Post War Texas Special Horn won't Stop!!!

Hi Kenny. I just saw the post. I just replaced a relay in my Santa Fe 2353. Look at the contacts of the relay and make sure that there is a gap. If there is not a gap then gently bend one of the contacts until they are separated. Power up the horn and make sure that the coil works on the relay.

Yes, sometimes the metal plate on the bottom of the relay becomes magnetized, and then it doesn't disengage. Some people fix this with tape, or hitting it with a hammer.

Bottom of relay is armature plate if it blows continuously you can use emery cloth to sparingly shine the contact points the  top and bottom one then with toothpick gently push upwards on bottom plate sometimes they get darkened and stick to each other.

You want the plate to drop back down by itself when gently closing the contact points.

See what happens if that fails to help then give a very slight upwards bend to top contact" very slightly "and apply power. See if they still stick.

 

Last resort

there is also a copper spring strip under the bottom plate and its the back portion that can be very gently bent "gently" that will force the plate to drop down or stay in closed position.

Good luck.

Many times I have run into the horn relay contacts becoming pitted and they stick closed.  The contacts on the relay are fairly small and you have to be careful what you clean them with.  I purchased a relay contact polisher from an electronics store.  It is a small, thin device with polishing surface.  If you use something too rough and put scratches in the contact surface they will have a tendency to stick even more.  If this doesn't work I just replace the horn relay with a new one.

 

The other troubleshooting suggestions made above are all typical of this relay.

 

Steve, Lady and Tex

Michael R.,

You are correct!

The number one tool, to fix anything, is a 'HAMMER!'

My father would always say for repairs use a hammer!

BUT, it depended on how angry a person got with a malfunctioning item, in need of repair.

Ralph

 

If the hammer effect does not work, you can always get a BIGGER HAMMER!  

While placing the engine upside down to insert the battery, the relay contacts will close by gravity, and the horn will start to blow as you close the cover. It should stop when you turn the engine upright.
If the horn continues to blow, either the relay contacts are stuck closed, or you have a short.
If the relay contacts are not stuck closed, look carefully at the wire leading to the horn itself. Check to see whether a bare portion of the wire is touching one of the other terminals, or the metal body of the relay or the battery bracket.

If the relay contacts are stuck closed, then look to see whether there is something underneath the armature or contact that is holding it closed. Perhaps the previous owner bent the contact upward, and now it cannot move away from the fixed (non-moving) contact.

Left undisturbed, I find that the contacts themselves rarely need adjusting. But often things come my way that have been "fixed" before.

There are some good suggestions above - I'll add some thoughts as to what's worked (and not worked) for me when I've worked on horn and whistle relays.  I've probably worked on fifty or so in the last 20 years, and almost all of them worked after a careful cleaning and occasional demagnetizing.  

 

Check the wiring - look for insulation that's crumbled, or oversized globs of solder on the wiring on the top of the relay.  If you have a similar engine with the same relay, compare them, check to see that the wiring is identical, and make sure that the solder tabs on the top of the relay are spaced apart correctly and aren't touching each other.  

 

Get some CRC electric contact cleaner (plastic compatible version) and a stiff piece of paper (the fancy stuff for resumes works well).  Spray some contact cleaner on the corner of the paper, you don't need a lot.  Spray a shot of cleaner on the arm/contact tab as well.  Insert the soaked edge of paper in between the relay contact and the arm that lifts, GENTLY push the arm up until you feel it making contact, and then CAREFULLY slide the paper side to side.  You'll probably see a little blackish discoloration come off on the paper.  Repeat until the paper soaked with contact cleaner doesn't show more black coming off.  Go to the back side - at the botom corners are tiny copper tabs that flex.  Use the contact cleaner-on-paper routine at the copper contact areas.  GENTLY AND CAREFULLY slide the paper  between the contact areas.  It's a good idea to clean those contact points, even if it turns out that your relay is magnetized - 50 years of corrosion/dirt has built up, and a good cleaning is going to help your horn work at its best.

 

The suggestion that the relay might have become magnetized is also a good possibility.  You can try demagnetizing it with a rap from a hammer - again, do this CAREFULLY - you don't need to wallop the relay, just give it a good tap.  If you've got access to an old hand held tape deck head demagnetizer, you can also try demagnetizing the relay that way.  Plug in the demagnetizer, slowly bring it towards the relay, hold it there for a few seconds, and then slowly bach the demagnetizer away from the relay.  Don't shut the demagnetizer off while it's close to the relay, or you'll end up making the relay more magnetic than when you started.

 

Try to avoid bending any of the contact points or arm on the front unless you can see that someone has bent them and they don't come apart/lift the right way - unless you've worked on relays several times (and probably wrecked one or two along the way), it's best to not make physical adjustment unless you've tried the other steps first.  Relays tend to be $20 - $35 dollars when you find them on Ebay, and you can probably get your relay to operate if you work carefully and make as few physical changes as possible.  I'd also recommend not using anything abrasive to clean the contacts - you want those areas to be as smooth as possible as the little scratches in the metal you leave behind are an invitation for corrosion/dirt to build up in the microscopic grooves.

Thank you for your insight on the #2245 horn.The contacts are not closed,I have some type of short.I've fixed hundreds of these before,but the problem always was the horn would not sound.This one sounds strong and has a fantastic tone,I just can't get it to stop unless I take the battery out!!!!!

I like the hammer idea.I purposely stopped working on it,because it was giving me shingles.HAMMER TIME

       
       
The contacts are not shut in the closed position,the unit goes up and down upon command from the transformer.So the problem is somewhere else .Thanks for your reply

       
       
The plate works perfect.It is not touching anything except when you press horn button.It then goes up,and drops back down like it should.So It is something else.I've gotta look at this again,I got the shingles trying to fix it last time,so I sat it aside ,which is very uncharacteristic of me.The train is just so fine,I did not wanna take out my flustration on it.Whole chassis looks not to be altered at all from factory.

Check the wires on the relay. Small bars of insulation separate them. Make certain that each is insulated from the others. Worn insulation could allow two wires to touch on the relay or maybe farther away.

 

A problem like this one can be tricky. Just be patient.

Follow the wire from the positive battery terminal to the relay, and follow the wire from the horn to the relay. They should not be touching, and should be soldered to separate contacts of the relay.

 

Larry

I've used the hammer method for magnetized relays. Sometimes it works, sometimes not. When it doesn't, I put a piece of Scotch tape on the armature plate. That always works.

 

Roger