Visit our BAC Favorite Places Web Page

Author Topic: Air horn issue  (Read 668 times)

Al Lewis

  • BAC Member
  • *
  • Posts: 78
  • Thanked: 15 times
Air horn issue
« on: March 19, 2019, 11:33:32 PM »
My air horns will not work unless the air pressure is low, like 100 psi. Does anyone know where the air valve is located so I can troubleshoot/replace the device. 2002 Monterey.

Thanks
« Last Edit: March 20, 2019, 02:17:32 AM by Steve Huber Co-Admin »
2002 Monterey, Cumins ISC 350, Texas

David T. Richelderfer

  • David, Leslie & JB
  • BAC Member
  • *
  • Posts: 1106
  • Thanked: 303 times
  • 2004 Marquis Sapphire 45, 505 hp C-12
Re: Air horn issue
« Reply #1 on: March 20, 2019, 01:14:13 AM »
In our coach, the solenoid-air valve that actuates the air horns is located in the electrical bay - fore basement door, driver's side, under the driver's seat - located on the inner wall near the compartment floor.  I changed out the solenoid-air valve a few years ago after it got hot, partially melted, and discontinued functioning.
« Last Edit: March 20, 2019, 02:17:49 AM by Steve Huber Co-Admin »
David, Leslie & JB
Towing a black Chevy Avalanche
Using a Blackhawk Towbar & Evenbrake
RF Mogul Eagle 3 for DISH TV
Go Beavers, OSU Class of '71
RVing since 1973
Constitutionalists, Golfers & Capitalists
Your luck is the residue of your management

Gerald Farris

  • Past President
  • Board Moderator
  • *
  • Posts: 2017
  • Thanked: 721 times
    • Farris Journey Across The USA
Re: Air horn issue
« Reply #2 on: March 20, 2019, 03:57:44 PM »
Al,
The air horn solenoid valve is in the LF electrical bay on almost all Beaver coaches.

David,
About the only reason that the air horn solenoid valve will over heat is when it is engaged for a long period of time like if someone sets something on the steering wheel horn button when the steering wheel is in the upright position when parked. If this happens when you have no air pressure, the horn will no sound but the solenoid will engage until it destroys itself.

Gerald
2002 Solitaire (2017 -  )
2000 Marquis, C12 (2004 - 2017)
1993 Patriot  (2000-2004)
The following users thanked this post: Stan Simpson

David T. Richelderfer

  • David, Leslie & JB
  • BAC Member
  • *
  • Posts: 1106
  • Thanked: 303 times
  • 2004 Marquis Sapphire 45, 505 hp C-12
Re: Air horn issue
« Reply #3 on: March 20, 2019, 05:03:37 PM »
Gerald - That was my thought too.  I rarely use the air horns.  I occasionally use the air horns to get the attention of my outside spotter when backing up the coach.  I was thinking perhaps some water came down the air line from the roof and got into the solenoid air valve.  In recent times, if we will be parked for a week or more, then we position the computer printer on the upright placed steering wheel - a convenient height and out of the way... but not such that it presses on the horn bar.
David, Leslie & JB
Towing a black Chevy Avalanche
Using a Blackhawk Towbar & Evenbrake
RF Mogul Eagle 3 for DISH TV
Go Beavers, OSU Class of '71
RVing since 1973
Constitutionalists, Golfers & Capitalists
Your luck is the residue of your management
The following users thanked this post: Stan Simpson

Gerald Farris

  • Past President
  • Board Moderator
  • *
  • Posts: 2017
  • Thanked: 721 times
    • Farris Journey Across The USA
Re: Air horn issue
« Reply #4 on: March 20, 2019, 05:26:44 PM »
David,
Water in the air line from the air horns should not cause the over heat problem, but it can cause the air horn solenoid to become inoperative due to corrosion. Overheating the solenoid is caused by a completed electrical circuit that water in the air line can not accomplish. It is virtually always something on the horn bar or a short to ground in the steering column.

Gerald
2002 Solitaire (2017 -  )
2000 Marquis, C12 (2004 - 2017)
1993 Patriot  (2000-2004)
The following users thanked this post: Stan Simpson

Al Lewis

  • BAC Member
  • *
  • Posts: 78
  • Thanked: 15 times
Re: Air horn issue
« Reply #5 on: March 21, 2019, 04:42:40 PM »
Ok, I found it. Thanks for the direction. The writing on the device was covered by the hold down strap. It does say it is for air horns. I was misled by a larger more complex air device below it. But when I disconnected the wires, the horn would still honk. Any idea what it does?

