Where dose the air come from?

Looking at other posts it seems bleeding the breaks on landys in a hit and miss. I need to do my S3 88" every 3 weeks or so when the pedel hits the floor. My son thinks the bleeding ritual this is great but i dont. I clamped off the rear flexy hose and the pedel was fine, could this sugest a fault at the rear axel or just less volume for the master cylinder to cope with. For a very basic system its a pain in the arse.

Thanks in advance

Sounds like new rear Cylinders are required.

First thing I would do is to check the cylinders for leaks (not saying that just because you don't find a leak that the cylinders are not at fault of course). Could be other places where it is leaking, but that would be my firs point of call.

And don't buy Britpart cylinders IMHO.

thanks for your reply, I think the bit about clamping the rear flexy was a bit of a red herring, tried again and pedel went to the floor. however i have found the frount o/s cylinder is a little damp, the fluid level hasent been dropping.can air get in here?

Yes if fluid can escape then Air can be drawn in.

Aye air will get in much easers than hydraulic fluid gets out if there is a leak