Water Pump Rotor Replacment Anyone?

Thermostat?

 

These water pumps don't give much warning before failing. Since you already removed it from the car, you should just buy a new one and be done with it. They are usually good for 150k miles or so.

Where is the coolant coming out of? Reservoir cap? Is it too full?

If you drain the coolant and there's chunks in there...maybe some additive was added to seal a leaking head gasket? That's a very common issue with these Turd gen cars when they get over 150k miles.

 

Before you waste good money on this, go buy yourself a new radiator cap first. See if the $10 cap will fix your problems

 

Don't know what's too hot, but I think 212F is upper limit of "normal". A fellow named chapman has a lot of good data on this in other PC threads. It appears like engine will shutdown around 221F.

For what its worth, Im just getting into the monitoring business with some new OBD gear. here are some rough computer readings on my 2010 (140k) and 2013 (65k). They are both behaving about the same right now, both with original water pumps. Am looking to proactively replace the 2010 pump soon, nevertheless. Portland, Oregon, 65-75F ambient air temp, running @ flat highway speeds, with no dramatic speed changes: The car runs about 195F. Seems like the computer works in gradations (or at least senses temp in steps of degrees), as its often "locked" at 195.8F. Saw it jump to 202 a few times - I think on a 85F day, when passing or accelerating. Around 60F, can go up a relatively steep grade (6-8%) and temp hovers around the 195F if I go 50-55mph. If I punch it a bit, it can hit the high 190's and barely break 200F for a few seconds, until I slow down. Based on my results, and your stress test data, I think you may have solved your overheat issue! hope this helps!

 

How many miles on it?
Have the EGR system and intake manifold been cleaned?
Is the coolant level stable in reservoir?

Where would you use that cap?

 

The various trigger points programmed into the ECM seem to be nice round numbers in Celsius, as you might expect for a car not designed in Liberia, Micronesia, or the US.

While warming up, if the heater is on, it seems to disable the supplemental electric elements as soon as the coolant reaches 35 ℃. If the car is warmed up and the engine is cycling (because you are Prius-camping, for example), it seems to cycle off at 50 ℃. The thermostat starts to lift a bit above 80 ℃, definitely opening by 85 ℃. It should be fully open (10 to 14 mm lift) by 95 ℃. The electric fans come on if coolant reaches 95 ℃ (other inputs, like A/C use, can also trigger the fans).

If the temperature reaches 105 ℃ and the ECM is reporting a water pump problem, it will abruptly shut down the engine at that point. (This comes as a bit of a surprise to the power management control ECU, which then logs its own code saying "weird, the engine won't start?".)

If the ECM is not aware of a water pump problem, then nothing special happens at 105 ℃, but the red thermometer light will come on at 120 ℃.

I drive with a ScanGauge always showing the coolant temp right above the steering column, and I pretty much never see it as high as 95 ℃, the fan-triggering temperature, except when I am parked and doing that deliberately, such as for burping the coolant. In normal driving, if I see above 90 ℃ I tend to notice, and if I see 95 ℃ I think about why. (Sometimes there's a ready explanation, like summer rush-hour traffic, or a big hill.)

 

Off-topic but interesting.

https://worldpopulationreview.com/country-rankings/countries-that-use-imperial

 

Still haven't heard of anyone replacing just the rotor/impeller. Sure would be a nice data point to collect.

 

I was going to do that, but, I can't find one now.
The used to be on ebay, but not any longer. I haven't check with Toyota to see if
it's possible to just get that... probably not....