Weak air horn

[Kagor 0]

Hi,

 

I need the horn fixed for the MOT. It is a FIAMM brand air horn, with a compressor feeding the horn by a hose.

The terminals to the compressor look clean. and I can hear the a buzzing sound when activated. Occasionally, a verry weak screachy sound comes out of the horn, but I expect it to be louder and more consistent to call it healthy.
I have disassembled to some extent. Detached the two plastic lids on the top and the bottom of the plastic horn, found nothing more than regular dust, the core looked clean.
 

Then, on the compressor side, I took the top lid off (three bolts), the sight was not a pleasant one, some residue from a sponge like material on the intake side, a dead spider, a small block of porous material and a loosely positioned spring on top of that block (don't  know if this is by design).

Anyone with similar issues and any clue about how a normal horn should look like on the inside?


Best regards,
Kagor  

[Simes 248 2 Cars]

Is this the original black twin horn unit?

I never had much success with those.

 

I’d replace with a twin air horn set. The trumpets down in the same place.

 

 

[Kagor 0]

Hi,

 

it looks like this one here (borrowed image), 


Seems like the trumpet body has two canals, two mirrored parts fused together. Cost effective 
About the hose, there is a "tee pipe" and the hose is connected to only one of the two connections. I guess one is inlet and the other is outlet for the air.

I cleaned out as much as I could, will see if it sounds better now. Otherwise I'll have to replace it with an electric horn I have at hand, not as cool.

But the question still remains  If anyone has restored one of these properly, let me know.
 

 

Best regards,
Kagor

[Simes 248 2 Cars]

You get a large compressor in a twin horn set it’s normally a fiamm too.

You could get one to replace. I think I’ve got one here but it hasn’t been used for 15 or so years!

[Tom Fenton 1,542]

I’ve had both bits fail. Try the horn itself using compressed air to see what you get. The compressor is easy to get another, the horn is not.

[Dimi 7 1 Cars]

Sorry to bring this one again, only in hope someone else can benefit from my results. My air horn is like yours and did not work, I did what you did and cleaned a lot of dirt from the insides of it. Upon trying it it was not loud enough. I now have it as a collector item sitting on the shelf. A trip to the junk yard and a single Hella from a Merc with the correct el conmectors did the trick. It mounted perfectly in the spot of the old one. Sounds nice (the Merc had two Hellas) and saved me 1kg weight :-)

[Kagor 0]

In an attempt to save mine, I opened the two lids, top and bottom. Found the metal core, didn't know what to do, shut it close and replaced it with a random horn to pass the MOT

Let me know if anybody have refurbished one of these before.

[Eugene wilson 0]

i put the compressor in a bucket of acid pickle for my zinc plating kit over night ,it started working straight away then i soaked   the small holes with wd 40 for the bearings,might be worth a try,mine was seized up completely,eug.