Sick Ahh-Ooh-Gah

29Cabriolet

29Cabriolet

Senior Member
The title should suggest where I am going with this post. My horn kind of sounds Ahh-Ooh-Gah, but is barely audible. When on the road and RPMs are up of course it's a bit louder but still quite weak. Would this seem to be a problem with the horn itself or more likely an electrical problem or deficiency? I am still 6V with stock generator, no voltage regulator or other "modernization" add-ons. Suggestions?

Thanks!
 
The first thing I would do would be to take the back cover off the horn, clean everything up then lube it with a light oil or as I prefer, a teflon spray lubricant. Mine was acting the same way and after doing this it now works and sounds like new. Good luck
 
While you are in there doing what Standing Elk suggested, try grounding out the wire from the horn switch directly to a good ground point on the chassis. This might help determine if the problem is in the horn itself or in the horn button/wiring.
 
some other ideas
 

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cpf240 said:
While you are in there doing what Standing Elk suggested, try grounding out the wire from the horn switch directly to a good ground point on the chassis. This might help determine if the problem is in the horn itself or in the horn button/wiring.
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I'm not so sure about "grounding out" that wire! The retention screw fell out of my horn (pulling out wires) which, in turn, grounded out killing the engine (in traffic!) Engine wouldn't re-start, discovered fuse had blown when it grounded out!

Until this happened, I didn't know screw had fallen out. Luckily, back was not lost too.

Since that occurrence, I have been trying to adjust horn to sound correct again (with no luck as of yet.)

Bill
 
BillEbob said:
I'm not so sure about "grounding out" that wire! The retention screw fell out of my horn (pulling out wires) which, in turn, grounded out killing the engine (in traffic!) Engine wouldn't re-start, discovered fuse had blown when it grounded out!

Until this happened, I didn't know screw had fallen out. Luckily, back was not lost too.

Since that occurrence, I have been trying to adjust horn to sound correct again (with no luck as of yet.)

Bill
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Just to be clear, I meant grounding out the wire that come from the horn button in the headlight switch assembly, as that is what the horn button is doing, providing a ground path. The other wire to the horn is hot at all times, and shorting it out could very well blow the fuse and/or kill the engine.
 
Check brushes for free travel. Springs get weak after 90 yrs. Sand armature contacts with fine grit & clean grooves with a toothpick. Horn relay usually solves weak horn button contact.

The yellow wire is the hot one, directly off the generator.
 
Try this. Get someone to push on the horn button while you back off the adjustment. Let the horn motor run up to speed for about a minute. It’s good for the motor to run. Then adjust it and it should sound better.
 
Badpuppy said:
Check brushes for free travel. Springs get weak after 90 yrs. Sand armature contacts with fine grit & clean grooves with a toothpick. Horn relay usually solves weak horn button contact.

I found that brake cleaner will make the armature contacts look like new without sanding. Also cleans up the whole area. Let completely evaporate before hitting the horn button :eek: or use the non-flammable type.

John
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Never heard of using brake cleaner for electrical contacts. Good to know, I"ll have to try it (after pulling the fuse). JacksonIII's idea is a good one too.
 
When the horns on my Model A’s get lethargic, all I do is to remove the covers and spray the brushes/armatures with non-flammable electric cleaner while the armatures are spinning. Then I lightly oil the bearings and put the covers back on. I need to do this about every three years or so.
Robert
 
You Tube...Type in Model A horn"
Never had a resource like that when I was young. We would ask each other how to fix it and the guy that was the most convincing we listened to. Kinda like voting. Chap
 
Badpuppy said:
Never heard of using brake cleaner for electrical contacts. Good to know, I"ll have to try it (after pulling the fuse). JacksonIII's idea is a good one too.
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Or could just use electrical parts cleaner. I'm not sure what the difference is. Both are likely formulated to leave little to zero residue and evaporate quickly.
 
Be careful using brake cleaner (it's also will ruing any paint that it comes in contact with). Try using electrical contact cleaner on the brushes & armature it's what it is designed for.
Bob
 
JBill said:
Or could just use electrical parts cleaner. I'm not sure what the difference is. Both are likely formulated to leave little to zero residue and evaporate quickly.
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Bob Wright said:
Be careful using brake cleaner (it's also will ruing any paint that it comes in contact with). Try using electrical contact cleaner on the brushes & armature it's what it is designed for.
Bob
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WD-40 it is!:D
 
I had the same problem with my horn and did most of the cleaning/adjustments mentioned. Ultimately found the generator was not charging enough so the horn got enough juice to go OOOO but not GAAAA. An adjustment of the third brush in the gennie solved the problem.

Glen
 
It's amazing to me just how much juice it takes for the Model-A horn to work!:eek: I'm thinking it takes just as much if not more then the starter?!?:confused: But, what do I know, I also own a Chevrolet...:p:rolleyes:;)

Bob-A:D
 
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