Air horns.

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trooper
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Air horns.

Post by trooper »

WoW! :? Do I have a problem? I've always fitted a set of air horns that I've swapped from car to car over the years, except, to my present motor, simply because the horn is very difficult to access. Anyway I arranged for my local garage to do the job & decided to make sure they were okay first, not having had them working for app 2years. Did the necessary with temp wiring etc & they didn't work? So now I'm investigating. I removed the trumpet air linkage to the compressor & made a temporary connection from it to the car battery. The comp ran but didn't sound as I'd expected it to. Hmmm! Now on the comp, the connections are clearly marked + pos & - neg which is naturally, how I've always wired them up using a relay & never had a problem. So I connected the wires again & put my finger over the comp outlet to the trumpets, it was "sucking" instead of blowing!!! As they've always worked when I've had them on my previous cars I was stunned. So because of the comp sucking, I reversed the polarity & it ran as it should.
Over to you for possible reasons. Don't forget, I'm linking the comp direct to the car battery to test it.
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Someone-Else
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Air horns.

Post by Someone-Else »

so whats your question?
It runs run way not the other, swap the supply round
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ayjay
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Air horns.

Post by ayjay »

trooper wrote: Sat Nov 07, 2020 3:50 pm I've always fitted a set of air horns that I've swapped from car to car over the years, .....
Did the horns by any chance begin life on a car with a positive earth system?
One day it will all be firewood.
trooper
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Air horns.

Post by trooper »

Good question ayjay & thanks for your input. These were bought new & there's no mention on the fitting instructions of a pozzy earth.
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Someone-Else
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Air horns.

Post by Someone-Else »

I would say you are overlooking the obvious.

The direction a D.C. motor runs depends on the polarity. So if you swap the polarity round the motor will run in the opposite direction.
It looks like someone has connected it the wrong way round, so as I said earlier, if you find the compressor is sucking instead of blowing, it really is a simple case of swap the polarity round, because the motor is running in the wrong direction.
Above are my opinions Below is my signature.

Would you hit a nail with a shoe because you don't have a hammer? of course not, then why work on anything electrical without a means of testing Click Here to buy a "tester" just because it works, does NOT mean it is safe.

:mrgreen: If gloom had a voice, it would be me.

:idea1: Click Here for a video how to add/change pictures


Inept people use the QUOTE BUTTON instead of the QUICK REPLY section :-)
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