Water heater plumbing

[GordMay]

LPG gas hose should be marked: UL21; CAN/CGA–8.1–M86 Type I
Other specifications, that the hose may be marked with:
Hoses and Fittings shall have no less than 2400 kPa (2.4 Mpa, or 350 psig) rated working pressure, in liquefied petroleum gas service.
The standard supply pressure, for Propane appliances, is 37 mbar (14" water gauge),

[JetPowers]

Status update, white pump. I hooked up a 12V 10Amp regulated PS at the junction of the red/black wire nuts that leave the motor then fork both to somewhere I can't locate (probably the battery bank) and down deep into the bilge (a netherland I can't even dream of following).
Thankfully it powered up and provided very strong suction. I allowed some PG antifreeze to be sucked in.

So my best guess is that it is indeed a grey water (shower as suggested?) pump on a float. I might install a manual/auto switch.
I am disappointed it's not a black water discharge. I'd like to pump out offshore.
Thank you all for providing so much insight.

[JetPowers]

Originally Posted by GordMay

LPG gas hose should be marked: UL21; CAN/CGA–8.1–M86 Type I
Other specifications, that the hose may be marked with:
Hoses and Fittings shall have no less than 2400 kPa (2.4 Mpa, or 350 psig) rated working pressure, in liquefied petroleum gas service.
The standard supply pressure, for Propane appliances, is 37 mbar (14" water gauge),

Just saw this after the fact. Thank you I will look next time I'm there.