So here was the plan, Saturday morning I would get up early, and do a few chores around the house. My wife, Barbara was getting her hair done, so that would give me a chance to slip out for a couple hour sail before I needed to be front and center to spend the rest of the day with Barbara doing the things we planned to do. . Perfect!
Saturday morning, chores done and many multiple layers donned, I sauntered down to the dock. As I walked down the stairs to the dock I realized that Friday night's northerlies had lowered the tide sufficiently that the channel out of Mill Creek into Whitehall Bay was probably too shallow for Synergy to pass.
No big deal thought I, as I warmed up the engine, ran the jib sheets, and removed the sail cover. I now formed a new plan. I would simply sail in the Creek. It had been a long time since I had sailed the length of Mill Creek and so I figured that it would be a low-key beat up the creek and a slow broad reach home… That worked for me.
But as those of us with an older diesel might tell you, we tend to watch the color of the exhaust with a the intensity of papal followers staring at the Sistine Chapel smoke stack for even the faintest clues as to the internal deliberations of the College of Cardinals, or as for us old diesel folks, for the internal deliberations of our engines. The general clues are black or gray smoke is unburned fuel (maybe injectors, injector pump setting, bad fuel), Bluish smoke is burning lube oil (perhaps cylinder walls damage, bad rings, valve guides) and white smoke is water vapor (overheating, bad mixing elbow).
In dead of winter, Synergy's exhaust tends to waft as thin white clouds that disburse a foot or two behind the transom. After some testing and checking, years ago I concluded hose thin white emissions are simply the warm moist air from the exhaust hitting the cold air of winter. It is the diesel exhaust equivalent of seeing your breath on a cold winter's day.
But this winter the clouds were thicker and lasted longer than usual. I mentally concluded that it was probably just that the air was cooler or something innocuous like that. But Saturday was warmer, and as I motored out into the creek, I observed that the cloud remained thicker and denser than it should have been for the air temperature. I put the engine in neutral, and let it idle as I watched the exhaust for a few minutes. It seemed like there wasn’t quite as much water coming out of the exhaust as usual and so reluctantly, I turned back around and went back into the slip.
The new plan, if you could call it that, was the “Boats can’t live by going sailing alone plan”. That plan became doing a bit of diagnostics and maintenance. Back at the dock, I checked the intake thru-hull to make sure it was fully open. It was. Even though the maintenance log showed that the impeller had been replaced roughly a year and a half prior, and been replaced less than 30 engine hours earlier, I opened the raw water pump to check the impeller. It looked good, but since the pump was open, I replaced the otherwise perfect looking impeller.
Then I did a bucket test with the engine pumping water from a bucket of seawater rather than through the thru-hull. The flow was definitely much better from the bucket test, so the problem wasn’t with the engine. The problem lie somewhere between the water pump and intake thruhull. I turned on the water to the dock, back flushed the system, hooked everything back up again, and started the engine and let it run in gear in the slip. Voila, the water flow was normal, the white cloud was gone, but, alas, so was my alloted time to go sailing.