I came across a 1972 XJ6 about a year a and a half ago, hadn't run since 2005 or so, I've done some minor tinkering but about 3 weeks ago I put marvel mystery oil in the cylinders and let them sit, hoping to generally promote lubrication. Today I took that battery out of another one of my Jaguars and hooked it up via jumper cables and decided to see if I could get it to turn over. I took the plugs out and popped the key briefly into the start position and just got a metallic clunk, repeated twice and stopped. The lights and such worked so there was at least some current although the amp-meter was at the bottom of its range. I guess what I'm getting at is, is it probable that my engine is seized?
I suppose my next course of action would be to try and manually crank the engine?
I read that it's a 33mm, can anyone verify this?
Thank you in advance for any advice!

 

Seized engine, quite possible. Or the starter is kaput or isn't getting the amps it needs.....but, OTOH, the starter doesn't need much oooomph to crank and engine with the plugs removed

Yes, try turning it over by hand. No help on the wrench size, sorry

Cheers
DD

 

1 5/16" is the crankshaft nut size. A 33m may fit.