http://jeg.serverhouse.com/Jag_docs/Timingchain.pdf

Here you can find how to do the timing chain and tensioner replacement.

dssossg@aol.com

 

I've been reading everything that I could find on the web on this subject for a while now but haven't posted before. I wanted to replace the secondary tensioners and chains in my 1998 XJ8 (condition unknown) since I bought it with 115,000 miles. It now has 119,000 miles and runs great, but I was becoming more and more worried that a tensioner failure would cost me mega bucks. So I made two Cam hold down tools, bought a kit on Ebay containing the new metal secondary tensioners, secondary chains with links, and the necessary gaskets. I gathered up the tools that I would need, break cleaner for cleaning the gasket surfaces, permatex, wd-40, white out and everything else that I might need.
Without ever having the cam covers off, I had only pictures that were posted on the web to go by. I formulated a plan of removing the cam covers (after removing everything in the way of removing the cam covers) rotating the engine with a 24mm socket and ratchet, to install the cam hold downs, making marks with white out and then removing a secondary chain by grinding the studs from a link and seperating the chain and replacing the tensioner with the chain seperated. Because I didn't know how much room I would have, I wasn't sure of how I would replace the chain, but I was thinking that I might have to attach the new chain to the old one, remove the cam hold down tool, and thread the chain through by rotating the engine with the ratchet until the new chain was installed and the old one was out, then removing the old chain and connect both ends of the new one with the link that I used to connect the new chain to the old.
As it turned out, that plan sucks for more than one reason, but primarily because the the tensioner can't be removed even with the chain seperated. The The large sprocket for the primary chain is in the way. I realized this after I had seperated the old chain. I hadn't installed the cam hold downs because I had to decided to run the new chain through first since there is no room to install it any other way without removing something else. The exhaust cam sprocket is too close to the casting.
Well, now I found that the tensioner can't be replaced without removing something else either. I needed a new plan. Since I didn't have a tool for removing the cam sprocket, I drew inspiration from a post that I had read about removing the Exhaust cam, but the cam chain was seperated! I considered everything, and came to the conclusion that unless a very strong gremlin were to turn my engine with the 24mm socket and ratchet, I had nothing to worry about. The other three cams would stay in the proper position. And then I realized that it didn't matter whether they stayed in the proper position or not! I could always return them to the proper position. And with the exhaust cam lifted up a little, the seperated chain could easily be put around the cam sprochets and positioned properly even if the chain was off completely.
I could see that the exhaust cam sprocket only had to be raised a couple of inches to provide clearance, so I decided to do it without completely removing the cam. The cam must be raised pretty evenly for the first little bit or the cam will bind at the bearing clocest to the sprocket, I loosened the bearing caps evenly in stages. Then I removed bearing caps completely, put a rag around the cam where the last bearing makes contact, and installed the last bearing cap again very loosly (Just enough to capture the cam and keep it in the general vacinity). Now you can raise the sprocket end to where you need it, and use the last bearing and the tension of the valves (where the lobes are pointing downward) to hold it where you want it.
I then had both hands free to remove and replace the tensioner. Even though the chain was seperated, the cam didn't turn at all, and was in exactly the correct position when I put it down and tightened the bearing caps evenly. You can determine this because the flat spots on the cam (where you would put the cam hold down tool) were in perfect alignment.
With the knowledge of how to do this job (and this is what you need to know), I went to the other head and had the tensioner and chain replaced in anout 30 minutes. This is how it went.
The cam cover was already off. The flats on the cam were already aligned. White out marks were already matching one tooth on each cam sprocket to the link that was on it.
I loosened the Cam bearing caps evenly. I removed the caps. I wraped the last bearing area on the cam with a clean rag and loosly reinstalled the cap. I jammed a rag all around the sprocket and chains to catch anything that I might drop. I removed the 2 bolts holding the tensioner. I lifted the cam sprocket with one hand keeping a little tension on the chain and removed the old tensioner with the other, and placed the new tensioner where the old one came out. I placed the cam back down. The tensioner can't fall out because the large sprocket won't allow it. (If you aren't changing the secondary chains you are done except for bolting the tensioner and bearing caps after removing rags. Don't forget to remove the tensioner pin if there is one. You should torque the tensioner bolts to 124 inch pounds, the cam caps and cam covers should torque to 97 inch pounds. Reinstall everything else that you removed.)
If you are replacing secondary chains read on.

