hi forum...never having had to replace the water pumps in either of the 2 ford trucks ive owned, im not quite clear on the symptoms of one going bad.Heres whats happening. 93 F150 supercab, 302 , 117k miles.
Last night at intersection idling, loud screeching under hood (not the same type of "screeching" normally associated with bad belts/idlers etc(been there done that). dissappeared when accelerated, only happened twice on the several mile trip and 10 or 12 stops/intersections. This morning sitting at light, noticed steam type smoke vapor coming out from under hood on passenger side,nothing thick but yet a vapor anyway, stopped at store popped hood,couldnt see any steam. Looked over hoses etc trying to see if i had pinhole leak somewhere, couldnt see any, no dripping or puddles under truck either. Have noticed antifreeze resevoir empty for quite some time. I always fill it to "cold fill" level, usually within 2 weeks its empty again although looking thru filler cap of radiator level is near top.....im stumped,,,is my truck giving me indication that something "big" is about to go wrong? appreciate the advice!!

 

could be many things
suggest to have cooling system pressure tested.
which should find the leak
where ever it is,

 

Water pumps usually have a weep hole where coolant drips out when the seal is bad. If you look at yours and its wet and/or stained you'll have your answer. If that's not it, you should look elsewhere if coolant loss is your only problem.

 

naturally look for the obvious as a water pump leaking at the weep hole. if that is ok, then get a pressure test of the cooling system. that will find where the leak is. could also be a intake manifold leak or a head gasket.

 

It could also be a small leak in the radiator. Check the bottom of the radiator with a flashlight. Coolant will pool down there. A couple of doses of barrs leak fixed mine.