Water pump failure?

What symptoms would i expect from a failed water pump on 300rdi disco?

Depends

Possible water leak from shaft,
squeeking / squeeling from bearing,
if impellor has rusted away/fallen off inside then overheating,

its a pretty simple lump.

what about a very loud clicking/tapping? no heat in the cab? rusty coolant?

never heard one clicking, whip the belt off and spin it by hand, maybe bearing failure.

rusty water - did it have antifreeze in it ??

ye, drained it when i bought it. put a 75-25 mix in because winter was on its way. noticed there was no heat on the drive to mot (11 miles) and no heat on way back. checked the coolant level. still full but murky. rusty coloured. done the mot failures. thought the sound was manifold gasket or injector related (past experience) but done everything but checked the water pump. but dont want to waste more time or money on fixing what isnt broke!

Rust/muck usually indicates a sludge build up somewhere, maybe an idea to flush it out sometime, that wont cause anoise though.

reckon the belt needs to come off so you can feel the bearings etc. maybe something stuck in the pump housing?