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TR2/3/3A Where's the horn ground?

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Jim_Stevens

Jim_Stevens

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Morning, Men:
Can someone tell me where the ground for the horn goes after it comes out of the trafficator? I have an intermittent horn, with both hi and low tested sat. Horn will work strong and fine one minute, but not at all the next. The 12-V bullets I shined up, but the wire for the ground side comes out of the trafficator tube and "disappears" into the engine compartment. I've already shined up all the grounds that are on the body just aft and outboard of the two horns. Full disclosure- I have the Bastuck slip ring unit for my R&P steering...

Does the the trafficactor itself ground it out when the button is pushed?

I hate to run around w a bad horn, since I have had to use them in earnest..... Jim
 
Are you referring to the brown/black wire? On mine all wires from the steering box run as a wrapped bundle to that confusion of wires at the top front of the left wing:

ControlHeadWiring.jpg


The brown/black wire emerging there goes into a female double bullet connector to join it to a pair of other (possibly larger) brown/black wires - one for each horn.

But since you have added a slip ring then your arrangement may be different or even unique to your car - but I would think the principle is the same: a ground controlled by the horn button that provides a ground to the always-powered horns.
 
Off topic, sorry:

Geo, what are the two downward facing round thingies in front of the lower radiator shield?
 
doc50 said:
...what are the two downward facing round thingies in front of the lower radiator shield?
Click to expand...

Those are two pieces of bar stock I use to mount an air dam. I had a pair of crutch tips over then as I worked to minimized the damage when I bang my head into one.

Here's the air dam in place:

TR3-Dam2_zps3d61c84d.jpg


And a look at a bracket:

TR3-Dam3_zps784f2618.jpg


The idea is to throw air at the lower third of the radiator as it is more or less out of the usual sir flow.
 
Just a thought, Jim, a lot of my horn problems proved to be a bullet sleeve that was broken inside the vinyl sleeve. Just like yours, it would work sometimes (almost always when testing in the driveway) and other times not (always when I was trying to warn someone I was in the spot they were moving into).

I even added a relay, thinking the old contacts in the trafficator head were the problem.
 
I had a similar problem a few years back. Tried everything including sounding the horn for a prolonged period to clean the contacts while out in the country. Had a lot of cows looking my way as I went down some back road. Finally solved my problem by tuning the horns IAW this Lucas Manual: https://www.vintagemg.com/articlepdfs/thorns1-2.pdf . If all else fails try this. I have never had a problem with my horns since the adjustments were made. Good luck.

Frank D.........
TS42756L
 
Interesting article, but it seems there are some typos (or OCR errors). I'm pretty sure that should be 8 amps for a WT618 horn rather than 3.

untitled_2.jpg~original


untitled2.jpg~original
 
I love watching some threads grow and grow...and the OP seems to have forgotten all about it.
 
Not at all! Those pesky day jobs. I tuned the horns already, and as I said shined up all the contacts. Still intermittent. I think fundamentally, the question is Does the horn button itself make the ground, or does it just switch and the ground wire come down the tube? Jim
 
The wiring diagram shows the ground connection is right at the horn button. Some part of the steering shaft needs to be grounded. Le
 
The button grounds the wire that runs down the tube, to make the horns sound. The other side of the button is grounded to the steering wheel. I don't know for sure, but my guess is that the current flows through the upper part of the shaft, then the 'lantern' springs and to ground through the lower part of the stator tube, it's compression fitting, and the steering box housing. Hopefully they don't rely on the steering box to ground the shaft through the bearings and/or peg.
 
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