Pool pump keeps shutting off. Replaced pump, still happening...

[Dagobah]

As the title says, our pump keeps randomly shutting off. Trying to track this down and could use some suggestions.

All started a few weeks ago. Just randomly shut off during its normal run time. I started it manually and worked fine.
Then last weekend, it shut off and lost suction. Had to prime. Restarted it. Then it shut off again. There are no signs that it appears to be pulling air in at the skimmers (water level is correct, skimmers empty).

We had similar things happen with our last pump before it died, so I went ahead and had the motor replaced yesterday. I ran the pump overnight and around 10am this morning it shut off again.

Any ideas?

 

[Texas Splash]

Since you actually replaced the motor, it's probably safe to rule that out. So let's back-track some basic things:
1. Power supply breaker not tripping? Serviceable? Confirm good power to pump with meter.
2. Probably GFCI protected. Any signs of moisture nearby? Check for bugs (geckos) in the sub-panel too. Critters can trip breakers once they BBQ.
3. Losing suction for a significant time will overheat any pump, so that's a common denominator between both motors. Loss of prime would most likely be either:
- Partial clog in the water supply line to the pump. If you have both skimmer and main drain, confirm water flow in each.
- Suction side air leak. Typically areas include clear lid and rain plug o-rings silicone? Any valves before the pump operational and not failed internally?
- Weir door/flap not operating properly; getting randomly stuck closed. That'll do it for sure.

Start there and wee if any of those make sense.

 

[Dagobah]

Since you actually replaced the motor, it's probably safe to rule that out. So let's back-track some basic things:
...

That's a great list. I'll work my way through these and let you know.