Engine noise

[longtrack 156]

My 2007 Yaris usually makes this noise until the engine is warm, any clues?
you have to wait a bit before the noise comes on in the video.

https://www.youtube.com/shorts/od1V63stgEQ

[Cletus Garfunkle]

I would pull the belt off real quick just to narrow it down. Maybe one of the bearings is finally trying to leave this world. You shouldn't need any big tools I believe just a 10mm, 12mm and 14mm IIRC to loosen the alternator a little and just push it back a little and take the belt off and just spin everything by hand (Water Pump, Alternator, AC Compressor) and see if any of it makes weird noises.

[longtrack 156]

I would pull the belt off real quick just to narrow it down. Maybe one of the bearings is finally trying to leave this world. You shouldn't need any big tools I believe just a 10mm, 12mm and 14mm IIRC to loosen the alternator a little and just push it back a little and take the belt off and just spin everything by hand (Water Pump, Alternator, AC Compressor) and see if any of it makes weird noises.

Thanks,
That was my next plan, just doesn't seem to be some thing in that area.

[mirageman]

I'd pull the belt and turn it on and listen for it to be certain it wasn't something internal. Often tough to determine by hand turning pulleys.

[mirageman]

I jinxed myself. I came here looking to find out what the heck my noise was, and I still can't remember posting here despite it being only 6 weeks ago. Identical noise in mine, like reverse in a manual transmission. Mine seems to go away after 10 miles of driving but returns when it cools off. I just pulled the belt and spun that water pump to find the same noise with just a jibbily jibbily spin with my index finger. No noise on startup without the belt. I'm wondering if 2 things I did contributed to this problem. 1) about a month ago, I drove in a long puddle in a parking lot. Car must've looked like a boat as I'm sure it was above the bottom door opening. 2) About the same time, I topped off my radiator/reservoir tank with 10+ year old universal coolant... the thing says for all colors, all makes and models and whatever. I'm wondering if I now have some oatmeal like caking at the bearings inside that waterpump that did it. Universal coolant manufacturers be damned!! Or... maybe at 275k miles or so, it's just time it went... I think I'll hold off on driving it until replaced. I don't want it to seize on the road.

[mirageman]

Well, I changed my waterpump, coolant looks very clean. I am quite certain I never changed it, either. No change in sound. It's my alternator, confirmed with a $2 mechanic's stethoscope. I should have done that first, but not complaining, as the original waterpump does have a sound when turned. I can't believe how those Japs left the frame like 2mm too close to the warerpump. Had to use a crowbar to push the engine over just a little bit to allow me to remove it and install the new one without scratching the mount. Metal gasket on the aisin pump. $44 plus shipping at rockauto. Will be testing my alternator at autozone tomorrow or so. From what I see on YouTube, this noise could be a diode and/or regulator or rectifier or whatever, not necessarily a bearing in there going bad. At 275,000+ miles, I think it might be best to just get a new one.