Hi

My 2001 XJR has done 126k easy driving miles. Last timing chain repalcement 60k

Is it necessary to change the chain again now?

What is a typical UK labour only cost?

Peter

 

Peter,

I would think you are probably OK, provided the job was done with the upgraded components. Is there any unusual valve train noise?
A mechanics stethoscope would be an easy first check. Inexpensive ones are available at most auto parts stores. If you are hearing tell-tale signs without a stethoscope... get one and place it on a cam cover bolt or two up front near the chains, and compare it to the sound toward the back. If you are more concerned, pulling a cam cover and inspecting the condition of the secondary slippers and if the replacement tensioners were metal bodied ones (which they likely are), could be a next step.

The cars do have chain driven cams.. albeit originally faulty, they should not require replacement like the duty cycle of belt driven cams.

Just my opinion, but I would start there.