horn assembly. am i missing something?

[roadstermike]

My 67.5 horn assembly is either not hooked up correcty or I'm missing something. See the photos. With the steering wheel off, I can wire the small push in tab (lower left) and the center ring on the turn signal assembly and can get the horn to work. I hook it up and nothing. I just bought the o-ring from dean and still no luck. The on line layout is not helping. Any insight? I sure the PO did something like the rest of the wiring. Thanks.

[Solex68]

I was working on my steering wheel today. Learned a lot.
Anyway I have photos of my stock wheel removal and my Grant Steering wheel install. I have a 68 311 so my column may be different but here are my photos:

1st photo is the original wheel being removed
2nd photo shows the column exposed. There is a thin copper band that pushes outward to make contact with the wheel (for the horn)
3rd the grant adapter installed
4th the horn cable connection from the adapter to the horn button
The last photo is where I left off the silver ring. That was a mistake. I need to install it because that is what my horn button plugs into.

[Nissanman]

@roadstermike,
that little plunger rubs on the brass ring on the underside of the steering wheel hub.
Then there is a little wire pigtail that screws into the top side of the steering wheel hub and connects to the chromed horn ring.
This is the connection to the "live" horn ring that is grounded when the horn button is depressed.
The other end of the pigtail goes under the machine screw on the chrome horn button as shown in the pic.

Fairlady (Large).jpg

Without the little pigtail, the horn circuit will be inoperative.

And you are right, most of the Factory manuals don't show all the parts and what they show is not in the correct order of assembly

[roadstermike]

Okay, my steering wheel does not have a brass ring for the plunger tab to rub against and don't have a pigtail wire to connect to the rest of the assembly. Maybe its time to get a different steering wheel rather than fix this one. Thanks

[peter]

it looks on like that on the backside of the steering wheel is something missing, there has to be a sliding ring that's isolated, but at that place I see some drilled holes.

[Nissanman]

You could probably make your own contact ring from an annulus of brass sheet bonded to the wheel hub.
That's all the original is.
All you need then is a wire soldered to it to exit the hole on the top side of the hub with an eye connector on the end

[roadstermike]

Im reviving this one as I still don't have my horn working. Does anyone have a few photos of how their early horn assembly is assembled? with the horn button off and maybe how the two pieces of the horn button are put together would be helpful too. Are there isolator tabs between these pieces? I must be missing something or I have mine assembled wrong. When I plug in the power source and horn assembled, the horn just blows without pushing on the button.

I can post more photos tomorrow if that will help. thanks.

[Nissanman]

I'll take some pics. tomorrow for you.
For something so flamin' simple, Datsun made this quite complicated

I think all you are missing is some isolating fibre washers since, obviously, the horn wire is grounding out somewhere.

[Skyman]

I'll take some pics. tomorrow for you.
For something so flamin' simple, Datsun made this quite complicated

I think all you are missing is some isolating fibre washers since, obviously, the horn wire is grounding out somewhere.

You may be correct. these can be made out of a piece of foam if the original washer is to badly gone, or missing all together.

[jamesw]

Everything on my horn circuit is operative but the button is not making ground or it's always making ground. This is on a 67.5 like yours Kyle.

Can you pop the Datsun button off and then shoot some pictures of what is supposed to be underneath? I have my little wire connected and then there is a big plastic ring and a metal ring but nothing making a "spring" that you can push to make contact.

Thanks
James

[Gregs672000]

I haven't had a horn in nearly 30yrs. It was one of those "Hey, let's take this apart..." BOING! "Hmm, anybody see where that landed?" Nope.

[Nissanman]

OK boys and girls, at great expense to the management, I have taken the device apart and photographed all the pits and bieces.
First up, let me say that the designer could have made it more complicated but he must have run out of time


In the beginning there was a wheel.
The horn button has a small notch at the junction of the button and the body right at the base of the button.
Insert a small flat bladed screwdriver into the notch and lever gently to remove the button.


The underside of the button shows the wave spring that holds the "d" emblem in place as well as holding the decorative button to the body.


The steering wheel now shows the horn HOT wire and the screw terminal to which it attaches.
The HOT plate is LIVE with 12V from the Horn Relay.


With the steering wheel removed, you can see the contact button at 2 o'clock.
This is the 12V feed and the button rubs on the contact ring bonded to the backside of the steering wheel hub......


......which is shown here.


The HOT wire appears as a screw terminal on the steering wheel hub and is insulated from the metal parts.
The little pig tail goes through the button body......


......and is screwed down on this plate at 1 o'clock.


The backside of the horn body shows the two locating tabs at 3 and 9 o'clock which lock into the steering wheel hub.


This what the parts book describes as the Horn Spring. It is a round piece of rubber section designed to separate the GROUND and HOT parts of the horn metal work.


The horn spring in the correct position.


Now here is where all the complication arises.
These are the component parts of the horn button.
From the left we have the chrome horn button, insulating disc, grounding ring and HOT ring.


The insulating disc is inserted into the horn ring......


......the grounding ring is located over the insulating disc where the little bosses are.......


......the HOT ring is placed over the insulating ring bosses and held down with three metal thread screws with insulating washers.
That means that once the 12V pig tail is screwed to the HOT plate, the horn relay can be energised by forcing the HOT plate onto the grounded plate.
The contact to ground out the relay wire is done between the grounding plate which is grounded when the steering wheel retaining nut in tightened, and the HOT plate under the spring tension of the rubber ring.


Now, that wasn't so hard, was it

Here is the line drawing from the Parts Manual: -

SP310 steering wheel.jpg

It seems to avoid all the important parts that make up the actual horn contacts.
Ah well! Such is Life!

[roadstermike]

Nissanman, great detail. Thank you. Well it looks like im missing th insulating disc and hot ring. No wonder I could not figure it out. This is what I have for my 67.5 wheel. Anyone out there have a spare insulationg disc and hot ring?

[Skyman]

Great write up Nissanman. I was going to take pictures for James today, and you beat me to it.

Roadstermike, the rubber ring on the right should be the insulating disk. I may have some horn pieces from a parts car if you are not able to find anything.

[jamesw]

Nissanman: Thanks!!!!

Kyle,

I would still appreciate them as the 67.5 horn button is slightly different.

Cheers
James