Ok, Thanks guys... I was just worried it would be a safety issue...

I'll sort it out.

Don't worry too much. The dust\grease caps dont have any form of seal or o-ring to seal in the grease (which can "bleed" when heated) and weep out the edge of the cap.

Get new caps and fit some form of gasket sealer to the edge when you fit it and it may help fix your problem. It may not fix your problem but it may reduce the effect.

well now it gets the wheel dirty. I would replace the grease cap to stop the leak.

yes wheel bearing grease gets somewhat liquid. Be sure you are using grease "for disc brakes" if your 1200 has disc brakes, it can handle the high temperatures that disc brakes generates.

I hope your'e right... It looked to me like the grease turn quite liquid?!?! I took two pics... one of my RHS wheel & the other of my LHS wheel...

You still think I shouldnt worry about it?

http://datsun1200.com/modules/myalbum/photo.php?lid=18133&full=1

http://datsun1200.com/modules/myalbum/photo.php?lid=18132&full=1

Replace the dust cover if it bothers you. Anyways this is a common problem, with any make of car. Nothing to worry about.

I was parked in town the other day - in the sun... when I got home I noticed the LHS (passenger side) wheel had grease splattered on it. On closer inspection, I noticed it was coming out of the dust cover over the wheel bearing! It worried me, but I jacked up the car and spun the wheel (I didnt have many tools on me & not much time so I didnt loosen anything) & all I heard was the disk pads on the disk... checked for shaking - there was none.

I spoke to an uncle who has worked on all his own cars and he said it sounds like the grease was old. I should clean it out, check for signs of bearing failure and replace with new bearing grease.
Thing is, I replaced both wheel bearings less than six months ago-although it was only the outer bearings. I also put the best quality bearings I could find - some german make. So I doubt the bearings could be worn by now?