Chasing a leak

Ms. Betttencourt's hull is desert dry. There are no water leaks. But the engine presented a different situation recently. There was an air leak somewhere in the fuel system. Diesel engines won't start with air in the fuel system.

According to the log book, I had "cured" this problem five times since I changed the primary and secondary fuel filters on November 22. The work involved checking for leaks in every possible location, tightening stuff and bleeding air from various engine orifices. Each of these fixes resulted in easy starts upon completion, followed by failures to start a few hours later.

Of course, after each "cure" I confidently put the middle cabin back together. This is the point where fruitless fixes get to be really tedious. It is not easy to get to the engine on this boat.

Three cabin deck panels have to come up. The seat must be disconnected and folded back. The forward cabin bulkhead must be hinged forward. Only then may the engine box cover be lifted up and aft to expose the power plant.

Anyway, after lunch yesterday, I started on fix number six -- by opening everything up -- again.

I began at the fuel tank and re-checked every connection. Fuel pickup.  Lift pump. Primary filter. Secondary filter. Injection pump. The air was heavy with the smell of diesel fuel. Why is that?

This clue led me to a location outside the engine box where the 10-micron Racor primary fuel filter is mounted. There should not have been diesel fuel in the bilge under that filter. But there was.

While I had checked the fuel line connections to the filter head fitting multiple times, it had never occurred to me that the filter cartridge itself might be leaking. I had apparently failed to fully tighten the cartridge when I installed it in November. It would leak fuel with the engine running, then suck air as the engine cooled after shutdown. Not a lot of air, but enough to make starting problematic.

I hand-tightened the filter cartridge another half turn, bled air from that point through the injector pump and at each of the three injectors. The engine started easily. That was yesterday. It also started easily at 0800 and 1400 today. Maybe fix number 6 is a success.

I will wait until tomorrow and start it at least a couple of more times before I declare victory and reassemble the middle cabin -- yet again.

Meanwhile, cruise plans have become uncertain. My friend Major can't get away in January and other cruising buddies are previously committed.

Maybe I'll just stay home and repaint the dashboard and the middle cabin.