[Nebster]

There is a little more to the story: I still have not had a chance to replace the scroll fans that exchange the air in the generator compartment, but I HAVE now watched the Powertech ECU shut the generator down with a "high water temp" error when the temp sender was reading 160F.

So, what this surely means is that there is a SECOND temperature sensor, probably on the generator head (or whatever that's called, the thing with the stator and rotor that makes electricity!), that must be in series with the water temp sensor. This second sensor is shutting the genset down when the generator head gets too hot, since the bay can't get fresh air without those fans. But the ECU only has the one "high water temp" error code it can report.

I'm posting this so that the next person who has to diagnose a side-mounted genset with a PT ECU can learn that there may be a different reason, other than coolant vapor lock or radiator fan issues, that a high temp shutdown can occur.

Why Power Tech couldn't be bothered to mention this to me when I spoke with them last week is a mystery.