No Hooter.

[A10 JWO]

Started sorting out the ancillaries on my rebuild. Found the hooter in a box of bits and put it straight across a charged 12 volt battery, not a squeak ! Is it time to throw it away, bog standard 1971 A65. 

[AWJDThumper]

Most horns have an adjustment screw on the back. Try screwing it either way to see whether the horn starts vibrating.

[A10 JWO]

Thanks, this is a Lucas horn with the nut on the back, will try it out tomorrow.

[AWJDThumper]

I'll check the Lucas horn I've got lying around and work out which way the adjustment works. In principle, if you screw it fully in the right direction you should be able to measure the resistance of the solenoid coil on a multimeter.

[AWJDThumper]

If you turn the screw clockwise, it will close the points gap and at some point you should be able to measure the resistance of the solenoid coil (< 0.1 Ohm). Turning the screw the other way should give an open circuit at some point. The normal way of adjusting it is to turn the screw anti-clockwise until the points just open and then screw it back in about 1/4 turn.

NB: Do not adjust the big screw in the middle of the back of the horn!!

If the above does not give you a working horn then you can always drill out the rivets and take it apart to check it in more detail.

[A10 JWO]

Thanks Thumper.

[A10 JWO]

The screw sheared off,  Anyone get a spare correct one for a A65 OIF, think it is Lucas ? Thanks.

[AWJDThumper]

If you send it to me, I'll happily have a go at fixing and servicing it for you. Presuming its a Lucas horn as shown below? just PM me if you want me to look at it.

[A10 JWO]

PM Sent thank you. Colin 

[AWJDThumper]

Horn is now working again but needed an internal service. For anyone with a similar problem, please note that the adjustment screw on the back of the horn has a left-hand thread and can be easily sheared by inadvertently trying to undo it by turning it the wrong way.

[A10 JWO]

My horn has been repaired by a member who is refusing payment which just shows how us bikers stick together. I will donate the money I wanted to give him to the Poppy Appeal at the Royal British Legion. A big thank you to this member. I did not want to fit a £10 ebay horn so this means a lot to my restoration.

[A10 JWO]

I have my serviced and resprayed hooter back from this members workshop, very grateful.