Water pump noise went away?

Hey all, looking for a sanity check.

So my truck started making a noise recently, like a bad pulley bearing. Not screechy, more scratchy/whiny. Noise came on after startup when the fan spun back down from full speed to normal idle. As in, no noise while fan was ramped up, and then started when it slowed down. Proportional to RPM. Sometimes it was worse, sometimes not so bad. Figured it was either the fan clutch or water pump bearing going out so I ordered a pump and it’s on the way.

Had a Toyota tech friend take a listen, and he confirmed it sounds like the water pump

But yesterday I noticed the noise has gone away completely. No leakage that I can see from the water pump area, and reservoir level hasn’t dropped.

Should I be looking anywhere else?

 

Is the pump weep hole dry?

 

as far as I can tell, yes. But I also haven’t had a chance to really get in there and clean it up for a close look. Also haven’t seen any drips or lost any coolant per the reservoir level

 

Weep hole just shows pump bearing seal has failed as a warning the bearing won't be far behind. It won't cause measurable coolant loss.

 

Fair enough. Yeah I plan on changing the pump anyway since I ordered it. More so just confused by the noise going away completely

 

Pull the drive belt off and give all the pulleys and idlers a spin.
If they all sound “good” it was probably the water pump. As you can’t spin the pump by hand enough to tell. The only way to tell is by the “free play” or movement in the shaft.

 

Thanks everyone.

Think there's any chance it's the fan clutch? Being that it was silent at startup but started singing when the fan slowed down as the fan clutch opened up and started "slipping" (yes, i know it's a viscous fluid coupling, but there's gotta be a bearing in there that allows the speed difference). We didn't feel any play in the WP pulley, but the belt was still on so that's not ruled out. Again, more so just baffled that it "cured" itself magically. Bearing noises typically don't just get better without intervention. And puzzles like that poke a specific part of my brain that tends to plan for the worst lol.

At any rate, water pump just came in today so I'll change it sometime this week and report back

 

So it WAS the fan clutch!

Changed the pump, got it all back together and filled, and started it up. Noise came right back once the fan wound down. Noticed some subtle but significant play in the pink spool which we assumed was the failed water pump bearing at first.

Installed a new clutch, and (after it made a real scary noise due to the WP studs not being fully tightened to the pump side), she’s happily purring like a kitten again. Temps are down a tad as well, so she must also like the fresh coolant and hosed-down backside of the rad as well.