Rock shox rear shock help

[g60go]

Hey people,looking for a bit of help,I've got a rock shox bar shock on my bike,no idea of the age of it. Bought the bike last year,but it's a 96 San Andreas and this shock was fitted to it so could be years old! I can't really find much info on it! So anyway,I pumped it up last summer to use the bike as when I got the bike it was totally flat,and it lasted all summer. Then,I left the bike all winter without being ridden,and I've come to it the other week and it's totally flat again but when I pump it up it goes flat in almost no time. I have no idea if it can be rebuilt etc! Basically I'm looking for ideas! I've got a weeks holiday the week after next and plan to use it as much as possible but also want to use I throughout the summer now the weather is here.





There's this screw in one end too

 

[ishaw]

I'm no expert by any means in the area of air suspension, but it sounds like it has either a leaking air seal somewhere inside, or the valve could be leaking. Never tried this myself, and I'm sure someone more knowledgeable will advise, but I'd be tempted to pump it up and put it in a bowl of water to see where the air is leaking from.

A service should fix it, but I reckon for the cost of that, you might be better buying another shock.