What are these screws for?

[oldenoughtoknowbetter]

1981 R80 G/S leaking engine oil from around the two slot head screws on the left of the engine block. One's just below the oil pressure switch and the other faces towards the rear of the bike between the sump and the gearbox. The BMW parts fiche describes these as "blanking plugs" so maybe they don't fulfil any purpose other than to seal holes necessary in the casting process?
I have the same thing on 1990 GS but these are hex head screws.
Clymer/Haynes don't refer to these at all.
Therefore, can these simply (or not so simply due to access difficulties) be removed and resealed? Or do they fulfil some other vital function?
Many thanks.

 

[solidstate100]

I cant say I have ever noticed those before......anyway, if BMW call them blanking plugs they wont be doing anything other than blanking the end of the hole put there by casting (or more likely drilling of oilways) so presuming you can actually get to them and then get them out, they should be resealable......


Edit

Actually I have had an oil weep in that area for ages, going to go and check my G/S after I have finished my coffee........

 

[Rob Farmer]

They cap the oil passageways running through the block. If you can get the oil pressure tested as you may have a sticking oil pressure release valve.

 

[oldenoughtoknowbetter]

Thanks Rob. I have pressure meter with various adaptors to go into the oil pressure switch hole I assume? Is it unusual for these to leak? I've recently acquired and recommissioned the bike after very little use in recent times. From MOTs it has done only around 300 miles in the last six or seven years.

 

[Rob Farmer]

Richard Moore mentioned that the one on my PD's bottom end was jammed up and needed to be pulled apart and new parts fitted.

 

[oldenoughtoknowbetter]

Thanks Rob, the spring and the plunger are so cheap it'll probably make sense to change them anyway. I don't have a pressure gauge adapter to fit the 12mm thread of the oil switch so I'll assume the worst. New rear oil seal and oil pump O ring recently fitted but something under there is still seeping in addition to the screws. Excessive oil pressure would seem to make sense. Thanks again everyone,
Dave.