Hello guys;

I'm spending the day installing my new tensioners. I'm doing the zip-tie method, and have the sprocket tied and all five cam bearings are removed.

The camshaft is not budging.

It appears to be holding on somewhere up front, near the sprocket. I don't understand how the thing could be holding on, and needless to say I'm being very careful and don't want to put too much muscle into anything.

Any advice would be GREATLY appreciated.

Thanks in advance.

 

Is the back end of the shaft partially lifted?

 

Ever so slightly. But the thing is so tight it's as if it's still bolted in. I don't get it. Really scratching my head on this one.

 

The tolerances are very tight, and it gets wedged. Replace the rear four caps, tightening them down a little at a time in sequence.

Then start loosening them again evenly, just a very little at time while pulling upward on the sides of the shaft around the cam that is under spring pressure. Keep the tightening/loosening movements small, or you risk breaking the shaft.

 

Hello White XKR-

Thanks very much for the quick response. I solved it just before I read your second post. I rotated the crank just a bit so the cam lobes nearest the sprocket were pushing against the valves. The lobes basically lifted the cam off.

Tight tolerances is right! I don't really understand how the thing could turn well with the engine running, if it can hold on that tightly without bolts.

Well, this was a well-timed project...tensioner is cracked from top to bottom, and part of the bottom shoe is missing. Lordy.

 

Just in time by the sound of it!

 

This might have been the next view that you would have seen if you would have waited a little longer:

 

Oh, that's a horrible scenario. And you're right...I was close.

You know, I bought this car back in early June from a Land Rover dealer...a local doctor had traded it in after 10 years of ownership. I managed to get in touch with the doctor before I made the purchase, and he mentioned (without me asking him) that the tensioners had been changed to the second generation several years ago, possibly before his ownership.

Well, based on what I've seen today, the originals were replaced with another set of first generation tensioners, or they were never replaced at all. But could the original tensioners have gone 111,000 miles without grenading the engine?

I just changed out one today, I'll do the other in the morning. Then I'll take a few snaps and post some pics. Bad stuff. Now I'm wondering about that piece of missing tensioner shoe...perhaps I should drop the pan and look for it? Could be long gone by now, but one never knows.

 

There is such a thing as second generation tensioners. They were not much better than the first generation tensioners. My car has the second generation tensioners and I will be replacing those over the winter with the third generation (metal) tensioners. Perhaps the previous owner was right.

 

It is my understanding that the second generation are just like the first with the addition of a spring assist to keep pressure on the chain when oil pressure is low. So, you could have 2nd gen in there.
Vector

 

It's not only the broken tensioner which is worrying.
the sludge which is built up is even more worrying, it looks like the oil has never been changed in this engine.
Even the cams on the camshafts are dark brown!

 

I think the general advice if that it's got down into the pan it's not going to do any more harm from there.

You're right but I don't suppose it matters now.

 

Agreed, This engine has obviously had very infrequent oil changes probably combined with short trips. No excuses for this poor level of maintenance on any car much less a Jaguar!

Fortunately, this is not my car, I just copied this picture from a article or previous post.

 

Heard that sound of chain on metal. limped home and that picture is exactly what I saw when I pulled off the left bank cam cover Tuesday. Hope to have it all back together tomorrow. New belt as well as PM.
For those doing the same fix, a piece of 1/4" luan 26 1/2" X 18" does a great job of protecting the radiator fins once the fan shroud is removed.

 

I had the guy I bought my last XJ8 from tell me he had the tensioners done, when I pulled the covers I could see they were Gen2 versions. I told the guy I sold it to and actually showed him pics so he knew what he was dealing with in the future.

I have yet to pull the covers off my XKR to check but.... I can see that the dipstick tube nut bracket was cut to remove it from the valve cover nut so hopefully this one has the metal ones installed, if not I will be doing this weekend project also.

Good luck on yours and can wait to hear the results.

 

Well done The Coupe just in time.
Thanks for the extra info every tip helps us all.

Cheers Al