Adjusting ahooga horn

mngreen

Senior Member
I can only get my Stewart horn to sound correctly with the motor cover off or with the cover on with the hold down screw put on very lightly.

Any suggestions? :confused:
 
When I adjust the horn I always make the final adjustment after the cover is screwed on. The cover tension will pull on the frame a bit, so I often have to turn the adjustment screw one click. Also the original cover screw is only threaded enough to hold the cover in place. Repro screws have enough threads to screw them on too far is you tighten too much.
 
Thoroughly clean the commutator/armature contacts with very fine sandpaper. Also the two wire connections at the base if they are the clip in type or similar.
As said above, adjust with the cover on.
 
...the original cover screw is only threaded enough to hold the cover in place. Repro screws have enough threads to screw them on too far is you tighten too much.

Thanks for bringing this up. In fact, the cover screw on my Stewart Warner is threaded all the way causing me it to over-tighten. I got to thinking and came up with the following bright idea, absent an original cover screw, of course. :D

I dug up a nut to function as a "stop position" on the screw. I inserted the screw through the cover and put on the nut at different positions until I got the screw to tighten against the horn frame while not letting the cover bind on the housing. After doing the above, my horn sounds a lot better, but not perfect. (One note: it is very easy to short out the horn with the nut assembly described if you are not careful--I did so and saw smoke! Luckily, my main 30A fuse at the starter junction blew to save the day) :o

How hard is it to find an original designed screw for the job?
 
Thanks for bringing this up. In fact, the cover screw on my Stewart Warner is threaded all the way causing me it to over-tighten. I got to thinking and came up with the following bright idea, absent an original cover screw, of course. :D

I dug up a nut to function as a "stop position" on the screw. I inserted the screw through the cover and put on the nut at different positions until I got the screw to tighten against the horn frame while not letting the cover bind on the housing. After doing the above, my horn sounds a lot better, but not perfect. (One note: it is very easy to short out the horn with the nut assembly described if you are not careful--I did so and saw smoke! Luckily, my main 30A fuse at the starter junction blew to save the day) :o

How hard is it to find an original designed screw for the job?

Easy. Any good Model A supplier will have them. About $1.50, I think.
 
If you look closely at the brush holder on the left, you can see a circle where a repro screw was run into it until it bent the side of the brush holder and locked the brush in place.
 

Attachments

  • Sparton Horn Repair.jpg
    Sparton Horn Repair.jpg
    59.5 KB · Views: 246
Here's a picture of an original cover screw. Also note how the wire terminals plug in from the ends of the clips, and not under the sides. Also note the felt washer that fits around the adjustment screw before the cover goes on.
 

Attachments

  • Horn Cover Screw.jpg
    Horn Cover Screw.jpg
    54.6 KB · Views: 255
Here's a picture of an original cover screw. Also note how the wire terminals plug in from the ends of the clips, and not under the sides. Also note the felt washer that fits around the adjustment screw before the cover goes on.

Thanks Tom. Now I'm going to have o go out and look at my adjusting screws. :rolleyes:
 
Ahhhhh ................................felt washer. ! ! ! !

I wonder how many horns out there DON'T have the felt washer??
Source for the felt washer?? Snyder's doesn't show one.
Paul in CT
 
OK< felt washer not shown in pic above, nor in snyder's catalog. It looks like it's shown in mac's new catalog.

How important/effective is it?? Do I really need one?? SOURCE??
Paul in CT
 
Paul,

It is labeled in the 2nd drawing as a dust felt. The dust felt helps to keep the inside of the horn clean. It is placed over the screw and between the cover and the adjusting bar creating a seal which prevents the dirt from entering the horn. I live on a dirt road and it helps.

Paul
 
I had to add a aground to my horn. In fact, I have added a separate ground for each of the lights. Finally, I added a ground from the engine to the frame.
 
Back
Top