fixing air horns

[grasshopper]

Is there a way to get air horns working again ? What makes them stop working ?

[v6spider]

Check to see if the pump is getting power when the horn button is depressed.. If it is then the pump is bad.. Other wise, if you don't have power check the horn button circuit and the relay that sends power to the pump.. Also check grounds and fuse box.. Corrosion is the enemy make sure all connections are shiny clean and tight..

Rob

[grasshopper]

I was talking about the actual trumpets,,,no sound is coming out,,,

[v6spider]

Check to see if the pump is pumping air.. Could be running but no air output. Also, check the air lines for leaks and obstructions.. If all checks or good there.. Then the air horns may need adjustment.. There's a lock nut at the base of each horn. Loosen the nut and then you can either tighten or loosen the horn to adjust for sound output.. If they are Corroded inside I've had success reviving them by squirting wd40 in them and blowing them out with compressed air..

Hope this helps,
Rob

[azruss]

[grasshopper]

Thanks for all this great info.

[v6spider]

Thanks for all this great info.

My pleasure. And great pictorial too on clean up and overhaul of the air pump by Azruss!

Thanks!
Rob

[DieselSpider]

It is important that you DO NOT use an Aluminum Oxide sand paper on the commutator. It has the potential to short circuit things and set up a corrosive reaction with the copper. After you blow out all the dust from the carbon brushes its not a bad idea to lightly renew the lacquer on the copper windings being sure to keep the commutator and bearing areas wrapped with rags to keep the over spray off of them. Just don't go too heavy or you can throw it out of balance.

[grasshopper]

Is it possible to take the actual horns apart ? I know that you can screw off the trumpet,but how do you pry apart the round part ?

[azruss]

careful about screwing with the horns. there is a large plastic cap on the back and the bell itself can be unscrewed. I see no advantage to trying to separate the diaphragm section. There is a very specific tolerance between the horn and the diaphragm. If that isn't quite right, then the horn doesn't sound or you get no volume. It can be adjusted by blowing very low air pressure into the horn while you attempt to tune it. Warning!!! Even with proper ear protection, this is a good way to go deaf.

[DieselSpider]

At $15 the twin horn kit from Harbor Freight makes it not worth the bother for many folks.

http://www.harborfreight.com/automotive ... 40134.html

Some recommend adding a few drops of Super Glue where the trumpets attach.

First verify that the compressor on your horns is actually putting out enough air to activate them before going too crazy taking stuff apart. You can hook them up to your shop compressor and slowly up the pressure until they sound in order to test them.

[v6spider]

It's sooooooo easy to tune the horns with them removed.. Using an air compressor.. Just 10 to 20 psi is all you need to fire them once they are tuned. Again wd40 in the horn orifice and air inlet work wonders. The horn won't be able to sound until you blow out all the wd40 ..And yes by All means don't go deaf. Wear ear plugs..Lol

Cheers!
Rob

[btoran]

My air horn recently stopped working. Although I could hear the relay click when i hit the horn button, no sound was coming out. I was given some advice to squirt a little oil into the compressor (there's a small red cap on the top of mine). That did the trick. Your issue may be different, but if it's the same, it's a FAST, CHEAP fix.

[seabeelt]

AWESOME tutorial!!! I believe RoyBatty replaced the alum flap in one of his trumpets to get it to work, or might have been someone else, but they can be repaired.
R/

[azruss]

as a side note; i have horns from a 69,70,71,75 spider and coupe. I have 3 different horn lengths. the short horns are all the same, but the long horns are 2 different sizes giving a 1/2 tone pitch separation with the short one and a whole tone with the other.