horns don't work

[jim rosenthal]

I could have sworn I started a thread about this, but maybe not; I can't find it. In any case, here we go:

Last summer I took the trumpets off my Raritan/Fiamm airhorns to paint the boat. When I put them back on, the horns no longer worked. The compressor worked, blew air and all, no problem with the electric, but the horns made no sound at all.

I fiddled with them a bit, got nowhere, and (being busy) got a good marine services company to look at them. They reported that the horns did work from an air tank, but not from the compressor, and that they had tried a replacement generic horn compressor, and that they did not make any sound from that either, so they felt a larger compressor was needed. I ordered a new Alpex compressor, the 999 model, and hooked it in, and the horns STILL don't work.

It's pretty hot up here in MD, and much of this work requires being pretzeled into the bridge console, not a large space. So at the end of the day today, I took the horns off the boat, removed the compressor that I just put in, and brought everything home and took it apart.

There is some corrosion to one of the copper diaphragms, but no holes in either one. Everything really looks pretty good in there. I am going to clean everything up and reassemble them, and see if they work. These are simple devices- the diaphragm is the only moving part. They don't seem to have been frozen. They are, incidentally, no longer available from Fiamm.

This set of horns worked for 42 years with a small compressor, pretty much identical to the one I just put in. I am not even sure the old one was actually bad, although I don't mind having a new one in there. What I DO mind is that the boat has lost her voice. I liked the original horns, they came on the boat, and I would like them to work as they did. I should also mention that the horns and bells have been off before and this didn't happen.

If anyone has anything to suggest, I appreciate, in advance, any help offered. And if I has this in a prior thread, my apologies; we're all getting old and absent-minded.

 

[SeaEric]

If I recall the thread, the concensus was that the bells were screwed in too far. My original twin horns work about 1/2 ie one blows and the other is silent. I have screwed with them - literally, and still the one is silent. I'm looking forward to your solution.

 

[Canuck Dennis]

Older, real older style car horns used to be adjustable at the diaphragm ?? maybe those are the ones on my 1936 Morris 8 were ..lol...

 

[jim rosenthal]

I've heard it both ways: that the back of the trumpet needs to touch the diaphragm, and that it doesn't. Both diaphragms do show a ring mark where the back of the trumpet was very close, if not touching.

I wish I knew who to call for this. My current plan is to clean everything up (I just got done buffing the brass air conduits clean) and then reassemble everything. I will have to make some new gaskets which is fine. I have a 12v battery here that I can charge up and use to run the compressor. At that point, I can adjust the trumpets in and out and see if I can get them to work.

I only have a small garage. If they can be made to work in there, I will have a perfect excuse for not hearing anyone for a week.

 

[Finalee]

I sprayed wd40 in mine and they started working again.

 

[bobk]

Jim, When the mechanic reported the horns worked off an air tank, was the tank pressure similar to that of the boat compressor? If so, that suggests you need more air volume (vs pressure) to make them work and you might get that by hooking up both compressors to a "T" right in front of the horns. That quick shot of WD-40 might also help.

Bobk

 

[davidwigler]

I have a pair of the Buehl horns connected to an engine-compressor supplied air tank in the port e.r. With the engine off they work well. When the port engine is running, they sound puny if working at all. Strange.

Can they be supplied by a DC compressor with no tank?

 

[Beckytek]

It makes a big difference as to how far the horns are screwed into the rear fixture. Have some body on the horn button as you screw the horns in or out. At one point they will start working. then do the same with the other one.

 

[jim rosenthal]

Exactly. But since I was working alone on this, I just brought everything home, set up a battery and charger in the garage, took them apart and cleaned everything (and verified that there were no holes in the diaphragms) and reassembled everything. It turns out that the way you set the horns is you gently screw them all the way in (not too hard) and then turn the air on and begin unscrewing them a little at a time. When they start blowing, you go a little further; then they stop, and you go back in a bit. It doesn't take too long to find the sweet spot where they are the loudest. Then you tighten the lock nut. You do this with one horn at a time, incidentally, as noted above.

I have to rig a better mounting system for the compressor. And I replaced all the tubing etc and I'm going to clean up the wiring. But I've made some progress and I am grateful I got to hear them today. I don't want my boat to sound different than she used to.

 

[jim rosenthal]

I have a pair of the Buehl horns connected to an engine-compressor supplied air tank in the port e.r. With the engine off they work well. When the port engine is running, they sound puny if working at all. Strange.

Can they be supplied by a DC compressor with no tank?

Yes, they can. You would have to set up a 32v dc compressor, though, which might not be that easy to find. Buell or Kahlenberg make them, I think.

 

[Tim Powell]

I belive that my 52c had a air compressor in the engine room there was evidence of sutch.There was a plastic tube which was cut off and the compressor was gone. I riped out all the old stuff and purchase a new compressor from the local surpluss store it was 24 volt . I lockated it under the brow on the bridge and put the hornes on the hardtop, This helped to keep the sides cleaner looking.
I looked today the compressor has one tank and maintaines 30 pounds. The hornes did not work .I took them apart and cleaned them, I had the hornes rechromed and after putting them back together and adjusted the set screw on the back till they blew. I put air to them and adjusted untill they made noise and a heck of a lot of it. Not sure but i belive the cleaning of the diaphram and the inside where the thing rattles made the diffrence....Also they would not sound good and perky untill the air pressure was at around 25 to 30 psi. As Forest Gump said all i got to say about that. Good luck Tim

 

[rsmith]

Check your solenoid valve for crap. If they blow on the compressor at home but not on the boat it's an air flow problem

 

[Avenger]

The compressors that run when you push the horn button only make a few PSI. More of an air pump than a compressor.

Compressors that fill a tank that feeds a regulator usually run much higher pressures.

Be sure you understand what you're calling a compressor.

 

[jim rosenthal]

Right. It is more like an air pump, I guess- not that it moves all that much air, either. But now it is enough to make the horns blow.

 

[SeaEric]

Thanks to Dr Rosenthal who visited my boat today, my horns now work properly. Thanks Jim!

 

[jim rosenthal]

And they work! If I could post a soundfile, I would, but you all know what they sound like. The most important thing is that they sound like they used to...

While you're in theres: I cleaned up some loose wiring (the 12v bus for the fly bridge was mounted to the cabin roof inside the bridge, on a piece of plywood put in there 42 years ago. The plywood finally fell apart. I used a scrap of Azek I had sitting around to replace it. Also mounted the horn compressor to the deck inside the bridge; there is a piece of wood glued to the inside of the bridge itself, but it looks a little suspect and the weight of the compressor may pull it down.

And, I fitted my new Pompanette helm chair. Had to take the plastic bushing off the column- I guess it's metal on metal, which means I'll take it off and grease it. Looks good. Now I can get the boat detailed....

 

[SeaEric]

As you know, I replaced Pompanette chairs and pedestals with new. They did not come with plastic bushings so it is metal to metal. The chair hardware was installed with a little white grease. That's probably a good choice for the pedestal to spider base contact points as well.

 

[jim rosenthal]

Righto, and I was going to call and ask on that....

 

[dlpurvis]

We have had problems with the horns, Grover Horns, found the spring behind the diaphragm was rusted out on one. Grover will sell you the bell and base for $115. A new horn is $1025 but they tell you to check with their vendors, they can sell them cheaper. Since the base is striped I was going to braze the horn to the base, but the $115 solves the whole problem. Thanks for the other info, did not know about adjusting. Makes sense now that you explained.

 

[jim rosenthal]

Didn't know of them. Are Grover horns the same Fiamm/Raritan ones I have and Eric has? Can you post contact information if you have it?