Slight thread
Lucca,
The honking you are describing (coming from the 2nd stage) may or may not be corrected by replacing the 2nd stage diaphragm.
As mentioned, the honking is often caused by the diaphragm resonating during inhalation. Many different 2nd stages
can do this, and it is not often a safety issue.
If this is happening
underwater (less common than on the surface) is could be a problem with the
lever height adjustment in the 2nd stage. This is something a
competent Mares tech can check quickly, but it really needs to be tested with the regulator connected to a tank and pressurized.
Properly adjusted Mares 2nd stages will produce a slight "click" or "tap" sound if you gently shake the 2nd stage when the regulator is connected to a tank and pressurized... But there will be
no clicking sound when the regulator is unpressurized. The "click" is the sound of the demand lever hitting the bottom of the diaphragm, and indicates that there is just a tiny bit of "slack" or play in the demand lever. It take a little experience to know how
much of a "click" you should hear.... it should not be a loud "clack", which would indicate the demand lever has too much free play, but you should hear it lightly tap the diaphragm, otherwise it does not have enough free play and the regulator will be too sensitive...
When I adjust my Mares 2nd stages, I remove all free play from the lever (by raising the lever height) until the "click" disappears (with the regulator pressurized), then lower the demand lever until the "click" just barely returns.
Rotating the 2nd stage diaphragm or flipping the 2nd stage spring are also possible solutions. Unless you are comfortable working on your own regulator (and understand exactly what you are doing) this is something you will probably need a regulator tech to do for you.
Good luck.
