… and it happened “out there”, just as Captain Ron always said it would.
Before I go further, I should make it clear that this is not one of those “I was almost run down by a supertanker 30-foot seas while I was bailing furiously to keep my boat from sinking” stories. I read and enjoy those; there’s always something to learn from disaster or virtual disaster stories. This is more of a story about what (mostly) went right. As a result, it’s a bit nerdy at the beginning. The emotional part of the story comes later. Now that you know whether to continue reading, I’ll begin.
Two years ago, our auxiliary engine, a Yanmar 3YM30, reached its 1,000 hour mark. That signals a host of changes and replacements, one of which is replacing the impeller. (For those readers who do not regularly depend upon a marine Diesel engine, the impeller is a rubber wheel with water vanes, much like a water wheel, which pushes seawater into the engine in order to cool it. These vanes go through major flexing and eventually break down with use.) The impeller and the belts that drive the water pump and alternator are the Achilles heels of the marine Diesel engine. Selah carries spares for those items at all times.
Our 2009 Hunter 36 sailboat presents some design challenges to replacing the impeller, which is an interior part of the water pump. While the cover to the impeller is at the front of the engine, direct access is prevented by the last step of the companionway. (Oddly, earlier iterations of this boat design do allow for direct access.) The result is that one is forced to work vertically on something that is designed to work horizontally.
I had regularly checked the impeller visually during the engine’s first 1,000 hours, using a flashlight and an automotive mechanic’s mirror. It’s what the Yanmar manual recommends. A good friend of mine, a boat dealer of some considerable experience, told me that impellers should last about 1,000 hours. My visual inspection at 1,000 hours showed an intact impeller. But I wanted to ensure that it would not break down in a seaway, so I scheduled an impeller change.
My go-to when I am about to do something on the boat that I have never attempted is to enlist someone who has done the task to help me do it on my boat. Two years ago, when I was at the 1,000 hour mark, I asked David Weale, a fellow sailor who is a member of the Hunter Association of Puget Sound, to help me. Dave is an engineer who owns a similar Hunter; he changes his boat’s impeller every year. The first thing he said when he saw what we had to do, was “Well, you’re going to want to get that access re-done, for a start.”
I damaged the old impeller when Dave and I removed it, and just managed to get the new one in there with the four hands we had. Over a year later, after my entire water pump broke down, a diesel mechanic and I took the better part of an hour tearing out the bottom panel on that same bottom step to replace the pump. Afterwards, I called in a ship’s carpenter from Miller & Miller boatyard, and he found a solution, a deceptively simple one, he assured me, which would both keep the integrity and functionality of the step, and enabled it to be removed and replaced via six screws. Done.
Fast forward about six months, to a sunny, warm Saturday afternoon. The engine now has 1400 hours on it. Linda and I are on Selah, heading out of Eagle Harbor on Bainbridge Island, with our granddaughter Edie and our dog Sofia aboard. We are headed back to Elliott Bay Marina in Seattle. Calm conditions, with 2 knots of wind coming from whichever direction it decided to puff. Not enough to sail, so we are motoring. About 30 minutes into the 75-minute trip, Linda notices that our engine exhaust is billowing grey smoke.
Not a good sign. That color usually means that one has a cooling problem, and the engine is about to overheat. I went below to check the engine: plenty of coolant, and the water pump belt was intact. I carry a laser-guided temperature gun aboard, and I took a reading from two places: the engine temperature was about 30 degrees F higher than normal. Not good. Above me, the cockpit overheat alarm went off, a piercing shriek, and Linda should down the engine.
The impeller was the next likely suspect. The first thing I did was ask Linda to obtain our position. The charts showed us in the middle of the Traffic Separation zone, with North- and South-bound commercial traffic lanes behind us and in front of us, and –since we were dead in the water–no way to navigate.
I asked Linda to take over boat communications from the helm while I worked on replacing the impeller. Our first call was NOT to the Coast Guard. The Traffic Separation scheme that stretches from the north of the Georgia Strait to Olympia, WA is overseen by an international set of four offices, each with their own radius frequency. I asked Linda to call Seattle Traffic, to inform them that we were stranded in the middle of their commercial lane system, and report our position in terms of latitude and longitude.
As soon as she did that, Seattle Traffic began looking at the commercial traffic. A Seattle-bound ferry monitoring the channel responded that they had a visual on us and were altering course to avoid us. Seattle station reported no other commercial traffic, and requested that Linda contact the Coast Guard on channel 16.
In the meantime, I have closed the engine raw water through hull valve, and am (gratefully) backing out six screws from the now removable bottom panel. I unscrew the cover, and there is my 400-hour impeller, minus one of its rubber vanes. Even better: once I have pulled it out, I also see the broken vane. This means that the vane is not currently floating through our cooling system, about to cause a blockage that is hard to repair at sea.
I relay both these pieces of information to Linda at the helm, so that she knows what’s going on, and how much time it might take for me to rectify the problem.
Linda’s hours of listening to other distress calls has clearly helped. As I am working below decks, I hear her anticipating the usual questions: three people and a dog on board, all have their life jackets, we are currently without propulsion but actively working on the problem and– yes we have an anchor and 300 feet of chain that we could suspend over the +500ft depths below us, should they deem that necessary/advisable. Mobile phone number? Here’s the skipper’s.
My phone rings almost immediately. Given that my hands are currently occupied, I don’t answer until the third time they try it. My first indication that I am in adrenaline overload is when I finish a response with “Over.” The nice captain chuckles as he reminds me that I’m on a cell phone. Would I please call back once we are underway?
My second indication is my inability to find the cover for the impeller housing. Nothing is repaired if I don’t find it. The six screws I removed from the panel and the knurled knobs that hold on the impeller cover are in the plastic parts bin I use whenever I’m working on board. I revisit that three times to make sure that I have not missed the much larger impeller cover, which turns out to be……. where I left it, next to the storage location for engine replacement parts, and out of my line of sight.
I install the cover, open the through hull, and Linda starts the engine. No alarm, and the temperature reads normal. As instructed, I call the Coast Guard to let them know we are underway.
So here are my takeaways:
What We Did Right
Linda alerted me to the potential problem as soon as she saw it.
As soon as we agreed that it WAS a problem, we began the diagnosis.
We divided up duties quickly and effectively: Linda maintained and communicated our situational awareness, as well as kept an active watch on the boat and crew, while I worked on diagnosis and repair.
Linda was prepared to communicate clearly and efficiently.
We communicated with specific authorities, in order of navigational safety. (If we had not been in a commercial shipping lane, we would have called the Coast Guard first, and let them deal with any necessary announcements to other vessels in the area.)
I kept Linda informed of my progress.
Linda maintained an active watch during my work.
We had the necessary spares on board, and had anticipated having to replace them efficiently.
What We’ll Do Better Next Time:
A better job of agreeing on whether we have a problem to investigate. We probably ran the engine 10 minutes longer than we needed to, while we discussed when the smoke began, and what it might mean. I now know that 30F degrees above normal is too high. On the other other hand, we might also have found ourselves stranded in the southerly traffic lane, as opposed to the (relatively safer) Traffic Separation Zone.
I was rushed in my replacement task, and as a result, failed to lubricate the impeller with glycerine and replace the seal for the cover, both of which are recommended to avoid premature failure of the replacement. I did that after we returned to port. My new protocol is to create replacement KITS, with all of the necessary items in one plastic bag. A checklist in that bag would also be helpful.
Every removed part goes in the same plastic bin, so it can be easily located as needed.