Symptoms: White looking deposits from the dried OEM antifreeze, rattling noise from the pump shaft bearings going out, especially noticable at idle. When putting tension on the belt with my hand between pulleys, I could litteraly see the pulley on the water pump move. Otherwise, it is pretty hard to feel play in it with the belt tensioned up. If you want to see if there is play, take the belt off.

Mine only lasted 65K miles, but then my car is a 91. (72K miles now). It never failed to pump coolant, it was just making noise. After examining it after I removed it, I'm not sure if it would have seized, as the shaft didn't bind at all, it just leaked coolant around the shaft seals.

If you do decide to replace the pump, I suggest that you take the time to replace these too: All hoses at the radiator, the thermostat, the auto belt tensioner, the belt, possibly the tensioner dampener (judgement call here. I did it just to be on the safe side, although I couldn't tell if anything was wrong with the old one.) Tensioner adjustment rod (again a judgement call). Idler pulley (judgement call...my time is worth money...the part was only $30), Take a careful look at the fan bearing assembly. This part is not cheap, so I didn't replace it, but mine seemed fine. My fan clutch was not fine, but I fixed it by injecting new silicon oil in it (I don't remember the Toyota part number...search and you'll find the thread).

What I was really struggling with was weather or not to replace the radiator. Mine is the older kind without the metal sleeve reinforcement, and thus is prone to cracking at the neck. It is also at the age when many people have experiened a failure here. I opted to not replace it at this time. I'm planning on doing it this summer, before all the really hot weather.

There is one bolt on the water pump that I think was designed intentionally by sadists. You'll need a wobbly for your ratchet, wrapped in tape at the joint to keep it straight going in....

Good luck with it.

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