Back in Mazetlan!
Kievit left Mazatlan on Tuesday morning,4/17, as planned. The wind was light, so we ran the engine at 2000 rpm for two hours. The engine temperature slowly edged up to 185 deg F, then in a manner of minutes shot up to over 200 deg. We shut the engine down and thought, what the hey, we can still run at lower rpm’s and get to where we want to go. Besides, the wind had picked up and we were sailing along nicely throughout the afternoon and much of the night. When the wind died off, we cranked the engine and within minutes the temp shot up to 200 deg. When light came, we were bobbing on a windless sea. Dave drained the coolant from the system and went about checking the cooling system. At one point he found some pieces of black electrical tape blocking one of the lines. Whoever installed the system had added a drain T in the system and had rapped the connections with electrical tape. The ends of the tape had worked lose and were partially blocking the hose line. Seemed that this could have been the problem all along. So, coolant back in and crank the engine. Ten minutes and overheated again! With no other ideas of what to do, we had a decision to make. Sail on to La Paz which was still 160 mi away. The entry and 5 mi channel would be difficult without an engine. Sail on to Los Muertos (about 100mi) where there is a good anchorage but no chance for mechanical help. Sail back to Mazatlan (about 85 mi) where there is fairly good marine services, and the wind almost always favors going southeast at this time of year. So, after 56 hours at sea we are back safely at the dock in Marina Mazatlan. Entry through the breakwater and channel where a bit tricky under sail, but we made it without incident. This morning, Dave went back through the whole cooling system and can only figure out that the coolant isn’t circulating through the engine and heat exchanger. It seems that the mechanical pump on the engine isn’t working, but that is unlikely as there is no unusual noise of leaking at the water pump. Now, we are waiting for a mechanic to come and have a look at the engine.
The mechanic was here and there is a solution. His thought was the same as mine, that is; there must be something wrong with the water pump. He removed it and all looked fine. The other possibility was an airlock in the system. This should be remedied by opening a bleed valve which I had tried many times. It didn’t work for him either. Next, mechanic took the hose lose that feeds the hot engine coolant to the hot water heater and could see no flow in the hose with the engine running. Next, he took free the return hose from the water heater. Then he shook his head. Next, with the engine running, he poured a cupful of water down the connection nipple for the hot water return. This is positioned just over the water pump. In seconds, the engine temp dropped from 220 to 160 deg. Essentially, all he did was prime the pump. It’s another lesson learned for me.
The question is, how did air get into the system in the first place? There is a possibility of a leak at the exhaust manifold. The leak would let coolant out into the exhaust gasses and maybe air in. White smoke in the exhaust stream that I had been noticing recently could result from such a problem. Anyhow, I had been aware of the potential problem for some time and had actually ordered and received (Thanks again Jane.) two new gaskets to fix the problem. I tried to do the job at sea, but it turned out to be more difficult than I thought. The mechanic is coming back Monday to do this job. I hope then that we will be off to sea for our last six weeks in Mexico.

ps from Marj.. Characteristically, Dave did not mention that, uncharacteristically, he felt bad though the night, and became sick as a dog as he was draining coolant from engine - which is a nasty job, even in harbor, much less open sea. He is just now beginning to feel WELL, as opposed to better. We figure it was a virus or such, rather than sea sickness. Much of the time we were out, Dave was sleeping while I was pleasantly sailing along, going nowhere at 2-5 knots. Great there were no emergencies!