water pump cleaning?

Just wondering what the best method of cleaning water pumps would be? When I got the 'van it had a new one in the sink, so we're using that no problems. Today, for no reason it stopped working, not sure why, if it jammed or what. But the light stayed on in the control box to say it was on, but it wasn't, so we turned it off, I went to check water level which was fine, we turned it back on and it was working again fine.

My other half suggested we get another as a spare just incase. Fine i thought, good idea. But they're pretty expensive, now there are TWO of them in a bag of bits in the front of the caravan, pretty grotty looking bag of bits which include some bits of waste pipe, so i'd want to give them a good clean first! What would be the best? I was thinking of soaking them in dis-infectant for a while, then run some water though em when next onsite?

Any tips or suggestions?

Thanks