What the title says. I'm not finding a draincock or plug, but maybe I'm looking in the wrong spot. At this age I'm guessing I would just cut the hose and replace with a new one.

 

Separate hose #7 from transmission cooler #2. Item #3 only on earlier jags.
Rgds
David

 

Don't forget the engine block drain plug. It's a royal pain to get to underneath the inlet manifold but it allows any sediment to drain from the block that's been reating there for years. I was surprised at how much was in there when I pulled it.

 

Item #10 or #11 Just behind oil dip stick on left side
Rgds
David

 

I was thinking more of the plug on the other side of the engine. The pic you have shows item 23 as the copper washer and the plug itself is partially shown.

 

C32276JAG PLUG, block heater XJ6 4.2 Liter

I think it is higher on the side of block, drain plug on left side is lower.
Rgds
David