Weak 1931 Sparton Horn

[Tudor Tooter]

Hello, Ford Barn! I'm new to the forums and I'm hoping someone can help me with a Sparton Horn issue I have run into. But first, let me tell you a little about me. I'm 17 years and am proud to have lived in Dixieland all my life so far. My grandfather has a 1931/30 Ford Model A Tudor in Lombard Blue with French Grey rims that I take much interest in. The reason I say it is a 1931 AND a 1930 is because the drivetrain is a 30' and the body is a 31'. The restoration of the Tudor was completed in 1996 and the car has roughly 7500 miles on it now.

I don't have as much experience working on Model A's as I would like, but I figured I might as well start now. So far, I can drive my Grandfather's Model A quite fluently and troubleshoot to some extent. I have restored a Zenith-1 Carburetor that came off the car and have tinkered here and there with other parts.

So the bottom line is that I have a passion for Model A's and hope to restore and own many of my own in the future! But enough about me and my Grandad's car, let's get down to brass tacks.

For most of my lifetime, the Model A has ran and driven flawlessly. But in the past few years, the paint has chipped, and the performance quality has decreased, including the horn. The paint is acceptable as-is, and the rebuilding of the carburetor has fixed engine performance issues, but still some minor issues exist, such as the Sparton Horn. The Horn on this car hung in a barn for many years unused until my Grandad found it and bought it from a local man for a few dollars. All he did was put it on the car and it AHOOOOGA'd to life. Recently, though, it has weakened to a muffled purr. In fear of ruining the horn, I have not disassembled it past the horn cover. I tried lubricating with WD-40, but it still has a weak sound. The adjustment screw doesn't help- when I think I've got it at the right setting it's still weak. If I back it out too much, it doesn't hit, and if I screw it in too much, it doesn't move at all. It's definitely not a voltage issue because the Battery is fairly new. Any ideas on what could be the problem? A spring, perhaps?

Thanks for all your help! I promise all my posts won't be this long. I just figured I'd give a little background about myself so you guys would bear with my inexperience. Thanks again!

[700rpm]

Check the brushes for wear, and clean the commutator. Clean the grooves in the commutator with a wooden implement, not metal. Be careful with WD-40. A few drops of light oil at the front and the back of the main shaft is all the lubrication it should need.

Get a copy of the Ford Service Bulletins if you can, and study it well. A lot of typical service requirements are outlined there.

[mrtexas]

Take the cover off and sand the commutator bars with fine sandpaper, they are probably corroded. Soldering the electrical connection instead of using the push in type will also help. Oil the felts as well with light lubricating oil. WD 40 is water displacing oil.

[Tudor Tooter]

Thanks very much for the help! I'll look into that as soon as possible. It definitely looked corroded when I opened it up, and since it hasn't been serviced in who knows how many years, I'm guessing that corrosion or wear on the brushes is the issue. Thanks again!

[Bob C]

Just because the battery is good don't assume you don't have electrical problems.
A bad ground or loose connection could be part of your problem.

Bob

[700rpm]

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If that's the car in your avatar, it looks like you've got a good one. Welcome to the hobby. It will likely become part of your life. I got my first A when I was 16; that was 50 years ago.

[Tudor Tooter]

That's it! The car pictured is my Grandad's. I'm definitely sure it will be a life-long hobby. I would get one to drive around in College, but I'm scared it would get dented and scratched up by other kids with their brand new Mustangs and Camaros. Maybe I would have nothing to worry about, seeing as that all the new cars are made of plastic. I was told a story of a man who hit a metal power pole at 35MPH in a Model A. It killed him instantly on impact, but the only damage the Model A recieved was a bend in the shape of the pole on the bumper. They are tougher than they look, that's for sure!

[Tudor Tooter]

Back to the horn, I ordered a brush & spring set from Snyder's... I figured since they were only $2.60, I might as well replace them anyway. How do I need to replace the brushes? Is it just a matter of unscrewing the old ones and putting new ones on or is it difficult? If it requires dis-assembly of the entire horn, I might need to re-think the situation.

[1931 flamingo]

You ned to get a copy of Les Andrew's model A book. JMO Have no experience with the horn other than lubing it.
Paul in CT

[jkeesey]

As a quick try hold a catch pan under the horn, remove the back and soak it in brakleen. If possible do it running but it ca get messy so make sure any important paint is covered. And deadjust the horn first so the motor will spin free. Oil tends to slow down electric motors. If she spins nice and fast put the cover back on and try to adjust it. As a preliminary run the horn with the rear cover off and deadjusted and see how fast it goes

[Tom Wesenberg]

Originally Posted by Tudor Tooter

Back to the horn, I ordered a brush & spring set from Snyder's... I figured since they were only $2.60, I might as well replace them anyway. How do I need to replace the brushes? Is it just a matter of unscrewing the old ones and putting new ones on or is it difficult? If it requires dis-assembly of the entire horn, I might need to re-think the situation.

