Try installing another washer in between the mounting bracket and the new airwing cover .... this will give the horn more room to vibrate. Just my .02

 

Yeah, it definitely sounds like you need to find a way to create some additional clearance between the new cover and the horn itself. As I said above, if it can't vibrate, it won't make sound. I'm going out of town in the morning but if you haven't resolved this by the weekend I'll take my horn apart when I get back and see what I can see... Good luck in the meantime.

 

thanks for the help, I'll be working on it.

 

My take on it from the keyboard....


The horn has a ground wire already, it is not an electrical problem unless the ground wire is not making solid ground.
The horn is acoustically isolated from ground to resonate more freely.
If a lug was shorting to metal, you would be blowing fuses.

I think by tightening the last nut, you are distorting the horn itself. The horn has to resonate freely (there is an electromagnet inside that has a vibrating reed to create the sound) If you distort (bind, twist, contort) the actual horn itself, it possibly could not resonate properly. The electromagnet has to have free space, like a speaker.

And I may be totally way off base but that is my best diagnosis from reading the thread.

 

I agree with you chops, I don't think it is a ground issue. However, why does it work if I tighten it down on the OEM cover, and not when I tighten it down on the new cover?

That is what is puzzling me. The horn works fine when it is not in any cover at all, so that tells me it is grounding fine.

 

Well, based on everything you have tried, and the fact the service manual explicitly says to not let the horn touch the cover, I would focus on insulating any part of the cover that could possibly make contact with the horn.

 

My bet is that it isn't an electrical problem and it is a space problem. Can you install a small thin nut on the stud under the cover to act as a stop when you tighten the cover down?

 

I will try both of those ideas.

 

Please post the results.
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