VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1929-1932 Horn

Jarhead,

Please go back to my post on how I tested my horn. I'm just a dumb country boy but trust me.

Lets first see if your horn is shorted. After that let me know.

Hi jarhead,

Take a deep breath and then let it out slowly. Now follow John's instructions. If the horn works on the bench the next step is to insure that neither or the two terminals are shorted to the horn. This can be checked either with a voltmeter or lacking that device, connect the HOT WIRE (6Volt+) to one of the two terminals. Now touch the horn body to any metal object on the car. There should be no reaction. Now place the wire on the other terminal and repeat the touching to a metal spot on the car. Again, if no reaction---you are home free.

Now it is just a matter of following the instructions listed above.

I disconnected it. And its in a box. It can wouldn't hurt to have it looked at by someone who know's what they're doing. The terminal nuts, washers and "connection" show years of rust. There appears to be no rubber separator from the rest of the body. It was good and loud last night, for all I know it has never been worked on. Thanks.

i was taught that when checking horns an ampmeter should be used when adjusting,if you move the adjusting screw the electro magnet instead of vibrating just pulls on and gives a dead short,there is a small set of points that are moved by the adjuster and should just be touching,some manufactures use a bi-metal strip which makes and brakes the circuit,as to wiring it is dead simple,you need a feed usually the live wire that the rest of the car electrics use,then you need a switch in the circuit in this case the horn button for the return,so in effect you are earthing the horn through the horn button,most faults are usually traced to this wire that runs up your column and also believe it or not the column itself not having a good earth,if smoke comes out of horn the windings on the electromagnet are dead shorting,adjust the horn with the ampmeter in line so that there is no draw and then slowly turn the adjuster till horn blows/vibrates keep watching the ampmeter should read 2amps if its more check points contact or bimetal strip,stiff diaphram,column and horn button easly checked by bulb and wire,attach one wire to a known good terminal or onto battery live use other wire to earth on horn button and column,should lite up if all good, infact this is a horn circuit simplified,good luck

Zodiac,

You give a very good explaination. I never learned this about adjusting the horn useing the ampmeter but it makes sense to me.

I guess I was lucky my battery charger is in the 2 amp range.

I am NOT an expert like some others, but if the horn is grounded by being connected to the headlight support shouldn't you make sure the headlight support ends really touches metal (is grounded) and not sitting on paint or on a tarpaper pad?

As the JYD said, "The horn does not have to be grounded, but it is grounded to the body when it is bolted to the headlight support."

Good Luck...

gator,

I think that's the point, that the horn electronics ISN'T supposed to be grounded through the case or the headlight support, etc...

that the outer case of the horn may or may not be grounded when bolted to the car is irrelevant to the horn's operation...

as delraymondo says above, it's supposed to work even if you are holding the horn in your hand and it isn't even touching the car...

the internal wiring of the horn is separate from the outer case...


epi

There ya go! Kepi Doodle totally understands about the horn grounding thing.

Gator, again, the horn does not have to be grounded to work! It will work in mid air and not touching anything. However, when it is bolted to the headlight bar the horn (casing) is grounded to the metal like like everything else that is bolted directly to the body or frame, but the horn still does not have to be grounded to work. :eek: :eek:

But the horn circuit has to be grounded for the horn to work! If the horn was in mid air and not touching anything it would not work because the circuit would not be grounded.

The horn itself can be in held in mid air and wired to the mast jacket bushing with one wire and to the light switch (or any "hot" source) with the other wire and it will work. The horn body does not have to be touching anything. The horn can be connected to a battery on the floor and it will work. The horn can be connected to a battery eliminator on the work bench and it will work. The horn body itself does not have to be grounded.

yes, the horn CIRCUIT has to be grounded for the horn to sound...BUT the metal CASE of the horn IS NOT part of the horn circuit...that's why there are TWO wires connected to the horn circuit...


epi

Right on Kepi Doodle!

If the terms "grounded" & "earth" are dropped & we use the terms negative & positive it might save misunderstandings.(Is there such a word?)
The chassis is not an earth but a means of linking all the negatives together, on a neg' return car or the positive on a pos' return car. Fibre glass cars & petro-chemical vehicles tend to have a positive loom as well as a negitive loom & the battery is not linked to the vehicle structure.
So if you hold a working horn in your hand & connect the positive to one horn terminal & to the positive on a battery "+" terminal, then connect the negative to the "-" terminal the horn will sound & you'll upset the neighbours with all these horns going off!!

Yes Kipper!

There is a word called "MISUNDERSTANDING".

Some get so hung-up on making their point they have no "UNDERSTANDING".

Of course I am very understanding!

"Of course I am very understanding!"

So no misunderstanding, we all understand what we're understanding about understanding what we're understanding.

I think!

Huh? :confused: :confused: ha ha!

Is he any relation to Mr. Mack???

Hoppy,

He who? Or Hee Hee!

ok...hope there isn't a test later.