I would never replace any part just because the replacement part is cheap. You might actually be adding another problem to the mix. Remember, original parts are almost always the best quality parts, so they should only be replaced when they are beyond being useful or not rebuildable.

I fixed a slugish horn for a friend by holding fine sandpaper against the commutator as he held the horn button down. The armature was spinning slow at first, but started picking up speed as the sandpaper cleaned the armature. After about one minute of this his horn now blows better than mine.

A clean armature and oil on the two wicks is a big help for most horns. Also make sure the final adjustment is made after the cover is screwed on because the pull of the cover screw on the rear of the motor frame can change the armature adjustment.

[Tudor Tooter]

Sorry about the delay in response. I will definitely check into finding a Les Andrews book, but $62 for a used paperback seems steep to me. Maybe I'll ask for one for Christmas! I think I might use it enough to justify the cost, but I'm going to look around a little bit before I pay that much on eBay.

I'm a little sceptical about using brakeleen on the horn... Are you sure that won't damage the motor? I don't mean to insult your intelligence, I just try and be as careful as possible because the car isn't mine.

I'll definitely try the sandpaper. Is 400 grit about right? What oil would y'all use? Is PB Blaster OK in small quantities? I now know not to use WD-40.

[700rpm]

$62 used??? Les Andrews' "Model A Ford Mechanics Handbook, Vol. I" is advertised from MAFCA for $35.00 new. That's the only volume you'll need to start out with. A paperback version of the Service Bulletins is available on Amazon for about $25. You can get that later, but get it for sure.

[1931 flamingo]

Tudor Tooter: Where are you located, there may be someone close by who could give you a hand?
paul in CT

[Tom Wesenberg]

Regular motor oil is fine to oil the wicks. A couple drops on the rear wick is enough. You want the oil to lubricate the shaft, but not creep onto the commutator. Notice how the brushes look like a compressed brass screen. If these are oil soaked then I'd use some gas and compressed air to clean them. An eye dropper or small paint brush will work to get the gas onto the brushes to clean them. If you remove the brushes to clean them or change them or their springs, take note of the two insulating washers used to hold the brush holder in place. One washer on each side of the motor frame for each brush. Also make sure the brush slides nicely in it's holder. The last horn I worked on had a bent brush holder from someone using too long a screw for the horn cover. The holder was bent so bad that the brush was locked in place.

[Tudor Tooter]

I live in Anderson, SC, but my Grandad (& the car) live near Florence in SC. That's why I'm trying to figure out how to fix everything before I go for a visit in 2 weeks. Currently, the two things I'm focusing on when I go visit is the installation of the carburetor I rebuilt, and the fixing of the horn. I think, maybe if I had some pictures that were labeled, I would do OK.

[Bruce Lancaster]

Before you do ANYTHING, isolate the horn to be sure the problem isn't external: Unplug the two wire connectors, ground one solidly and hook the other to battery post or connection at starter. You might be very surprised...a good horn will practically knock you out of your socks.
To accomplish, make a couple of improvised tools you can use for the rest of your life:
Get two 3 or 4 foot lengths of maybe 16 gauge automotive wire, put an alligator clip at each end. I like a claw-looking type at one end (bigger bite span) and an actual alligator at the other, and wires should be different colors so you always know which one is to ground and which is hot. While at the parts rack, get a bulb socket and find it one 6V bulb (borrow from the taillight!) and get a 12 too for other uses. Solder on a ground wire and hot wire also with clips.
Obviously, the first two are used to hook up horn without vehicle wiring/switch in the circuit.
The second can be used to determine if any circuit is actually providing electricity and will also actually give a bit of further information: Once you are familiar with how the bulb shines, you will note a distinct drop in brightness if you have a poor circuit... the 6v drops off fast if you have resistance from a poor connection.

[Tudor Tooter]

Below is a zipped folder with an MP3 of the horn in it. It's only 3 or 4 seconds long, so it doesn't take long to listen to it or download it. This was recorded just a few months ago and it still sounds like that now. I figured if y'all could hear it, you might could diagnose it more easily.

Model A Horn.zip

You may need software that can unzip the file.

[RcT]

Just a few words of advise from someone who has been there... go slow and read everything you can, on-line and books, and learn what you are attempting to fix. Many times it's a matter of cleaning, oil, adjustments or whatever, without buying repo parts. There's a lot of experience here that's free for the asking. Good folks. Don't order parts until you know that is absolutely the problem... or end up with boxes of stuff you will never use. Try to find original parts if you can and if affordable. Get your parts from reputable parts houses. Probably the best advice I got from my dad about 50 years ago, was to work on one thing at a time, then try it out and check your work. If you work on the carburetor, don't mess with the electrical, because if it won't start, you won't know why. Welcome to the hobby and have fun.

Richard

[JBR]

Use 600 sandpaper. Not Wet or Dry. When I did mine I started with 600, went to, 1000, and finished with 1500. It got better each time.

Can you send me an email address?
Jon.