# Lionel 2338 Horn headaches!!!



## rgodin (Jan 11, 2013)

Bought a used 2338, cleaned it up (LOF) put it on the track and the horn gave a low buzz (engine runs great). I tried to adjust but no better luck. So, I bought a new horn. It still won't work but accidentally touched the horn connection on the relay and the relay frame with a screw driver and presto, the horn works. Seems to be a short somewhere but I have traced all the wires with the wiring diagram (I am not finding any obvious shorts), short of pulling everything apart could someone please tell me where to start looking or how I might isolate the problem short of tearing it all apart. Also, when I push the whistle button on the transformer, the lights get brighter and the engine speeds up!
Thanks much in advance,
Ron


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## servoguy (Jul 10, 2010)

How do you know the horn controller (whistle controller) in your transformer is working? It it is not working, the horn relay will not pull in to operate the horn. Is there a wire from the pickup roller to the horn relay?


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## T-Man (May 16, 2008)

Always check the ground. The connections may need cleaning. Then a bad soldered joint could exist.


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## rgodin (Jan 11, 2013)

Thanks, will check the wire from the pickup to the relay. The whistle controller works on the transformer, I have tested it with several whistlers and it operated fine.
Thanks again, will let you know what I find.
Ron


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## BigAl56 (Dec 14, 2011)

You have a fresh battery in there? The horn circuit is very simple. A bicycle horn powered by a D battery controlled by a DC relay. If you can trip the relay by hand and the horn blows fine than the problem is the relay circuit.


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## rgodin (Jan 11, 2013)

Thanks for the reply. I will check, and likely redo the whole relay.
Thanks again,
Ron


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## servoguy (Jul 10, 2010)

Before you take anything apart, check continuity from the pickup roller to one of the terminals on the relay. I assume you have a meter. If you don't, go to Harbor Freight and buy one for $5. Check the continuity of the relay coil. Put the loco on the track and turn the transformer up to 10 volts with the E unit in neutral. See if there is any AC voltage on any of the relay terminals. You should remove the battery for these tests.


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## rgodin (Jan 11, 2013)

Thanks for the suggestions. Here is what I found. I do have a meter.
With the power off I checked continuity with all the 4 terminals and reading stayed at 0. With the power on and at about 10 volts with the engine in neutral I got readings from all 4 terminal in the 9.5 volt range. This was done with the battery out. Can you please interpret these results? I am not sure what they mean.
Thanks again for you help with this.
Ron


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## servoguy (Jul 10, 2010)

Give me a few days to check a couple of Alco diesels I have with horns. 

BTW, you don't check continuity with the meter on AC or DC volts. You check it with the meter on a low ohms scale. Then the meter will read a small number if you have continuity and open circuit if you don't have continuity. 

Can you tell which terminal goes to the relay coil and check continuity from that terminal to the frame of the loco?


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## gunrunnerjohn (Nov 10, 2010)

Don't check continuity with ANY power on ANYTHING! When you're measuring resistance with the meter, it's strictly power off, and no batteries either!


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## TrainLarry (Jan 15, 2012)

Ron,
If the relay activates when the transformer is on and the whistle button is pushed, then the relay is good. Make sure the battery contacts and the relay contacts are very clean and free of dirt and corrosion. Install a fresh battery and close the relay contacts by hand. The horn should blow. If it does not, check the wire from the horn to the relay to make sure it is soldered to the proper contact. You may need to also unscrew the horn from its' mounting bracket and clean the metal-to-metal contact to insure good electrical ground contact. Clean the battery ground contact also. Remember, we're talking only battery voltage that goes through the frame to complete the circuit for the horn. A little resistance in the ground circuit of the battery can cause the horn to not operate properly, even if the relay works properly.
Your observation about the engine speeding up and the lights getting brighter is normal. The transformer boosts the AC voltage a bit to help the whistle motors blow in the tenders of steam locomotives. 

Larry


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## rgodin (Jan 11, 2013)

OK, no power from anywhere. Continuity from pickup roller registered small numbers on all 5 terminals of the relay. 
The two terminals connected to the coil (one each from top and bottom of coil wires) show infinity with the frame of the loco. 
I also checked what the whistle button does while loco is under power, with and without the battery, same results with both, pressing the whistle button increased loco speed and lamp brightness.
I also followed the wiring diagram and all wires connected to the relay appear to be correct. Also, with power on, pushing the whistle button closes the contact on the relay with or without the battery but no horn. 
More tests: with the battery in and no other power closing the contacts on the relay sounds the horn, also touching the relay frame with the terminal connected to the horn sounds the horn.


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## rgodin (Jan 11, 2013)

I think i have found the problem, I hope. Pushing the whistle button closes the contact on the relay but with very little pressure, not enough to sound the horn. When I push the whistle button and add a little pressure to the lower contact, presto, the horn sounds. 
Now to figure a solution. 
Thanks for all your help, it is much appreciated. You all keep beginners like me from giving up in frustration from lack of printed problem solving info.
Cheers,
Ron


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## rgodin (Jan 11, 2013)

That did it!!!!!!!!!
Just a little bend on the lower copper contact strip and now the contact is close (but not too close) and now when I push the horn button the contacts come together with enough pressure and I've got horn!!!
Thanks again,
Ron


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## TrainLarry (Jan 15, 2012)

Make sure the relay contacts are very clean. Polish both contacts with very fine emery cloth, and clean any residue off with alcohol or naphtha. Make sure the movable contact is touching the fixed contact square, and not at an angle. Very lightly bend the contacts if necessary to insure they meet squarely. Also make sure the movable contact is free to move at its' hinge points at the back, and not hanging up by dirt or corrosion.

Larry


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## servoguy (Jul 10, 2010)

Checking continuity with power shouldn't hurt the meter, but it will certainly give you strange readings.


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## gunrunnerjohn (Nov 10, 2010)

Rather than emery cloth, you can use a trick that I've used since the 60's. Take a thin cardboard strip, hold the contacts together, and pull the strip through them. It does a great job cleaning, but doesn't take off contact material.


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## rgodin (Jan 11, 2013)

Thanks John,
Great trick.
Thanks again for your help and all the other folks at MTF with suggestions and ideas on solving this problem!
Ron


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## gunrunnerjohn (Nov 10, 2010)

I was taught that trick at IBM when I worked there, my first job out of the service. Back then, there were a LOT of electromechanical data processing machines, and relays and other contacts figured prominently in the proper operation. You had to know how to clean the contacts without screwing them up.


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## servoguy (Jul 10, 2010)

I have used the striker strip from book matches to clean contacts on mechanical thermostats. 

You can also use crocus cloth which is very fine. I don't think you can find emery cloth fine enough.


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## rgodin (Jan 11, 2013)

*Great tip thanks!*

That's a great tip for cleaning contacts, I was worried even using 600 paper that I might be wearing them thin. They sure hired some smart people back in the day at Itty Bitty Machiines!
I cut a corner from a manila folder and added some cleaner, the cleaner soaks through both sides and it cleans both top and bottom contacts great.
Thanks again,
Cheers,
Ron


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## gunrunnerjohn (Nov 10, 2010)

I try to use the least abrasive method to clean contacts, most of the time the paper works. If not, I have a contact burnishing tool (a leftover from my 60's IBM days) that also does a great job.


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