After replacing the engine and tank as well as a few other bits and pieces, I am almost ready to launch but just realized my horns were not working. In reading the posts, it appears that after all these years, even the replacement horns are still crap. I noted people saying they are on a 3-4 year replacement cycle, with some giving up on electrical horns completely in lieu of air horns. I had to find out why since car horns are not nearly that prone to failure. Granted the salt air is harsh but still there has to be a reason... or three.
Generally these horns are made with a Stainless Steel (SS) cover, a non-SS metal body under the SS cover, then within the body there are few parts that hold a coil, contact and vibrating plate that make the noise as well as a spiral that looks like a shell where the noise exits - BEEP.
So why are they failing if the bracket and cover are SS, giving the appearance of being marine grade, I wondered???
3 reasons as near as I can tell.
1) The SS cover has a gaping slot where the wires exit, which lets water in that settles inside the SS cover against the painted steel body. While the water does seep back out over time, the rust in mine indicates this is still one notable weak point causing structual deterioration that eventually breaks the seal between the parts letting moisture into the body. The only logic in this design is to have a nice shiny SS cover hiding the rust beneath.
2) The rust issue aside, the horn body consists of 3 pieces that are sandwiched together in layers, with a seal between each piece and screws to hold them together. In mine, these seals were badly deteriorated and certainly not doing their job. Also inside the horn body and within the area that is supposed to be sealed are the more sensitive components; the coil, a set of contacts and the plate that is supposed to vibrate and make the noise when voltage/current is applied. There was much too much corrosion of these more sensitive parts as a result of the failed gaskets and resulting moisture for that to happen.
3) The rust, moisture and seal issues aside, the spiral "horn" part that allows the noise to be directed out apparently is a perfect place for bugs to nest. Both of mine were completely full of bug nests, that were layered in such a way that it was clearly several seasons of blissful mating, bringing a whole new meaning to horny ( :doh )
But back to serious business - I have ordered a replacement dual horn. I plan to modify one of the two to a) seal the wire exit (aka water entrance), b) improve the gaskets between the layers in the body and c) add a screen at the mouth of the horn to keep starry eyed critters from getting in.
Please check back in 5 years to see if the unmodified horn failed and the modified horn still works - I'll bet it does.