Pilothouse Roof Mounted Trumpet Horn Vibrates at Low RPM(39)s-gctid367059

[Guest]

Hello Fellow Boaters:

I have a trumpet horn mounted on my 1992 4588 Motoryacht pilothouse roof. At low RPM's it will sometimes vibrate. I cannot locate any way to tighten the horn down to the firberglass rooftop. The horn does not appear to have any screws to tighten. The inside of the pilothouse has a beautiful headliner which I obviously do not want to take apart. Has anyone had this situation before? I am certain that someone knows how to tighten these original air horns down. Please let know. Thanks

Captain Paul

[Guest]

Our 38 MY dual SS trumpet horns were mounted to the FB cowling with SS bolts on the outside secured by washers & nylock nuts on the inside, so only way to tighten is with wrench inside and screw driver outside. Good luck, Doug S.

[Papa_Charlie]

Pictures would be very helpful for this. But if you cannot see any type of fasteners, I would have to wonder if the trumpets themselves are held in position by a two piece bracket. If so then if you remove the upper piece and the horn, then you may find the fastener under there. If you horn is vibrating, then it is loose, if it is loose then it was not properly bedded, if not properly bedded then it is a leak point and should be corrected.

Sorry cannot be more help without more info.

[smitty477]

"I cannot locate any way to tighten the horn down to the firberglass rooftop."

On most of these installs the horns are on the stb side just above the pilotohuse door. If you stand at the door and look inside where the horn is located you may see that there is a ridged covered side panel mounted high above the electrical switching board. That panel should have a few covered and hidded screws which when removed will give you access to the under side of that mount.

Hope this helps

[Destiny_4588]

You can access the bolts/nuts from the pilothouse, you remove the teak trim and the reach the nuts with an open end wrench.

[capnken]

ditto on the last post....

I took mine off, cleaned them up (not working), removed trumpet ends, diaphram held to light had holes... measured thickness and bought same shim stock (brass) and used old as template and made new. to 'tune' it, I used a rubber mallet on the end, 1st whack, got a tone, second wack got a real good honk! Works great now. Ken

[iceclimber]

I think the solution is to never be at low RPM's. I mean, it might cost you a little more in fuel - but you will get everywhere faster. Another suggestion is to trade boats with me. My horn doesn't do that at any RPM's. I stand ready to assist you Captain.

[mmichellich]

iceclimber wrote:
I think the solution is to never be at low RPM's. I mean, it might cost you a little more in fuel - but you will get everywhere faster. Another suggestion is to trade boats with me. My horn doesn't do that at any RPM's. I stand ready to assist you Captain.

Most us us have a hard time exiting and entering our slip on a plane, but someone might know how to do it. Please enlighten us.

[iceclimber]

mmichellich wrote:
Most us us have a hard time exiting and entering our slip on a plane, but someone might know how to do it. Please enlighten us.

I thought we were talking about boats and not planes. Everyone knows planes go in a hanger.

[Guest]

Make a rubber gasket too to install under the base and insulate your issue.