Lucas 9H horn not working. Repairable?

[abri]

I've got a horn that makes no sound when you connect it to power and earth on its terminals.

1st question: Does the body also have to earth on the car via its bracket for it to work?

2nd question: If no sound comes from it, is there anything a non-professional with a modest tool kit can do to repair it? I see there are two possible adjustments, a large one in the middle that can be turned with a flat screwdriver after loosening the lock nut - and a small screw off to the side.

Any advice will be appreciated.

[captain]

Hi horn diaphragm probably seized. normally a good knock with a hide hammer will cure whilst holding the power on, and as long as there is pos + and neg _ it does not have to be earthed to the body

[abri]

Thanks captain....I will try that.

[dklawson]

If tapping the horn does not help, you have nothing to loose by trying to work on the horn yourself.

Mark the top and bottom housings so you know how they line up. Likewise, make center punch marks between the big nut, its screw, and the horn body. Likewise, make center punch marks between the little Phillips head screws and the horn body.

Drill out the rivets that are used to stake the two halves of the body together. Carefully separate the parts and clean all the rust from the horn contacts you will find inside. Once you have all the rust removed, put the pieces back together and replace the staked points with #8 machine screws. After that, apply power to the terminals and make adjustments to the big nut and its screw.

I believe there are also some YouTube videos on how to restore and adjust old Lucas horns.

[abri]

Thanks a lot for the help. The horn bellowed back to life after a sharp tap with a heavy screwdriver handle. A bit hoarse at first but after some playing with the screws she sings the opera once more

[captain]

Thanks a lot for the help. The horn bellowed back to life after a sharp tap with a heavy screwdriver handle. A bit hoarse at first but after some playing with the screws she sings the opera once more

Good Man, my old mechanic tutor used to say " if in doubt hit it a clout" FOR THOSE OF YOU LADS OVER THE BORDER A CLOUT IS SCOTCH FOR SMACK