I seperated the chain between the white out marks (use any method that you like, but don't destroy the chain, you will need it as a refference). Lift the sprocket again and remove old chain. Stretch it out on a flat surface along side the new chain. Make white out marks on the links of the new chain that match the marks on the old chain. Making sure that the white out is on the correct side of the chain, feed it down next to the upper cam sprocket not the one that is unbolted. You will need to remove the rag for this. When it is fed far enough capture the beginning of the chain with a bent coat hanger, or some such tool. Continue feeding chain until you can place the marked link on the marked tooth of the upper sprocket. Make sure that it won't fall off the sprocket, but the sprocket can't turn unless the entire engine does. Lift the exhaust sprocket, and bring the captured end of the chain around it until the link with the white out mark can be placed on the marked tooth. Make sure to keep the chain on the sprocket (this sprocket can turn). Put camshaft down. Replace rag to catch droped items. Correctly install link and link clip in chain. Position camshaft. Bolt down tensioner to 124 inch pounds. Remove rags. Remove tensioner pin. Reinstall cam bearing caps and Torque to 97 inch pounds in stages evenly. Check for proper alignment of flats on Camshaft. When done with both sides Reinstall Cam covers and torque to 97. Use proper torque patern. Reinstall everything else you removed. Reconnect battery cable. Top off coolant.
The flats on the camshaft will tell you if anything is out of time. Make sure cams on both heads are correctly alligned at the same time. If they aren't, DON'T START YOUR CAR UNTIL YOU FIX IT!
This isn't a tricky job. It doesn't require any Jaguar tools. It isn't especially hard. It shouldn't be scary. It isn't even all that time consuming if you know what to do and you have some tools to speed it up like a 1/4 inch drive crank handle. Instead of spending any money on Jaguar tools that you won't use again, buy an inch pound torque wrench that reads fron 60 to 240 from Sears for under $60.00
As it turns out, this entire job for me wouldn't have been needed for some time. The removed tensioners were second generation with almost no wear and no cracks. The chains when compared to the new ones were less than 1/16 inch longer and looked new. It is apparent that the PO had the job done not many miles ago. I can only hope that he had the primaries replaced at the same time. I intend to proceed on that assumtion. However I will be listening for chain noise.
For me the job was fun, and now I will be able to drive the car without dread of impending total engine destruction. A bargain at half the price! Good luck.

 

Hello Atom,
I assume that your post was meant for me since mine was the first post in over 5 months. However, I don't get your point. Your post reads as if you have taken offense at something in my post. I say this for the following reasons: your title "Eh" your opening "Eh well" your statement "my thread from last year.. over 3,500 views" and referring to me as "Chief". I assure you, that no offense was intended.
As stated in the beginning of my post, "I've been reading everything that I could find on the web on this subject", and your thread was one of thoes that I read. Other than to view the pictures of your used parts, it held little interest for me since I was planning to do the work myself and was looking for advice and the experiences of people that had performed the job themselves.
The fact that, on my car, the job wasn't in need of being performed for some time , doesn't have any bearing on wheather anyone elses car is in need or not. As I stated at the end of my post "It is apparent that the PO had the job done not many miles ago."
I'm also confused that in your thread of last year (after the job was done) you wrote "My sheet is running silent as it should", and in your post of yesterday you wrote "I replaced both my primary/secondary chains guides/blades/ bs etc and it still rattles a bit at startup. Doesn't really knock but there is apparent rattling on first startup, never changed since i've had it."
You seem not to be worried at all by this on going rattle, but if I had someone else do the job for me and it still rattled every time that I started the car, I would be very worried indeed. Eh well, good luck.