Update on my westerbeke w-21 progress and more questions of course. I haven't gotten it running yet, but I think I'm pretty close.
I ended up doing the following:
*pumped all the fuel from the tank, rinsed it with fresh diesel and pumped it again before adding new, fresh fuel.
*replaced every hose in the cooling system, raw water impeller, zincs, and thermostat and gaskets. Several of the hoses were pretty soft and looked 'cracky', so I ordered $200 worth of hoses, thermostat for the motor and spent a good 6 hours getting everything installed. I can't imagine what that would have cost if I let a marina loose on that job.
*replaced both fuel filters
*changed engine oil twice
I finally finished putting everything back together yesterday afternoon and was excited to see what would happen. I hooked up the new battery in, turned the main power switch, and turned the key. It turned over readily and willingly so that is good, but I wasn't able to get it to catch and fire up.
I tried with and without glow plugs to no avail. I think I'm close but I have the following concerns that make me hesitant about continuing to crank on the thing:
1. Positive battery cable got HOT. Not warm, but if I had kept my finger on it, I would have been burned. This was after about 20-25 seconds of cranking. The last time I cranked it I saw a little wisp of smoke come from the positive side. I don't know what to make of it. Nothing has changed electrically on the boat, so maybe it always got hot before and I never noticed. Of course the engine rarely needed cranking more than a few seconds.
2. Raw water side not priming. I rerouted the raw water to a bucket just before the raw water strainer, and I'm not seeing it pull. I'm guessing that the impeller just needs to be re-primed, but I don't ever remember having to do that before.
Any thoughts would be greatly appreciated.