I need to measure the voltage to see if it could be low. If ok, then get on with finding a replacement.
2002 Monterey, Cumins ISC 350, Texas

Gerald Farris

  • Past President
  • Board Moderator
  • *
  • Posts: 2017
  • Thanked: 721 times
    • Farris Journey Across The USA
Re: Air horn issue
« Reply #6 on: March 22, 2019, 04:00:28 PM »
Al,
The air horn solenoid valve has power at all times and it is activated when the horn button completes the circuit by furnishing a ground. The most common problem with this valve is corrosion, especially with roof mounted air horns that let water drain down to the valve. You can some times take the valve off, and spray a good penetrant into the ports, tap it on a bench, and activate it a few times to get it working again. If you are getting water in the valve, you can blow the horn on a regular basis, especially after driving in a rain, and this will keep the valve clear and prevent corrosion.

Gerald
2002 Solitaire (2017 -  )
2000 Marquis, C12 (2004 - 2017)
1993 Patriot  (2000-2004)

Al Lewis

  • BAC Member
  • *
  • Posts: 78
  • Thanked: 15 times
Re: Air horn issue
« Reply #7 on: March 22, 2019, 05:24:34 PM »
Gerald

Interesting info. Yes my horns are on the roof and they get operated very rarely. The valve is not stuck but needs a good 12 volts to operate when the air pressure is 130. I measure 1.7 volts to ground across the grounding horn button switch. Current is 3 amps. A direct ground would sound the horn and 130 psi with the diesel not running. With the diesel running providing more source voltage the horn will sound at least today using the horn button.

My question is, would you buy a new valve, or take it off and try to limber it up?  Another option would be looking for resistance in the ground circuit but that might be a lot of work.
2002 Monterey, Cumins ISC 350, Texas

Gerald Farris

  • Past President
  • Board Moderator
  • *
  • Posts: 2017
  • Thanked: 721 times
    • Farris Journey Across The USA
Re: Air horn issue
« Reply #8 on: March 22, 2019, 10:14:49 PM »
Al,
It does not cost anything but a few minutes of your time to try to free up the valve a little, so that is the way I would go. If that does not help, you can always replace the valve later.

Gerald
2002 Solitaire (2017 -  )
2000 Marquis, C12 (2004 - 2017)
1993 Patriot  (2000-2004)

Al Lewis

  • BAC Member
  • *
  • Posts: 78
  • Thanked: 15 times
Re: Air horn issue
« Reply #9 on: March 23, 2019, 06:16:55 PM »
Gerald

Ok, I lubed and exercised the valve and it will now honk at 130 psi and with the Diesel engine off. We will see how long it lasts. I am always impressed with the vast knowledge you have made f these motor homes. You must have made a living doing this at one time. To me it is just an interesting challenging hobby. I have been fixing mine for 15 years but there is always something I have not worked on.

FYI--I have had a problem getting a Texas safety inspection in recent years because of the air horn. I got tired of arguing with them and added a beep beep city horn and another button. Now they are happy but I am too embarrassed to use it on the road.

I will try to exercise the air horns more often.

Thanks again.

Al
2002 Monterey, Cumins ISC 350, Texas

Dwight Lakusta

  • BAC Member
  • *
  • Posts: 78
  • Thanked: 9 times
  • 2003 Marquis Ruby, C-12, 505HP
Re: Air horn issue
« Reply #10 on: March 25, 2019, 04:40:19 AM »
Gerald

Ok, I lubed and exercised the valve and it will now honk at 130 psi and with the Diesel engine off. We will see how long it lasts. I am always impressed with the vast knowledge you have made f these motor homes. You must have made a living doing this at one time. To me it is just an interesting challenging hobby. I have been fixing mine for 15 years but there is always something I have not worked on.

FYI--I have had a problem getting a Texas safety inspection in recent years because of the air horn. I got tired of arguing with them and added a beep beep city horn and another button. Now they are happy but I am too embarrassed to use it on the road.

I will try to exercise the air horns more often.

Thanks again.

Al

What did you use for lubricant if you don’t mind me asking? I have a similar issue. My horn comes on for one second and then runs out of air.... maybe similar issue?
2003 Beaver Marquis Ruby 40, 3 slides, C12, 505HP. Current unit.
2008 Newmar Dutch Star, 40, 4 slides, 8.9 ISL, 400HP.
2000 Monaco Windsor, 40, 2 slide, 8.3 ISC, 330HP.

Al Lewis

  • BAC Member
  • *
  • Posts: 78
  • Thanked: 15 times
Re: Air horn issue
« Reply #11 on: March 27, 2019, 09:05:07 PM »
I used carb cleaner first. Then followed up with liquid wrench. Just what I had in the shop. Your problem sounds different but I don't know. I would suspect a pinched line far enough back in the line such that the pressured line was enough to give a short blast.
2002 Monterey, Cumins ISC 350, Texas