Does that light noise sound like one of the chain tensioners is going? 2002 XK8, 90k miles.

Typically it is a rattle/clapping sound at start up then could go away. If it is from the fron of the motor I'd suggest to stop running it.

So, this comment is based on a discussion that I had with the Jaguar Dealership in Lynwood Washington. I took my title and was in search of some peace of mind, tensioner wise. My 99 XK8 has 106,000 miles, and runs beautifuly. The car was originally bought in Bellevue, and as of last February, I'm the third owner.
I asked specifically what to listen for from the tensioners and the guy told me, verbatim, "If youhear ANY rattling coming from the front of the engine, either side, that the tensioners were beginning to fail and need replaced. The rattling will be at start-up and when idling...at first. If not addressed, best case senario, the timing chain will jump one tooth and the car will run rough, worst case, the chain jumps two teeth and the result will be catastrophic failure of the engine due to valve/piston collision."

Advice-pull your valve covers and change the tensioners, because that machine gun you're hearing, will soon turn into a howitser...


They looked up all of the service records and told me that my kitty was very well cared for, and has no open recalls including tensioners (GIANT internal sigh of relief on my part.)

if the rattle/clattle/slapping at start up for a few seconds is not good, if it does it running at idle that is worse, if it is running like **** that is even worst. STOP starting it, sounds like the motor is ok still.

The 2002 should already have the SILENT RUNNING PRIMARY CHAIN and the later metal body tensioners along with the later style oil pump.

The chains/tensioners could still have a problem. Just because they are the newer style does not mean that they cannot fail.

Could be valve lash??
Could be 'piston slap'??
Could be a loose chain??
Could be a 'con-rod'??
Could be...............................

bob gauff

If your car was manufactured before September of '01 it came with the second generation tensioners which added an external spring to the oil pressure driven chain tensioner. My '02 did. This spring was added not to eliminate the potential for total engine destruction but to reduce the 'rattle' often reported before total engine destruction. Most likely to get total engine destruction past the warranty period.

Did you get the message?

DO NOT START THIS ENGINE AGAIN . . . NOT A SINGLE TIME.

Until you resolve the noise issue.

Thank you all so much. I only heard it AFTER I went for a 20 minute drive. It was sitting there idling when I first heard it, and thought about everything I've read on the forum thus far. It's going in for all new front bushings next week, so I'll have them pull the valve covers, which need new gaskets anyway. Yikes. What have been your experiences with parts and labor $$$ for both primary and secondary tensioners?

I had the chains, tensioners, belt and water pump replaced for around $ 2,000 by an indie Jag mechanic. What upped the bill a bit was also replacing the thermostat housing, thermostat and some hoses. Still, I considered it to be the best investment I've made with this car for no other reason than peace of mind.

Poppyboy,
Think about it this way. The engine use to be very quite and now this noise. If there is a noise, something is about to fail or has failed. Stop the engine. Get it fixed. What is the cost of a repair, vers. the cost of another (used) or new engine. A no brain'r.

Chuck
05/XK8 vert C.F. 1 of 200