Outer Limits 4x4 Board

Question regarding my 91 75 Series Troopy.
I first noticed something was wrong when the rear end of my car started making clunking noises. It seemed OK on the straight, but turning it made a noise, and if felt like it was "Grabing and Releasing"
As I had taken the car for a "Swim" on several occasions, I already suspected i had water in the rear diff, so I pulled it out.
Yep, lots of water, only a little oil and it was thick, emulsified and generally yuk. No metal of any description in the oil. An encouraging sign. After a good clean down the diff looks in Perfect condition. There's not a mark on any of the gears, What I can see looks Brand New without the slightest hint of ware but I've not taken the clutch section apart. All I've done so far is take the crownwheel and center out (marking the adjusters so I can put it back in the same place) and split the Center Carrier in half. I've not removed the rest of the carrier from the Crownwheel at this stage.
I'd better say I know nothing of LSD's, except they use some sort of clutch arrangement to limit the slip in the gears in the center.

In short, I cant find a problem but I have not taken the carrier off the crownwheel yet so havnt looked at the clutch mecanism yet..

I have a theory. Can someone tell me if this makes sense.
I think that water has got in, is binding the clutches and effectively making it a locked up diff. Only when there is lots of force (ie turning) its finally releasing. Does this make sense?
If so, cleaning, reasenbleing and replacing it back with new oil should fix the problem. Right?
Any comments? Anyone else had this sort of problem in the past?

Thanks... Philip.

It makes sence lsd oil is fairly thick so water would change the characteristics of the oil. One of the blokes from work put 85/140 diff oil (what we put into the trucks at work and on a cold day is near the consistancy of honey) and he said it made the diff really tight. Just have a really good look around in there the gears could be smashed too jamming them up but iftheres no metal that would be unlikely. Now off to put some water in my diff.