Hi guys-
I need help.
I am working on a very sick friend's jag. We cannot fix this and is undergoing radiation treatment. So while he is glowing in the dark, I'm trying to figure this out. ;op
This is a 1998 XJ8L.
Here is the history and what I done so far.

My friend mentioned his car was missing terribly (Running bad) and overheating. He drove it straight home, after chasing some punks who burglarized his house. He started looking online to see what he might find out. When he explained the symptoms to me, I immediately thought of a timing issue.
Before he got sick he checked all the igniters and they were operating fine.
After studying this a bit, I did the following to verify if the timing was bad:
Removed the igniters, valve covers, crank pulley and the front/main timing gear cover. I've carefully rotated the crankshaft through a few revolutions without any interference.
I checked the flat faces on the front of the cams on both sides. They all line up and are level with the mounting face of the valve covers.
I can find no indication of a timing mark on the crank pulley or timing chain cover.
Since both cams seem to be in alignment, I am looking at the crank to see if it is out of timing. Since each head has it's own timing chain and they are in alignment, I believe this to be very long odds.
However, I do want to verify that timing is indeed not the issue. I should state that I checked all the guides, both primary and secondary and they look to be in really good shape. No cracks or missing nylon anywhere.
I just can't see any indicators at the crank timing gears to give me any help there.

Any ideas?

Thanks in advance.
Cash Case, the not really a Jag mechanic, but not totally inept guy.

 

big cash:
You are probably right in that it would be unlikely for both sides to jump together. The crank timing is set by removing the Crank Position Sensor on he bell housing and installing a special steel plug that can only go into one of the timing slots on the flex plate ring.

Look under the "How To" Sticky at the top of the topics list for "Timing Chain DIY".

Now, as to running hot, these cars have a fairly good cooling system. What overheating symptoms do you have? I am thinking you might have a blown head gasket. If it is missing as bad as you say, it just about has to have a CEL. What codes do you read?
Good luck.

 

Done a compression test yet? if so what's the score?

Is there an engine warning light on? you can pull the codes with a basic hand held OBDII reader, this reports everything electronically controlled, i.e. coils (igniters) etc. Post back with pulled codes.

Sounds like an air leak or MAF if no physical timing off.

There isnt a factory timing mark, they're built from the bottom up, you have to rotate the engine to lock the starter ring gear, this brings the cam flats up to 'service position' (45degC AFTER TDC) Then the engine is safe to work on, i.e. pulling heads replacing timing equipment etc.

 

Sorry it's been a day or two since I've been able to get back to my computer.
I have not yet checked compression #s.
I do not know what codes the engine was throwing as I just started breaking things down.
Where on the bell housing is the crank position sensor located? And, is there a specific tool required to lock it down or can I improvise?
-Thanks
-Cash

 

@ Sarkenzap
I can't find the how to button at the top of the page.
Not sure if I really am stupid or it's hiding. ;op
-C

 

Big C:
If I knew what I was doing I would just give you a link, but I will try and explain instaed. This site has a number of areas called "Forums"
We are in the one called: "Jaguar Models > XJ ( X308 ) XJ8 / XJR"
In this forum are threads. We are now in : "1998 XJ8L behaving badly-"
Instead, go to the Topic: "XJ8 / XJR 'HOW TO' quick links"
then look for the how to for chains. Look around at the other "stickys".

The CKPS is located at the botton of the bell housing, toward the front. On the AJ26 engine, which the car you are working on should have, there is an access rubber boot beside the sensor, as i recall, that allows you to see an arrow on the ring to find the "special" hole in the flex plate ring. The CKPS is the only thing down there with a cable, and is held in with one TORX screw. After removing the screw, just carefully use a screwdriver to pry it out.

And yes, the tool that goes in there is a special tool availabkle from the online specialty Jaguar parts places. If you had a sample, you could make one, butI recommend getting the right one. If you were close by Atlanta, i would lend you mine.

The archives are full of how tos for changing the tensioners, which CAN involve timing the engine. You cannot use the so called "zip tie" method sinc ethat is the way to reoplace the tensioners without having to reset the timing.

Good luck and check back for more info.

 

I think I would have pulled some codes from the OBD system before tearing the engine down, but here you are.

Could be a bad coil or two along with a bad water pump or thermostat.

Get the codes and let us know what she is telling you.
Vector