Change water pump preemptively?

[paulo57509]

It wouldn't hurt to go ahead and replace it the pump.

I think this water pump is the original from the LS400 that had only accumulated 96k miles. I "think" because it had a steel/rubber bead gasket like the one supplied with the Aisin timing belt kit; OEM is typically sealed with FIPG.

The assumption is that it was +20 years old. No telling when it started to weep (a lot). Never did see any ground evidence.

 

[michaelluscher]

I'd suspect the OAP (alternator decoupler pulley) if so equipped before the water pump

 

[demarpaint]

If the pump is not leaking or making noise, I'd leave it alone. As mentioned they usually give fair warning, and with some of the garbage parts out there today there's a chance you might be installing a problem water pump.

 

[2strokeNorthstar]

You are assuming that drivers are attentive to their water pump weep holes, which includes 99.9995% of the non BITOG population.
Replace it proactively, and never experience the failure is the best case.

With part quality these days "never" is not a term I would use.