From below it looked like both horns were leaking. I dried it out good and wrapped the air elbow with a paper towel. This morning,with a little overnight rain, they were both wet.
From the top side I could see the roadside horn was visibly compromised and loose but the curb side looked good visually from the roof.
Turned out they were both leaking.
This kinda concerns me because I couldn't see the leak from the top on the curbside horn.
So I took took the rear mounts of both airhorns off by using a stiff thin putty knife and going around the rectangular rear horn mounts.
Then cleaned them down to shiney chrome and clean fiberglass with denatured alcohol.
To install I had some butyl 3/4" wide tape for a Kool o Matic replacement that I changed my mind on.
I glued the old holes with dowels and toothpicks put down the butyl (that stuff seems nice) new screws and followed up with Dicor
Turns out Monaco just screwed this mount to the roof with no gasket of any type. Then Dicored it. It appears the Hadley guide shows a gasket #3
http://www.hadleyadvantage.com/wp-co...structions.pdf that they failed to use. It was just the chrome edge of the mounting foot and then dicored. There aren't even screw holes on the front of the foot (just two on the rear side) so it wasn't a good install as a result of Monaco not using the supplied gaskets. In addition one of the two screws was next to the air line hole (which was way too big) and wasn't holding anything