Talk Morgan Forums Morgan Sports Cars Classic Morgans (pre-CX) 3.7 Roadster

Eek! What a mess - hopefully mine aren't like that. Time will tell!

The mmc horns a shite and fail. Easy to replace as Richard says

Ones on our BMW Mini are no better despite being mounted out of the crud - had to replace a failed low note one last year. Horns built to a price seem to be consumables nowadays. I wouldn't dream of taking a failed one apart, just buy another pair on eBay for a few quid and keep one as a spare.

The huge 6 volt Marelli one on my 1945 Guzzi is a work of art by comparison, so was happy to spend time rebuilding and tuning that.

Replaced mine with twin Fiamm.

Cant think of the last time I used a horn on any car, other than the MOT test, perhaps had I any Italian chromosomes in my makeup then I might think to drive without an operational horn an insult to my machismo..?

Richard, have to admit in times past, I too stripped and repaired old horns but since the sealed for life and throw away society took over things, my horns would oft times only be checked for operation in pre MOT checks, and if found to be inoperative, a sharp rap with a spanner while someone is operated the horn push tends to do the trick in shocking the internal connections back into action, that have fouled up to my previously referred to lack of use... (-:

Typing this caused me to remember Colin, aka Spanner Juggler and the sound of his very effective claxon fitted to his +8 when I met up with him and other MSCC DG and eMog cyber friends for the first time at the MSCC Lakes weekend.... Happy days.. (-:

Yes that claxon was special

The horns, high and low are interlinked and have two electrical connections. Disconnect the wiring and using your meter check to see what's happening and are you sure both are working. If it sounds a bit weak then only one is functioning, if it blows your socks off then both are chirping. check those 4 electrical connectors and as Richard said the fuse. vibration from a running engine might be aiding a dodgy connection and the fuses and relays are notorious for slight corrosion. Whatever it is its going to be simple. As far as I remember there's now relay in the circuit.

Thanks Sewin - I have cleaned the copper contact on the steering wheel hub,changed the fuse, cleaned all the horn connectors (4) and the horns now work just fine. They still struggle when the engine isn't running, but as I am unlikely to use the horn without the engine running I am not going to investigate any further. It may be a poor earth but that will mean accessing the light switch in the steering column, which I will do if I have further problems.

Looking at the relays (and diagram in the box) there doesn't seem to be a horn relay.

My bet is still on corrosion on the surface of the internal diaphragm, perhaps a winter job ?

Correct, there are no relays in horn circuit Les even on models with twin high/low ones such as Roadsters. In any case this is the industry norm. After market air horns requiring a compressor drawing considerably more current, especially inrush, are a different matter however. If the situation re-occurs suggest buying a cheap twin tone pair on eBay, they will be no worse than OE. Even my Yorkshire roots wouldn't justify my taking modern ones apart.