I just fixed the by Wolo 419 when it was only making a single-tone sound, instead of a dual-tone the way it is supposed to. Since I havenít really seen any explicit instructions on how to do this, so I thought I might share these with other people having this same problem.
First of all, I would like to say that I believe the idea of hitting the horn with a mallet or tapping on it with a screwdriver is probably not a good ideaódespite what the manufacturer and others may say. I tried it, and it did not work.
The problem with the horn is that one or both of the diaphragms are completely or partially clogged with dust; possibly quite minute particles of dust. The small diaphragm hole openings are underneath the round, loosely fitting plastic caps found on each side of the Stebel/Wolo. You need to carefully pop these off to expose the small diaphragm hole openings in the underlying metal base. A pocket knife, carefully wedged between the plastic cap and and the metal base, while rotating the cap with your other hand, worked nicely for me.
Other than a pocket knife what you need is an air hose driven by a air compressor with one of those airblow gun attachments, preferably with a rubber tip, so you can press it up to each one of those diaphragm hole openings while sounding the horn to blow out the minute debris causing the problem.
Youíll test the horn by sounding the horn without blowing the compressed air out of it. Note: The imbedded link to the Harbor Freight blower attachment is actually the one I used. It actually included a rubber tip not shown in the picture.
Mine only had one side(diaphragm) clogged. To determine which diaphragm was clogged, I simply but my finger over each of the hole openings one at a time while sounding the horn. When both tones sounded, I knew the hole that I had my finger over was the one that was not clogged. Thatís because shutting of the air flow through that hole forced air through the partially clogged hole, which, if sounded the horn long enough, might have corrected the problem, but I instead chose to concentrate air through the clogged hole with the blower attachment while sounding the horn. This did the trick.
I also wiped around the metal base with a white piece of bed sheet and was surprised at how much dust was there that I did not immediately notice. Wiped out the inside of the plastic diaphragm caps, too.
Not water or chemicals, just a clean, soft, piece of bed sheeting.
Hope this helps anyone else experiencing this problem.
That's good feedback...
I also saw someone suggest wrapping a piece of very fine netting fabric around the air intake to possibly prevent what you've found.
2017 Pearl White 650[/B]
AdventureTech lowering links and GPS mount
AdventureTech +2" SS braided brake line
GPI spools, SW Motech risers
Givi XS307 Tanklock bag and Givi 46L top case
Suzuki hard case saddlebags