Westerbeke Generator Impellor Replacement?

The electric pump is an interesting option. Thanks for the link.

I was just at the boat and had a good look. There is no way the sea water pump can be serviced from underneath. The only option now is to move the unit. After some head scratching, Sea Ray technicians in FL have also suggested that moving the unit may be the only option. I have decided that a temporary support bar across the stringers would be needed, then it appears that the following needs to be done:
Disconnect oil drain hose at 90 degree union and cap the fitting temporarily;
Disconnect main ground cable;
Disconnect 12VDC ground cable;
Disconnect seawater hose;
Disconnect exhaust cooling hose at siphon break;
Disconnect starter positive lead;
Loosen stbd fwd mounting bolt;
Remove 3 remaining mounting boots;
Swing genset forward onto support bar.

Hopefully, this helps others with the same model or similar setup. If the procedure becomes too labour intensive, I will hard wire an electric pump as mhwhit1 did. I will know the answer in the spring. Thanks for everyone’s input.

I need to move it a bit more than 4 ". I would say 30 degrees or a little more. The engine end is to port. The fuel lines come in on the generator end. They can stay put as they are at the pivot. All of the lines, wires and hoses I mentionned need to be disconnected in order to move it even a little. It seems like a lot but really it's just twisting a wrench or two. The only messy part would be the oil drain hose. That needs to be capped after undoing the union. Above is the underside of the cockpit and only a few inches of space. Tricky still, will be having enough leverage to lift slightly as I pull forward without putting my back out. Its about 425 lbs or so. Still like to hear what the mechanic has to say though.

And that valve would be more secure than say the hose running from the pan to the valve manifold at the exchanger pump. It is tight at the pan drain but perhaps a small LP valve would fit. Thanks for the idea.

Update. I removed the output electrical cables, ground wire, the exhaust hose, two raw water hoses, three mounting bolts, loosened the fourth and swung the unit about 45 degrees until the fuel line slack was taken up. I had to place a 3/4 inch board across the stringers for support. I was able to switch out the impeller and tighten a couple of seemingly loose hose clamps all left handed. The impeller, by the way, looked and felt really good, so into the emergency parts box it went. All in all 2 hours in a cool engine room. I can live with that.