17 hours ago, Zup said:

Jeff,

Regarding rebuilding your horns--

When I rebuilt mine the gaskets weren't available. I put them back together without the gaskets and they work and sound as original.

Look up seller nikkibid1972 on ebay. He makes a reproduction restoration kit that includes the die-cut gaskets and correct new nuts, bolts and washers. I have bought a couple of sets. Nice kit.

Rob does not have a listing for these currently. 

If you contact him with your request to purchase a set I think he will eventually put together  another round of them for sale.

Zup

 

Rob totally hooked me up.  I reached out to him just as you suggested and he posted a kit for me.  See link below.  I think I may still buy some Hella Sharptones and paint them since I will have to deal with Austin traffic when I take the car out.  I will restore the original horns and have them for safe keeping.  Looking forward to getting the kit!

https://www.ebay.com/itm/New-Datsun-240Z-260Z-Roadster-Horn-Rebuild-Screw-Gasket-Kit/152768263718?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m2749.l2649

Both of the horns, low and high tone, in my 72 240z sound fine but provided the engine is running at idle. If the engine is shut the sound is very thin and barely noticeable. What could be the cause for this? Worn relay?

My guess is low voltage to the horns. Check the voltage at the horns and the horn circuit in the fuse block. There's probably a poor electrical connection in between those two components.

or the battery voltage is low when the car is off and the alternator brings it up when idleing

I guess this is better answer

On 1/28/2020 at 10:19 AM, Mark Maras said:

My guess is low voltage to the horns. Check the voltage at the horns and the horn circuit in the fuse block. There's probably a poor electrical connection in between those two components.

How do you check this relay to verify its still good?

Use a voltmeter. Black wire to ground and the red wire to the relay connection that goes to the horns. Have a friend push the horn button. The reading should be the voltage going to the horns. Did you measure the voltage at each horn connection? That would tell you if there's a difference in voltage to each horn. If the voltage is the same the problem is in the horn.