On the advice of many here I replaced the tensioners on my new to me 01 XKR. I was wondering if this was really worth it. After I got them off both of them were cracked. Maybe they go another hundred thousand miles like that ... or maybe they go another hundred.

Anyway I didn't want to wait to get the lockbar and spanner and after looking at it I was pretty sure I could do it without them. I just pulled the exhaust cams out of the bearings (left th sproket on) and moved the whole thing to get the tensioner out. I marked the chains, cams and sprokets so I could be sure the timing was correct then I zip tied the sproket to the chain and the input sprokect to the input chain to be double sure.

Overall it is probably quicker to use the tools if you have them as you don't have to retorque all the cam bearings but this worked and saved me the time (and expense) of waiting for the tools.

Here is a procedure I used if anyone is interested:

1. remove cam covers (and all that entails).

2. Rotate until flats on cams are up

3. wipe oil off sprokets, side of chains, flats and forward bearing caps then using a permanent marker mark the cam flats and the sides of the front bearing also mark a link on the chain and below its corresponding sproket tooth. The only thing that will move is the exhaust cam and we will have the chain sip tied to it but it is good to have it all marked anyway.

4. Zip tie the large input cam to the main input drive chain. Put the zip tie through the big hole and around the chain so the chain can not move on the sproket. This will ensure if the crank moves the intake cam stays timed properly. Note on an XK8 I don't think you can do this because of the VVT, you will have to either lock the crank or hope it doesn't move.

5. Zip tie the exhaust sproket to the exhaust chain in a similar fashion

6. remove the tensioner bolts

7. remove the exhaust cam bearing caps, note they must reinstall in the same location and direction. Remove this little by little a couple turns at a time untitl they are all loose. This will take a shile as the valve springs will push the cam up against the bearing caps.

8. lift cam off of head slide forward and slide out tensioner. Put in new tensioner finger tight.

9. Lightly oil cam journals and reinstall camshaft, tigten bearing caps slowly and in sequence. Once all are snug torque to 11 Nm. Then tighgten tensioner (I think this is 12 Nm).

10. If doing other side repeat 1-9.

11. cut off bundle ties, remove tensioner pins.

12. Rotate engine by hand until flats are on bottom, check torque on bearing caps (this shifts which caps are under the most pressure from valves). Rotating the engine will also pull any slack out of the side of the chains that is in tension.

13. Rotate engine by hand until flats are on top. All the witness marks you made in 3 shoud line up again.

14. Replace everything yu took off in 1.

 

Zip tie method worked for me too, been running for 9 months now and all good. Maybe update your method to include torquing the tensioner bolts up, you stopped at finger tight in your description.

When I did mine the plastic "slipper" had broken away on both tensioners, I dropped the sump pan off and removed all the broken bits that were in there. At the next oil change no more bits came out with the oil, so must have got them all.

Good write up, we'll done that man !

 

Nice catch ... I didn't forget to do that when I did it .... luckily

 

If you rotate the engine so that the Exhaust Valves are all closed, there will be no Valve Spring Tension to contend with. This position will be different than the "Flats Aligned" position.

Then, Zip Tie the Sprocket and remove the Exhaust Cam Bearing Caps.

This is on a per-side basis.