The previous evening I'd fired up the generator and it sounded a bit different and soon cut out with a blinking "overheated" error message which tells me that the impeller has once again disintegrated and needed to be replaced. This job is no fun and always takes a long time to complete and I wasn't going to start it at night so I postponed it until I'd finished my morning coffee. I got the generator sound shield removed and soon had the remains of the impeller removed. The tines were gone and I knew that they would clog up the heat exchanger intake and cause the new impeller to fail sooner rather than later so I needed to get those bits out.
Some bright spark at Cummins Onan had chosen to put the cover of the heat exchanger behind the oil filter. Not good, since the engine oil needed to be completely drained in order to remove the oil filter! So the next task was to drain the (almost fresh) oil and remove the oil filter without making too much of a mess. This turned out to be the simplest, easiest and quickest of all generator related tasks for the next two days! I opened up the heat exchanger cap and saw that it was cracked and the rubber seal deformed, so I knew that I wouldn't be replacing it but would need a new part from Electec, the local store that stocks Cummins Onan parts. I used my dentist's tools to get the little pieces out of the heat exchanger and was ready to continue when I saw that my raw water system had had a slow drip leak that had caused the fuel pump (why would any engineer put an electric pump directly beneath a saltwater impeller?) to rust very badly, with big chunks of metal peeling off the pump. I wasn't sure about replacing the pump until I checked the prices at Electec, but saw that it was time to replace the fuel filter which is located under the impeller pump as well and was showing signs of rust as well. That was the beginning of the end...
The fuel filter has a nut welded to the bottom to allow one to use a wrench to remove the filter. I did so, but the filter was very securely stuck and resisted my attempts. After an hour of trying to find purchase and turn the filter I managed to get it turning... but it turned out that the nut broke out and now fuel was dripping/pouring through the opening into the pan beneath the generator despite my having shut off the main fuel line. Now I was getting worried (and a bit dizzy from hanging head below the floorboards in a compartment reeking of diesel fumes. In the end I used two washers around a section of hose pushed together with a clamp vise to stop my bilges filling with diesel and then spent almost 2 hours trying to get the filter off, including puncturing it and trying to lever it. I gave up on that approach and thought I could get better leverage if I removed the whole assembly but the bolts were very hard to reach and once removed I realized that there was no way I could get them back on myself. I used my huge plumber's wrench and crushed the filter and the extra leverage finally got it moving and I replaced the filter, removed my temporary clamp and turned on the main fuel system. I wanted to be able to run the engine in case I dragged anchor or had another problem, since the winds were howling outside and I couldn't let out more scope because of the boat behind me. By now it was late and I was tired, frustrated and worried about getting the generator back up and running. I'd tried to contact Andy at Five Star Yachting with no luck but knew that I couldn't finish the work alone and needed assistance (as well as advice on how to get rid of the diesel spill).


Patriach hard aground The skipper of this big heavy boat ran aground hard (evidently she hadn't looked at the chart or depth sound) and it took 3 tenders an hour to pull her off. Then they had various attempts at anchoring, including one next to me, which weren't working as the boat was in the middle of the channel. I saw them put out fenders so perhaps they opted to go to a dock
(2017-03-07 09:50:07 NIKON D7100 with a "18.0-250.0 mm f/3.5-6.3" lens. [f/5.0, 1/4000s] ISO 640)
Patriach hard aground
Generator prior to major surgery The impeller needed replacing, but this turned out to be only the tip of the iceberg.
(2017-03-07 09:49:39 NIKON D7100 with a "18.0-250.0 mm f/3.5-6.3" lens. [f/3.5, 1/250s] ISO 640)
Generator prior to major surgery
Old and new heat exchanger caps The old (top) cap and gasket were pretty well worn out and certainly wouldn't have been watertight upon reassembly.
(2017-03-07 13:48:22 NIKON D7100 with a "18.0-250.0 mm f/3.5-6.3" lens. [f/3.5, 1/1600s] ISO 640)
Old and new heat exchanger caps
Old fuel filter The hole in the bottom is where a bolt was welded on that is supposed to make tightening and removing the filter easier; but it snapped off rather than get the filter off; making a pretty big hole for fuel to leak
(2017-03-07 16:44:09 NIKON D7100 with a "18.0-250.0 mm f/3.5-6.3" lens. [f/4.5, 1/60s] ISO 640)
Old fuel filter
Deformed and stuck fuel filter There isn't much room for leverage to get to the fuel filter, so I had to remove the assembly holding it to the engine while it continued dripping diesel into the pan under the generator
(2017-03-07 16:34:21 NIKON D7100 with a "18.0-250.0 mm f/3.5-6.3" lens. [f/5.0, 1/60s] ISO 640)
Deformed and stuck fuel filter
Generator leaks and repair The rusty fuel pump at the top, the broken fuel filter underneath the assembly with the 3 fuel lines and the plastic bag full of fuel-absorbing mats which had done their duty. What a mess, with no solution in sight
(2017-03-07 16:34:08 NIKON D7100 with a "18.0-250.0 mm f/3.5-6.3" lens. [f/3.5, 1/60s] ISO 640)
Generator leaks and repair
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