CMP Ford F60S

[Jacques Reed]

Hi Richard,

There is not much info on the horn that I have found. Nothing in the Maintenance Manual. Your internals looks similar to my original Cab 13 horn. There is a condenser fitted to prevent arcing at the make and break contact similar to the condenser used at the points.

The only adjustments you can make is to move the two nuts so that the contacts open and close rapidly to vibrate the diaphragm. The outer one is just a jam nut to prevent the inner nut from moving.
From memory I think you can also adjust the position of the laminated bar relative to the coil. It must not touch coil but not so far away as to not be pulled by the coil.

Basically if there is no sound, the diaphragm is not vibrating so move the inner nut until it does then lock it with the outer one. It is Science 101 basically- How a doorbell works, but a diaphragm substituted for a striker.
If no sound after doing that then perhaps the coil is burnt out or the laminate bar needs to be moved. Polarity should not matter.
Hope this helps.