My '87 Van 2.1L Auto has been developing a new problem over the last
few months. It seems that when I've been driving for a while (a couple
of hours or more), oil starts to leak close to the clutch (and
seemingly *on* the clutch), causing it to start slipping and burning
the oil (causing lots of white smoke).

When the van has a change to cool down (say overnight, or a few hours)
the problem isn't there anymore (no oil leaking, no smoke, barely any
clutch slipping), until the engine is again warm and the problem
happens again.

I'm wondering if the oil pressure doesn't go up when the engine is
warm, causing it to leak where the main axle goes from clutch into the
engine.

Thoughts?

Thanks in advance!

Philippe