Did Jaguar have a regular service interval for valve clearance (lash) check and adjustments in any versions of the I6 XK engine? Or was this typically done because of a problem or when other engine work was done?
I just reviewed the original “Passport To Service” for my 1984 XJ6 Vanden Plas and adjusting valve clearances is not mentioned for any of the Service Intervals through 105,000 miles.
BTW, after one burnt valve, a few leaky head gaskets, and some leaky cam shaft cover gaskets on my three running XK engine Jaguars, my gut feel is that checks should be done somewhere around every 60K miles because I have seen valves close up a bit after that. If 100K miles were driven without a check I would feel I am living on borrowed time. This is for a normal street not for racing.