Making the New Water Heater Last

On a boat, particularly in a salt water environment, a lot of corrosion occurs. We usually do what we can on a boat to prevent, or at least delay, the corrosion.  We use materials that are resistant to corrosion, we paint things, and we even use replaceable sacrificial metals to protect other metals.  Well...most of the time anyway...

If you recall in January when I returned to the boat, one of the items I had to replace was the water heater as it had developed a leak.  Well, I ordered one and did the replacement and have to say I've been happy with the results.  Hot running water is a nice thing to have...particularly for washing dishes and taking showers.  And I hadn't really thought of it much until a discussion on the longevity, or lack thereof, of boat water heaters occurred on the Leopard owners Facebook group.  The original poster was wondering...or complaining...about how he was only getting a couple years out of replacement water heaters.  And, of course, the heater he mentioned was the same one that I had just installed.  The usual types of replies about favorite brands and/or how nothing was made well anymore occurred, and then there was one reply that made me think...well duh, why hadn't I thought of that.

A sacrificial anode for the water heater. that
is made by the same company

Even cheap residential water heaters at the local big-box hardware stores come with sacrificial anodes installed.  Why on earth doesn't the boat water heater have one.  We have sacrificial zincs on propellers and propeller shafts, in engine cooling systems, on outboard motors, and just about any other piece of metal that touches the water.  But unlike every house on land, these water heaters don't seem to come with a sacrificial anode.  I guess that is why the boat water heater has a one year warranty when, for about the same price, a residential water heater comes with a 6 year warranty.  Well, as it turns out, you can actually buy a sacrificial anode rod for a boat water heater.  So, not wanting to go through replacing the water heater again in a couple years, I did.

Out with the old...

Since the boat water heater doesn't have a dedicated mounting location for the anode, they are designed to replace the existing drain valve on the water heater.  It was a bit of a pain to remove the plastic drain valve (it would have been much easier if I had known to do this before I installed the water heater...which is why I'm telling you about it now) as there is limited clearance with all the connections on the front.  Installing the anode with the integrated drain valve is easier.

...in with the new.

While it may look like the drain valve is much smaller now, the actual opening inside that plastic valve is not much, if any, larger than on the replacement petcock. So I'm sure it will drain equally as slow either way.  Hopefully this $16 addition will extend the life of my new water heater by a few years.

Shiny Props or Battleship Gray

Another task that is easier (no I didn't say easy) to do out of the water than it is in the water is cleaning the props.  But I'm waiting on parts and can't find an excuse to procrastinate any longer, so it is time to tackle that task.  The propellers didn't look as bad as the one on the other leopard I surveyed, but they could still stand a cleaning.

I figured I needed a flexible scraper, a wire brush, some sandpaper, and maybe a Scotch-brite pad or two.  I started with the scraper.  I chipped the remnants of the barnacles and other stuff off...slowly.  This stuff is like cement.  It took quite a while with the scraper before I got down to the bronze.  For the tight spots where I just couldn't work the scraper, I ended up using the wire brush and sandpaper.  After I got the prop clean, I went over it with the sandpaper to get the last bits off the prop.  I think it took about 3 hours per prop to get them reasonably shiny and clean. The truth is, I never used the Scotch-brite, I quickly realized that a Scotch-brite didn't have a chance.

1/3 of a clean prop

Originally, I wasn't intending to coat the propellers with anything, but after all the work, I was re-evaluating that decision.  I couldn't use bottom paint since the ablative paint wouldn't stay on the props for long.  Fortunately, there are a few prop coatings available. In doing my research on propeller coatings, I found out that Rust-oleum Cold Galvanizing Compound is virtually the same stuff as one of the propeller coating products...and at $7, it was an economical alternative to the $22 can of official propeller coating.  So, I got a can of it to give a try.

Shiny prop with sad looking zinc

Painting the propeller was pretty easy.  Simply mask off the area from overspray and apply a couple light coats of paint and let it dry.  The props aren't shiny anymore, but hopefully they'll resist some growth or, at least, may be a bit easier to clean.  Guess I'll know next time we haul the boat how effective it is.

One last task and the props will be ready to go.  That broken piece of metal at the end of the props in the above pictures were the remains of the sacrificial zincs and they obviously needed to be replaced.  Simply remove the alan head bolt holding it on and replace with a new zinc.  Yeah, right.  One zinc came off just fine, the other bolt would not budge.  I broke a hex wrench trying to get it off.  Fortunately, the prior owner had a supply of zincs AND prop nuts, so I ended up having to remove and replace the prop nut as well as the zinc.  I replaced the prop nut, bent up the tab on the keyed washer to lock the nut in place, then installed the zinc with a little Lock-tite on the hex bolt.

Painted prop with unpainted nut and new zinc

So, other than the touch up bottom paint where the stands are covering the bottom, the underwater surfaces should now be ready to go back in the water.