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| | | Forums66 Topics128,089 Posts1,056,005 Members48,430 | | Most Online14,466 Apr 26th, 2026 | | AD Chevy Trucks Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Oct 2016 Posts: 496 Shop Shark | | Shop Shark Joined: Oct 2016 Posts: 496 | My father in law just gave me a working OLD aaaooooogah horn that works but I'm sure its 6v. Has anyone used one of these on a 12v system? I'd hate to tear it up since it's a family deal.
1950 SUBURBAN / SCHOOL BUS A.K.A "THE SCHOOL RUST"
| | | | | Joined: Aug 2005 Posts: 6,377 Ex Hall Monitor | | Ex Hall Monitor Joined: Aug 2005 Posts: 6,377 | A regular vibrator horn will work OK for short periods of use. I've never tried a 6v klaxon on 12v. If it were me I wouldn't do it. It might be OK but you might fry it too. Maybe someone who's actually done it will chime in.
Save a life, adopt a senior shelter pet. The three main causes of blindness: Cataracts, Politics, Religion. Name your dog Naked so you can walk Naked in the park.
| | | | | Joined: Oct 2016 Posts: 496 Shop Shark | | Shop Shark Joined: Oct 2016 Posts: 496 | I just scraped some grime off the label. I think it's a klaxon. No flair on the horn.
1950 SUBURBAN / SCHOOL BUS A.K.A "THE SCHOOL RUST"
| | | | | Joined: Apr 2005 Posts: 7,440 Bolter | | Bolter Joined: Apr 2005 Posts: 7,440 | I have done it but only very short bursts.ðŸ›
Martin '62 Chevy C-10 Stepside Shortbed (Restomod in progress) '47 Chevy 3100 5 Window (long term project) ‘65 Chevy Biscayne (Emily) ‘39 Dodge Business Coupe (Clarence) “I fought the law and the law won" now I are a retired one! Support those brave men/women who stand the "Thin Blue Line"! Hug a cop! USAF 1965-1969 Weather Observation Tech (I got paid to look at the clouds)
| | | | | Joined: Oct 2016 Posts: 496 Shop Shark | | Shop Shark Joined: Oct 2016 Posts: 496 | Is there a "reducer" I can use to reduce the voltage to 6v? I've heard of some used on heaters before.
1950 SUBURBAN / SCHOOL BUS A.K.A "THE SCHOOL RUST"
| | | | | Joined: Jun 2017 Posts: 370 Shop Shark | | Shop Shark Joined: Jun 2017 Posts: 370 | I have one and had to do a little repair on it. The wiring is very fragile and the motor requires oiling periodically. After seeing the guts, I wouldn’t put 12 thru it. It would be cheap and easy to wire in a transformer.https://www.ebay.com/itm/12-Volt-to-6-Volt-Voltage-Reducer-Heater-Blower-Motor-Voltage-Reducer-6V-wiper/171695758294?hash=item27f9dd5bd6:g:WV4AAOSwQJhUjOWk
Don
Can’t begin to tell you how much I hate the name Stovebolt.
| | | | | Joined: Oct 2016 Posts: 496 Shop Shark | | Shop Shark Joined: Oct 2016 Posts: 496 | Just ordered the reducer.....thanks Don.
1950 SUBURBAN / SCHOOL BUS A.K.A "THE SCHOOL RUST"
| | | | | Joined: Jun 2006 Posts: 693 'Bolter | | 'Bolter Joined: Jun 2006 Posts: 693 | that reducer is just a 4-ohm resistor. to drop the voltage from 12v to 6v the load must draw 1.5A. I have no idea what your horn will draw, but if it isn't in that area the 'reducer' will drop a different voltage and your horn may not work. By the way, in operation with 1.5A, the resistor will dissipate 9 watts and will get quite warm - consider mounting it to a heat sink, like the firewall or inner fender. | | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | I got a large resistor years ago that had exposed wire windings on one side do you could adjust the resistance. Get one, put the tab in the middle of the windings and have a friend measure the voltage when the horn is on, slide the dab to adjust the voltage.
Ed
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires. '47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle. '54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed. '55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
| | | | | Joined: Oct 2016 Posts: 496 Shop Shark | | Shop Shark Joined: Oct 2016 Posts: 496 | Do I place the resistor before (battery side) or after the relay (horn side)?
1950 SUBURBAN / SCHOOL BUS A.K.A "THE SCHOOL RUST"
| | | | | Joined: May 2015 Posts: 11,054 Housekeeping (Moderator) Making a Stovebolt Bed & Paint and Body Shop Forums | | Housekeeping (Moderator) Making a Stovebolt Bed & Paint and Body Shop Forums Joined: May 2015 Posts: 11,054 | As long as the resistor is in the switched circuit and not the control circuit of the relay, it doesn't matter. Reminds me of when I had starter problems that turned out to be a high resistance connection of the engine ground cable. Swapped out two starters I thought were bad until I found that paint around the bolt where the shop connected the ground cable. Voltage drop is voltage drop, not matter where it occurs.
Kevin 1951 Chevy 3100 work truckFollow this saga in Project JournalPhotos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together. | | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | After the relay, just before the horn, electrically.
Ed
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires. '47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle. '54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed. '55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
| | | | | Joined: Oct 2016 Posts: 496 Shop Shark | | Shop Shark Joined: Oct 2016 Posts: 496 |
1950 SUBURBAN / SCHOOL BUS A.K.A "THE SCHOOL RUST"
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