I read through this and I am trying to understand, why are we taking our regulator apart? Did I miss the reason? And what is the regulator again?
To remove a stuck diaphragm, you could just blow forcefully into the mouthpiece. That usually pops it out. Especially with warm, soapy water.
Yes, by all means, remove theLP hose. The hose attaches to the low pressure orifice/knife edge which screws into the regulator body. You will need to restrain the orifice with one wrench and break the hose (nut) with the other. Then remove the LP orifice from the regulator housing. When you do so it is customary to depress the lever. Depressing the lever raises the LP seat from the orifice preventing the knife edge of the orifice from being damaged and possibly cutting into the LP seat material as it is rotated to screw out or in.
The 120 psi is not terribly low, especially if the regulator is used for cold water diving but I would probably bump the IP up to 135 psi or close but no higher. That is a first stage adjustment.
Since it is apart, put in a new seat.
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