The Ford Barn

1crosscut · 07-02-2015, 09:41 PM

The original Sparton horn on my 29 AA has always been a really nice sounding horn with a crisp, fast ahooga. A couple of weeks ago I was doing some routine maintenance on the truck and as a part of that I put a couple drops of light oil on the front felt and the shaft at the rear. This last week the horn started to progressively get slower and started to sound more and more like a sick cow. I cleaned and polished the commutator as in the past with fine sand paper but that didn't help. Checked ground, connections, played with the adjustment etc... with no luck.
Any how to make a long story short what I found was that the oiled felt was the problem. I used a can of brake cleaner with the long thin straw attached to the nozzle to reach in and wet the felt. After that I used a small flat bladed screw driver and pressed a rag to the felt sopping out the liquefied oil. I also saturated a bit of the rag and worked it around the shaft to the rear of the commutator and cleaned the commutator too. Didn't take much time and effort to get it all cleaned out and now the horn sounds like a champ again.
Perhaps a good share of the horns that don't sound particularly good might just be over oiled?? It seems logical when a horn isn't sounding right to grab the oil can and give it a few drops. I'd be interested to see if others with sickly sounding horns benefit from cleaning out the old oil and starting fresh like this.

Tom Wesenberg · 07-03-2015, 05:28 AM

The original horn brushes look like a compressed brass screen. I saw a commutator worn out by dirt and oil embedded in the brushes, which then acted like grinding compound.

Rowdy · 07-03-2015, 09:21 AM

The commutator in my Dad's horn is like that. It works for now, but I will eventually need to find a different armerature for it or find some one that can replace the commutator. Rod

Henry1953 · 07-03-2015, 02:59 PM

My horn is sick sounding and doesn't get any better no matter how I adjust it. I am going to try your suggestion. Thanks for the tip.

1crosscut · 07-03-2015, 05:48 PM

Quote:

Originally Posted by Henry1953

My horn is sick sounding and doesn't get any better no matter how I adjust it. I am going to try your suggestion. Thanks for the tip.

I hope it works. Let us know how it goes.

ericr · 07-03-2015, 08:20 PM

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in reply to your situation, yes, I have had over-oiled felts somehow spread oil onto the commutator and detract from horn operation.

07-02-2015, 09:41 PM	#1
1crosscut Senior Member Join Date: Feb 2011 Location: Lincoln, Nebraska Posts: 1,908	Horn fix that might help others. The original Sparton horn on my 29 AA has always been a really nice sounding horn with a crisp, fast ahooga. A couple of weeks ago I was doing some routine maintenance on the truck and as a part of that I put a couple drops of light oil on the front felt and the shaft at the rear. This last week the horn started to progressively get slower and started to sound more and more like a sick cow. I cleaned and polished the commutator as in the past with fine sand paper but that didn't help. Checked ground, connections, played with the adjustment etc... with no luck. Any how to make a long story short what I found was that the oiled felt was the problem. I used a can of brake cleaner with the long thin straw attached to the nozzle to reach in and wet the felt. After that I used a small flat bladed screw driver and pressed a rag to the felt sopping out the liquefied oil. I also saturated a bit of the rag and worked it around the shaft to the rear of the commutator and cleaned the commutator too. Didn't take much time and effort to get it all cleaned out and now the horn sounds like a champ again. Perhaps a good share of the horns that don't sound particularly good might just be over oiled?? It seems logical when a horn isn't sounding right to grab the oil can and give it a few drops. I'd be interested to see if others with sickly sounding horns benefit from cleaning out the old oil and starting fresh like this. __________________ Dave / Lincoln Nebraska

07-03-2015, 05:28 AM	#2
Tom Wesenberg Senior Member Join Date: May 2010 Location: Mpls, MN Posts: 27,582	Re: Horn fix that might help others. The original horn brushes look like a compressed brass screen. I saw a commutator worn out by dirt and oil embedded in the brushes, which then acted like grinding compound.

07-03-2015, 09:21 AM	#3
Rowdy BANNED Join Date: May 2010 Location: Gothenburg Nebraska Just off I-80 Posts: 4,893	Re: Horn fix that might help others. The commutator in my Dad's horn is like that. It works for now, but I will eventually need to find a different armerature for it or find some one that can replace the commutator. Rod __________________ Do the RIGHT thing - Support the H.A.M.B. Alliance!!!!

07-03-2015, 02:59 PM	#4
Henry1953 Senior Member Join Date: Nov 2014 Location: Laurel, MS Posts: 126	Re: Horn fix that might help others. My horn is sick sounding and doesn't get any better no matter how I adjust it. I am going to try your suggestion. Thanks for the tip.

07-03-2015, 08:20 PM	#6
ericr Senior Member Join Date: Apr 2012 Posts: 1,542	Re: Horn fix that might help others. Sponsored Links (Register now to hide all advertisements) in reply to your situation, yes, I have had over-oiled felts somehow spread oil onto the commutator and detract from horn operation.