one of the lads in local boat club (he is also the mechanic who fixes just about every outboard etc in morecambe bay) has drilled back of brake and fitted flushing tubes he got from the states. Fushes out with fresh water every trip and swears by it.
Someone else has reportedly drilled thru brake drum front where the spare hole is in wheel and flushes thru this (but I haven't actually seen it). Problem here on our local shingle and sand beaches is if tiny pebble gets in drum thru an unblanked hole its gonna cause shed loads of problems and could sieze the wheel.
Me - I have just had the drums off again and knocked the shale off and sprayed the WD40 carefully around the back plate etc. - But they will still sieze on if I dont keep moving the beast regularly.
Come on Keith - no such problems with a sib - at leat not a little one!