the water tower if yours isn't the metal one too? Sure most on here would recommend the same, while you're in there, the bolts for the tower are easily accessible. Not sure it helps, but I soaked the new chains with engine oil before reassembly.
Paul