Thanks Sheerwater & Beryl for your replies, I've flushed out & replenished the cooling system,sealed the corners of front screen,took out inlet at bottom of screen & checked for blockage - no problem ;seems to drain water away perfect.However, after a spell of rain I'm still getting water inside. Next time I get chance to look I'll check the fan seal as suggested by Sheerwater. Having something to go on, based on others similar experiences, does help. Thanks - Dave.