[s-cars] Hydraulic Pump Leaking, now, what do these plugs do anyway?

[Rfeagleye at aol.com]

Rich, and all...

I had thought about the total plug/seal replacement, they sell a kit with all 
the plugs and seals... 

Now I wonder, what the heck are these plugs for anyway? Is it some sort of 
pressure overflow? Does the fact that the top "X" plug is leaking mean there is 
internal leaking/problems and that replacing the plug is really only a stop 
gap measure and it will be leaking again soon?

I did some searching on the subject and found lots of listers that had 
replaced just the "X" plug, so it looks like I can just do this and it will be OK, 
but I did find one discussion of the leaking meaning the pump was bad, and 
replacing the plug won't fix the real problem. 

Rob Eagleye
1993 S4