Just curious as to whether there is a consensus regarding replacement engines and trasmission for 1997-2002 series XJ/XK 8s. Any information on suppliers, costs, best options? Would appreciate any information or stories in this regard.


Clearwater, Florida

 

For a short question, you have inquired about a rather large variety of subjects. First point to consider is that 1997-1998 XK8 and XJ8 use a different engine and transmission than do 1999-2002(and '03 for XJ8)Model Year cars. This point does not have a significant effect on the cost of unit rebuilding between AJ26 and AJ27 versions, but is a factor when sourcing used unitsor in making sure what you have been sold is suitable.

Motorcars sells rebuilt engines, they are a site sponsor so are worthy of your first consideration. There is an outfit in Michigan who does likewise, but I don't knowmany owners who have opted for a $6K rebuild plus installation costs. You can likely have your transmission overhauled, or changed out with a rebuilt, fora totalticket in the $3,000.00 range. The only specific point on sourcing I can make is that I have read severalbad reportsabout oneof the transmission rebuilders selling on eBay.

These are pretty big numbers to me, and to the owners whose Jaguars I repair, particularly when weighed against the value of the car in the current market. I spend alot of time sourcing good used units and verify their mileage and condition. That usually means time and travel to minimize shipping and coreswaps, researching Carfax reports, etc. Sometimes it means purchasing and transporting a complete car, just to get a particular engine or trans with a documented history. Then I fully update and service an engine or transmission before I install it in one of my own cars, or before supplying it to anyone else.

For sake of example, last week I picked up a core engine in Chicago, 70K miles from an '01 XJ8.
This unit looks pristine, but itdropped an intake valve seat. It's a steel liner block, and I can build it up as either an AJ26 or 27...either way it will have new head gaskets, timing components, waterpump and thermostat, all other seals and gaskets renewed, and be good to go. That's a $3k engine, $4500.00 installed with new hoses, fluids, labor etc. and a one year warranty. I alsohave a Jaguar factory rebuilt AJ27, documented 50K miles, that I acquired in a wrecked '99XJ8. That engine is worth the same money.

So my own answers to your questions are centered around good used replacements,and inbeing very selective in what you buy. Alot of vendors are above the curve when it comes to pricing what they have: there are alot of used engines you can buy for alot more than $3K,andyou still have to factor in update and service costs before installationif you expect any assurance of reliability.Same is true for for usedtransmissions advertised at $2k, which still need a filter kit and 10 litres of pricey fluid. A bottom line like that makes it difficult to justify the expense, and a broken '98 or '99 XJ8 in otherwise very good condition is only worth $2K on a good day.

The worse day comes if you buy and install something of unknown quality, even if it does have a guarantee. One owner on JLbought a 2000 XK8 with a "fully rebuilt" engine, and had to change it out with a good usedunit soon after. There's a poster on this forum who recently had a used XJR engine installed for a huge amount of money, and still apparently has a huge amount of problems to resolve. One of my customers brought me a "20 K miles" engine from a major salvage yard to fit in his '99 XJ8, and ten seconds after I fired it up I knew that it had a jumped timing chain. So how many miles did the engine really have on it, and who loses the time and money to resolve those problems?

That's the long answer to your question... the short answer is "my way". I'm always interested in learning about better ways to find betteranswers, so we will both hopefully have additional comments to read on the subject.

Andrew Bernstein
British Auto Care
Powell, Ohio

 

I greatly appreciate your reply. Mine appears to be fine, but it now has 75K miles. I have read this forum (maybe too much) and even my own independent Jag shop seems to have lots of spokey ($$$) stories about 1997-2002 Jags with 4.0 liter engines. I like mine enough to keep it for a long time, but also had thoughts about replacing it with a 2003-2004 model if the opportunity came up, but the primary reason for the trade would only be my fears of a major (engine/transmission) disaster. My local independent Jag shop had a 1997 XK8 conv. that was beautiful, but I was told it was basically a total loss because of some engine computer malfunction that would have to be replaced at a cost of nearly 6K.

Regarding my 98 XJ8, I tried to get the previous owner's service records from The Collection in Miami, but never could. So, I have no idea as to the whether the timing chain issue was ever corrected. My mechanic says it would be basically silly and very expensive to tear it down to the extent that the tensioners could be inspected under these circumstances. He also states that 75K on a transmission for this make and model is about all you can expect. Basically, it seems like a wait and see situation that is not exactly comforting.

The Collection in Miami did state my particular car was in the shop about 6 times in the first three years of its life, but not much after that according to their information. They claimed not be be able to give me any specifics. So, I have no idea whether the major things that plague these cars have been addressed or not.

I do certainly enjoy the car, but always worry that a disaster could be around the proverbial corner. But, again, its is absolutely running great now and I have had it for just about one year and the last 12K miles only involved a power steering pump repair and some brake work.

So, thanks for the reply. If any others have addressed these situations, I would be pleased to hear those stories/experiences.

 

You're welcome, and I hope we read more from others.

I got the impression that your questions were proactive, and the answers you have gotten locally are opinions that I disagree with. Please ask your independant to provide you with the following:

1) An estimate for replacing the secondary timing chain tensioners
2) An estimate for replacing the transmission filter and replenishing the fluid
3) The phone number of the guy who owns the XK8 stuck in his shop, so I can buy it or fix it for him.

I posted info about the secondary tensioners on another thread today, compare that withthe estimate you get. That preventive maintenance, and the trans service, should cost you less than $1500. total. With that work completed, I would have confidence that the two most serious car-killing bullets have been dodged.

75K is early for a trans failure on average, and none of the units I have replaced had ever been serviced...sealed for life, indeed. And there have been many secondary tensioner failures with less mileage than that, some with catastrophic results. If you're not going to trade the car in the imminent future, find someone who knows exactly what we are talking about and have him service your car. There aren't any other systems or components on the car that I would consider as unreliable. Happy motoring!

One footnote, you didn't ask me about researching your records, but I'm an independant and have no more access than you do. I can sometimes beg them for my own stuff, and have to play Jaguar C.S.I. for the rest.

 

I'm afraid I actually have a question of my own, and not a reply. Would it work fine if I transfer my '99 XJR Supercharger & heads to a good regular V8 block ? I had a head job done less than 3 years ago and the engine has not overheated since but I have been losing coolant through the tailpipe lately, I am sure the heads are still great !

 

NO. SC pistons are lower compression. Your heads may be okay, but so may the block. It may be a blown gasket. Start with a compression check.