Horn Relay

[Linda]

The Tech Wiki states horn relays from various models work:
“Horn relay that fits ,'70-'73 Datsun 240Z's '& '65-'74 Datsun 520,521 '& 620 model pickups fits ALL '65-'70 Datsun Roadsters”
Any relays that you have found that are good?
Linda

[itsa68]

In a pinch you could use a 510 relay 26320-89905.
I think that is the same as the Duralast Relay 19348.

Long time ago I had used the Datsun 620 relay and it was not a problem.

Cheers
Ray B.

[Daryl Smith]

Couldn't any of the standard 4/5 pole relays work? I mean it is just a 12V relay isn't it?
What is so 'special' about a horn relay?

[Linda]

Duralast part says 15 A . Is that OK? Lists it for the 510.
https://www.autozone.com/electrical-and ... 953396_0_0

Linda

[redroadster]

The horn puts out high voltage
It has beefy contacts to last long

The HORN is a cimbal like steel plate on spring steel and vibrates off another flexible thin plate many times a second ,when an electro magnet COIL + CAPACITOR ( sound familiar ) when connected to 12 v it loads up 2-4k volts in the coil and cap. then if you touch or are around the St wheel contacts it will deliver it to you , and sitting behind the wheel can give you a long shock ... So can a A/C clutch ,more prevelent in hot humid days
If you're trouble shooting a inop horn system the manuf. Demands you first insert a test lite to replace the horns ....because older techs have had shock that caused serious heart problems ....legal problems $$$$$$$$

[Curtis]

https://www.autozone.com/electrical-and ... datsun/510

[Linda]

And from RockAuto, same part:
https://www.rockauto.com/en/catalog/nis ... relay,3468

Linda

[Daryl Smith]

"The horn puts out high voltage
It has beefy contacts to last long"

The horn is 12V like everything else in the car. It may draw a slightly higher amperage(?), but, I would be surprised if a standard 15 or 20 amp relay would not suffice. Contacts are plenty sturdy enough. If you're worried about it, spend a couple extra dollars and put a 40A relay in. Probably $5 or less.

If you're doing a proper restoration, then get the proper relay....

[Linda]

My lucky day, I apparently had bought a previous version of the Duralast,#19347, with lifetime warranty, so Autozone will order the 19348 part for me to replace it for free.... It looks the same except for 2 mounting holes instead of 1 on the old part.
So yes, the 510 relays work, maybe should add to the Tech Wiki

Linda

[DAC21]

I suspect the new two hole relay will look a bit odd with one hole not being populated. Looking at the part there is enough real estate for a third hole dead center. Then you could take off the two original holes with a dremel cutting wheel / band saw making it look like an original one hole part. I don't fancy drilling any new holes to add a second bolt. Alternatively you could cut the head off a second matching bolt and jb weld it to the bracket for a "faux" two bolt look. Probably a bit extreme but doable.

[Linda]

I thought about that. I will drill a center hole for now to mount it, and see how it looks, should be fine for now. The other modifications would make it look more stock, true, but as is, not bad.

Linda

[Curtis]

Or, you could drill a center hole and cut away the other two holes if you really want to go to all that work. If you have a single hole case you can probably exchange the case.

[Linda]

I couldn’t keep the old part, or I might have done that. It was a little beat up though, so this one will be nice and shiny when it arrives.
Linda

[Solex68]

I would decapitate a bolt head and JB weld it over one hole and screw in the relay with the one hole. That way it looks less Pep-Boys. Make sure to swivel the relay to cover the empty hole.

[JT68]

Sure is a lot of discussion about such a simple part. JB weld? Most vendors have correct roadster relays. If you don’t care about originality, almost any standard automotive relay will work if you understand how to wire it. 15amps is plenty.