What goes wrong with air horns?

[Jim Stoltz]

The air horns on the Allegro stopped working. Not the fake electric ones up top, but a pair installed by the previous owner in the grille. I have plenty of air pressure, the solenoid works and I can hear the air whooshing through the horns but no horn sound. At least that I can hear. The sound they make is so high pitched that every dog in the neighborhood goes nuts.

I assume there's some sort of diaphragm for each horn, but could both fail at the same time? Maybe one has always been bad and now the other has gone? What goes wrong with these things.

[Rick Faunce]

Could be that the solenoid is clogged and not enough volume of air is moving through. Take the line off the solenoid to the horns and blow into them with your home compressor and a blow gun and see if the horns work that way. Are you sure your roof horns are electric? Mine are air.

[Jim Stoltz]

Thanks Rich. Roof horns are definitely electric. They look like air horns but they're not. The PO installed real air horns behind the grille, which functioned fine until a couple of days ago. I'll blow out the solenoid and see if that works.

Now that I think about it, the reason the roof ones don't work is probably because they were disconnected in favor of the ones behind the grill. I'll have to look into that. Either way, they only have wires running to them - no air.

[Lakota Wolf]

Dirt and crud get swept in there and the diverter gets bunker up. I have to take mine apart and clean the passageways about 2 to 3 times a year. They are actual 155 db air horns with 100 p.s.i. behind them. Electric ones the vibrating disc get gummed up or worn and the adjustment screw needs adjusting.

[Jim Stoltz]

I blew air right from my big air compressor into them last night and they still don't work. I'll have to take them apart and see what's up. These say max 150 psi - I have the compressor cycle on at 110. It shares the compressor with the air-ride suspension but it never gets less than 90 psi. Most will work between 40 and 150.

[Lakota Wolf]

Do you have an on board air tank? You need one for air horns cuz direct air off suspension pump won't supply the demand.

[Jim Stoltz]

I do have an onboard tank. Looks to be 5 gallons. The horns and the air suspension share it. I ordered up new horns. Couldn't get the old ones apart.

[Lakota Wolf]

They probably needed changed anyway with new shiny chrome ones.

[Rick Faunce]

You have to be somewhat careful with horns and suspension on the same 5 gallon tank. Horns use a LOT of air fast. Chances are you are not laying into the horn and staying there but if you ever do you could drop a five gallon tank down to 40-50 lbs. in ten seconds! Maybe longer assuming you are running 1/4" tubing but it will go fast and then the compressor has to work extra hard to play catch up. Short blasts are no problem at all though. It would pay to add another compressor and tank just for the horns and maybe for things like blow up toys and tire inflation. That way you are not stressing a component that is really needed for driving. Not to mention you would have a spare already online if the suspension compressor failed. If it fails you will sit right down on the bumper eventually. I am going to put my second one in this winter and tie it into the original suspension lines with a one way valve. That way even if I have a tank failure on the suspension system all I have to do is turn a valve and it will feed from the other tank and compressor bypassing the original tank. I like redundancy, what can I say?

[Lakota Wolf]

Thats true,,,, you should have an air tank, just for the air horns,, not tied in with suspension,,, I have an 8 gallon for air horns with direct air pump and 2 spares which come in handy when ya need to air up a tire or mattress. With an 8 gallon I can get several short bursts or a good 45 second continuous, then I need to replemish the air tank supply,,,, Horns take a lot real fast.

[Jim Stoltz]

Yep. Got a 3 trumpet setup.

[Jim Stoltz]

It's a big compressor - I installed it myself. The original Jet Air pump was shot. The previous owner teed off the air pressure gauge for the horns. I very rarely need to adjust the bags - only when going up and down my driveway. They never compete for air with the horns. The bags are isolated with solenoids so pressure in the tank doesn't affect them. I bottomed out once and tore the drain valve off of the air tank, emptying it immediately. It maintained its ride height no problem. I did switch it to manual just in case the system tried to adjust the height with no air pressure. That would have been bad.

[Rick Faunce]

Just so you know that system is constantly adjusting while you are driving.