Our '04 XJR has developed a knock and rattle from the right bank near cylinders 1 and 3, and I would be grateful for the input of knowledgeable S-Type owners. Here's the link to my thread in the X350 forum:

Knock & Rattle: Broken Valve Spring?

Thanks in advance for all advice and suggestions!

Cheers,

Don

 

oh , sorry to hear that !!
i think your right . it sounds like valve train. it doesn't sound hollow like a gudgeon or big end would sound .
it may be the shim/lash cap or bucket is sticking in the sleeve ,
if thats the case your cam lobe will be slapping it from a distance .
which would also sound this terrible , and could also result in the piston striking the valve as well . if that hasn't already happened .
you need to get that valve cover off for sure . it sounds like what ever it is it will stand out like a sore thumb when you expose it .
and maybe stick a bore skope in to see wether its worth engine replacement or tear down ! best of luck .