We have power

The Cummins 6B5.9M engine has a plaque showing 1991 as the year of manufacture. The instrument/control panel has a date of manufacture of in 1994. We have a sales receipt showing the previous owner purchased the engine new in 1996. It’s never been used so it seemed reasonable to bench test the engine before putting the motor into Mahdee. We plugged the panel into the engine and … nothing happened. It turns out that the engine harness wasn’t quite complete. There were a number of “extra” wires on the engine harness. One of the extras was the control panel ground; it had no place to connect to. After making the missing piece and connecting the ground, the starter engaged … and to my great surprise, the motor instantly started right up as if it were warmed up and ready to go rather than having just come out of the crate where it has been for 12 years. John was surprised to hear it start and even more surprised that the exhaust was clear and smoke free–we were expecting clouds of black smoke on the initial startup. I shut it off and called for Brenda to assist because it was almost a full time job just keeping the raw water container full using a garden hose. On the next test, it again started right up. There is some corrosion in the cooling system which we will need to take care of before installing the motor.

The Onan 8kw genset was not as simple. The previous owner of Mahdee had been routinely rotating the Cummins engine to move all the parts and keep it limber. That didn’t happen with the Onan and it wouldn’t start. I couldn’t get fuel to the high pressure system. I thought the problem was air in the fuel lines. But, no amount of bleeding helped. I finally asked another boat owner, Tom, who is more familiar with diesel engines, to make sure I wasn’t missing something. The engine ran fine on WD40 sprayed in the intake and Tom immediately zeroed in on the fuel shutoff lever. Inside, the fuel control rack was frozen. We now own a manual for this no-longer-manufactured generator. Today, after obtaining the manual for the Onan and expecting to rebuild the fuel control, I got the rack freed and the genset finally ran on its own.

These motors are almost ready to install. The stringers are done for the Onan, and as soon as the parts for the shaftlog, stern bearing and packing assembly are all here and installed, I will put in the bed for the Cummins.

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