[axaviere]

heres the deal. theres a threaded hole in the bottom where something screws in and is the input for air as well. i can only guess its a threaded hollow tube that screws into the horn mounts thru the roof (semi) or deck (boat) and then gets bloted tight & the air hose hooked to it. then there is another hole for a bolt, but thats it. i cant find anything that matches that thread pattern let alone matches & is hollow. i havent tried the center of a lamp yet, if you know what i mean. has anyone seen this set up before? signaltone was in Livonia, Mi but i havent found them in searching online. it looks like its supposed to be exterior mounted. thanks for any help. AXE

 

[Davids78Bronco]

I have the same sort of air horns you're talking about. the base has three screw holes, with the air supply thru the middle of it all, right? I used standard air fittings that I had laying around, to plumb mine. Mine is bolted to the underside of the Dodge's hood. I don't have the OBA on that one hooked up yet, but I did put a blast of air thru them... nice and loud! I've got a second pair, I'm thinking about adding

 

[axaviere]

yeah, thats kinda like mine. i just have one thru hole and one air supply. i went to the hardware store and i didnt find anything to even match the threads, which i thought was really weird. but i hit them with a blast from my compressor and i am thinking "what the hell am i using them cheap red plastics turds for" these babies are deep and loud too. i will try again at the hardware store. sweet deal. mine have a ford emblem on the top of the horns diaphragms.

 

[Dustball]

I don't know your knowledge of hardware and the method you're tyring to determine what thread size it is. You need to use pipe fittings to determine the thread size, not a standard bolt. NPT pipe threads are different than standard bolt NC and NF bolt threads.

 

[Davids78Bronco]

A brainfart came to me last night, and I suggested he try a tool repair shop, for the air fittings he's looking for