I went out to our boat last week to do some end-of-the-season prep and, as usual, I turned on the breakers for the cabin lights and the water pump. The water pump ran briefly, perhaps two or three seconds, and then shut off. I had noticed this behavior for several months but I didn't think much about it. I figured that one of the faucets had drained off the pressure during our absence.
While I was out on the foredeck, I noticed that the bilge pump was discharging for several seconds, shutting off and then repeating the discharge. I went below to check the bilge and heard the water pump running continuously indicating a plumbing leak rather than a hull leak. I shut the water pump off and started investigating. The first place I looked was the water heater and, sure enough, the pan below the heater had water in it and when I turned the water pump back on I could hear water running inside the heater.
I pulled the water heater out and took it home where I removed the aluminum surround and found a hole in the tank (first photo).
I was able to find the same Kuuma 11841 heater at Defender Marine for a good price including free shipping - it will be arriving later this week. The same model is also available on Amazon at a slightly higher price.
I was interested to know what the internals of the water heater look like so I cut out a panel using an abrasive disc (second photo). The larger diameter tube is the heat exchanger. The total length of that tube is about 68 inches so if the internal diameter is 5/8" that would indicate a capacity of about 12 fluid ounces (about 0.35 liters).
The third photo shows the leak from the inside on the panel I removed.
I am in the process of re-configuring our Webasto diesel heater to that we can switch between having the engine heat the domestic water and having the Webasto heat it. The significance of that is that I was going to have to partially drain the antifreeze out of the water heater and the hoses between it and the engine so the timing of this failure was fortuitous.
While I was out on the foredeck, I noticed that the bilge pump was discharging for several seconds, shutting off and then repeating the discharge. I went below to check the bilge and heard the water pump running continuously indicating a plumbing leak rather than a hull leak. I shut the water pump off and started investigating. The first place I looked was the water heater and, sure enough, the pan below the heater had water in it and when I turned the water pump back on I could hear water running inside the heater.
I pulled the water heater out and took it home where I removed the aluminum surround and found a hole in the tank (first photo).
I was able to find the same Kuuma 11841 heater at Defender Marine for a good price including free shipping - it will be arriving later this week. The same model is also available on Amazon at a slightly higher price.
I was interested to know what the internals of the water heater look like so I cut out a panel using an abrasive disc (second photo). The larger diameter tube is the heat exchanger. The total length of that tube is about 68 inches so if the internal diameter is 5/8" that would indicate a capacity of about 12 fluid ounces (about 0.35 liters).
The third photo shows the leak from the inside on the panel I removed.
I am in the process of re-configuring our Webasto diesel heater to that we can switch between having the engine heat the domestic water and having the Webasto heat it. The significance of that is that I was going to have to partially drain the antifreeze out of the water heater and the hoses between it and the engine so the timing of this failure was fortuitous.
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