Mystical Water Heater and Engine Hoses

Yes, that is correct, I did say a mystical, some might say magical hot water heater. It all started several years ago onboard our Mariner 40 sailboat Sea Trek. Our 6 or 7 year old hot water heater had developed a leak which we could not stop so we ordered a replacement of the exact same model and configuration, not wanting to re-plumb and rewire everything. On the day the replacement arrived, the existing hot water heater stopped leaking and is still in the boat, working fine several years later after we sold her last year. Just a few months ago on our trip up the ICW from Beaufort, South Carolina to the Chesapeake, we stopped in Southport so Susan could rent a car and drive to Maryland for a job interview. While at the marina in Southport, I discovered the existing hot water heater in Beach House was leaking and the tank was pretty rusted on the outside. The magical hot water heater that we have been carrying around for several years was in the back of our van, at a friend's house in Maryland, waiting for us to arrive. I called Susan and asked her to stop by the van and pick up the water heater since I feared the one on Beach House might fail on us along the way. Since we had this as a spare, it should be with us on the boat. Well sure enough, as soon as she returned to the boat with this water heater, the old unit immediately stopped leaking without us even touching it. We finished the trip to the Chesapeake and after a month or more the water heater still showed no signs of leaking.


But I knew that at some point the magic would wear off and the old heater would eventually rust through the bottom. I have seen many of these do exactly that in the past so we decided to install the spare water heater and not take any chances. We were also getting tired of hauling this thing around and having it take up storage space. It needed to be planned out so the swap could happen quickly and we would not be without hot water or even water at all. As a last resort I could connect it up to bypass the heater for a while but we preferred to just get it done. Over the next week I planned out the replacement and ordered all of the various parts I needed. The fittings on the old tank were not ideal and in bad shape so they were all replaced. The water lines were connected as a combination of copper tubing and short hose pieces clamped to the copper tubing. We have had these come apart on us in the past and dump the entire contents of our fresh water tank since the hose eventually slides off the tubing from the water pressure, so that had to go. That meant we needed fittings that would attach to the compression fittings on the existing copper lines and then allow a hose barb attachment. Not as easy as we thought but we did eventually find an ACE Hardware with all of the parts we needed to make them up.


Another part of this project involved the engine heater hoses that heat the water in the tank when the engine is running. These were also a hodge podge of hose and copper tubing that I had on my list to replace since we first bought the boat. Now was a good time to do that since they would have to be disconnected and the fresh water coolant drained anyway. As it was, the engine heater hoses were connected via a T fitting on the hose that leaves the fresh water pump and connects to the engine exhaust manifold. A hose to hose connection, although working and came from the factory that way, was not the way we would like to see it done. We contacted our experts at American Diesel and of course they had the solution and the correct way to make the hose connection. There is a kit sold to connect the hose on the side of the engine block and another attachment from the faceplate for the fresh water coolant hose coming from the pump to the front end of the exhaust manifold. Once we had the kit it requires that you remove the faceplate and drill and tap a hole for the hose barb to connect. Care must be taken in this process so that the hole is in the proper place and the faceplate is not damaged. We also ordered the replacement gasket for the faceplate at the same time.

This is a boat project so it is a given that something will most certainly go wrong. In the process of removing the faceplate, three of the four bolts came out with a little coaxing but the forth lost its head during the coaxing process. (And I almost did too!) This left about a 1/2 to 3/4 inch piece of the bolt sticking out of the manifold once the faceplate was removed. I really wanted to be careful and not damage the manifold itself or break the stud off flush or below the surface in the manifold. In the past I have had great success by spraying with liberal amounts of PB Blaster and following up with liberal amounts of Corrosion Block. I wrap a piece of cloth over it to keep it wet and saturated. But after more than a week of spraying and wrapping, it was apparent it was not going to come out no matter what kind of easy-out, vice grips or anything else I might use. So it was time to call in the experts. A phone call to Jim Stitz from White Marsh Diesel, Inc. at 443-791-9399, brought him down to the boat immediately. In short order, he had the stud removed, the hole cleaned and re-tapped, and ready for the faceplate to be reinstalled. We can't say enough about the prompt, efficient service he provided and would highly recommend him to anyone needing service in the Baltimore area. He took a break in the middle of another job he was working on and came over to help us out. We had heard good things about the work he does.


During all of this time the old hot water heater had been removed as well as all of the fresh water lines from the water system and the old engine coolant lines. Since the area around the hot water heater was in serious need of attention, we cleaned, sanded and painted the entire area and even treated a few rust spots on the side of the fuel tank which is right next to the water heater. We like to use Zinsser Bulls Eye 1-2-3 Primer to paint the bilges and inside lockers, etc. This really needs no sanding, just a clean surface, covers well, dries in about an hour, and has built in mildew and mold resistance. And it is a whole lot cheaper than paints in a marine supply store.


Once the paint was dry the water heater was mounted and secured to the platform. Next the fittings to connect the fresh water hose to the existing copper pipes was attached and the hoses connected to the heater with new hose barbs. At this point the heater could be filled with fresh water and the water system was again functional. To get the tank to fill, a hot water line at a sink needs to be left open until all of the air is purged. The next step was to connect the 110 volt wiring and since it has been our practice to replace the old wiring as we go along, this was no exception. This wiring, probably more so than others, needed replacement since it carries a fair bit of current and did not make a direct run to the circuit breaker on the panel. Once the tank was full, very important prior to applying power, and the wiring connections were made and checked, the unit was turned on and checked for leaks. All was well and we now had a functioning fresh water system with plenty of hot water.


Next the engine hoses needed to be tackled. For the hose we used a 5/8 engine wet exhaust hose. These are probably overkill but they are tough, wire reinforced so they won't collapse on bends, and will probably outlast the engine so won't need to be replaced again. The hoses attach to the hot water heater, then run one to the new fitting we tapped into the face plate, and the other to the new fitting on the side of the engine block. Once they were attached with new hose clamps, and we were sure the clamps were tight enough not to leak, the fresh water cooling system was refilled with a 50/50 mix of
long life anti-freeze. Next the engine was started and allowed to come up to temperature so that the thermostat would open. Once the thermostat opens, additional coolant needs to be added. The engine is shut down, the coolant carefully added, then the engine restarted. We checked the engine hoses at the engine and at the heater as well as the fresh water lines on the system for leaks. The engine was run for a while to let the cooling system pressurize to be sure it would not leak. All went well and the project was completed with success. We just love it when a plan comes together. The big question yet to be answered is how the mystical hot water heater will work now that it is actually installed.