Tony Brooks

Ian, is the maximum torque at zero revs true of the modern style brushless motors that seem preferred for electric boat propulsion.

If you have an isolation valve on the calorifier output it might take a while for the pump to shut off, which might worry you. This is because the air filled calorifier will act as a giant accumulator, so use the PV to vent the air, as Jen said.

Yes, they would be easy as long as the hole in the bulkhead was a compatible size and the cable insulation had not hardened so they could squash down a little if needed.

This ^^^^^^^ Our cruiser stern with appalling self draining channels went about six weeks between visits with a month of very rainy weather and the water in the bilge was till an inch or so below the top of the engine beds. Even when one of the drain tubes rusted through where it met the uxter plate the bilge level only got halfway up the engine beds. If people don't visit to check their boat often enough, that is their problem. In many cases it is the second most expensive purchase after a house. And, no, I would never have a bilge pump set to auto because that will hide developing leaks (like my drain tube) from me, so I don't investigate and rectify.

I doubt it would be easier, one end of each cable would have to be disconnected to get the gland onto the cable and that may even involve the removal of the terminal and the reinstating them.

For completeness, they would/should fail the plastic drain screws that are usually supplied in the base of hose filters. As far as I know the metal one is an additional purchase unless you use (for a new bowl, but possibly not a very old one) a cut down M8 (I think) set screw.

That is all perfectly normal, and it is to prevent the cold water in the calorifier expanding as it heats and eventually splitting the calorifier. If you also have an expansion vessel it would be, as you say, only operate in an emergency, like if the domestic water pump pressure switch stuck closed. Sorry about the Montego bloomer, despite you making it clear it is a Volvo, I got it into my head that is was Perkins MC42. No idea why. I can't see any hoses connected to the supposed lower section where the hoses connect or how/where it connects to the engine. I am not sure that external web is not just strengthening. I think that I would take one of the fittings off and probe to see if that chamber is split or not.