Sherwood Brut 9110 Ambient Pressure Test

[scubapr1705]

Hi everyone.

I am just finishing an overhaul of this first stage and got to the part were I am supposed to the the "ambient pressure valve". Is there a workaround to perform this test that doesnt involve tool PN 20-750-500?

Here is the part of the manual that Iam talking about:

 

[scubapr1705]

@Couv or @rsingler any idea or recommendation?

 

[Couv]

Sorry, that is not a regulator I've serviced.

 

[axxel57]

The Schrader Valve mechanism is bullet prove if you have checked the function of the Schrader Valve. I checked the mechanism by pushing the diaphragm before I put on the cap.
That's for sure not as precise as the test recommended by Sherwood,, but you can feel if there is resistance or not.
I have serviced at least thirty of those 9110s, because one of my customers used it as fleet reg, and there has never been any problem about the compensation at depth of which I would know.
If you want to be sure, just put every time at service a new Schrader Valve into the 1st, the pressure transfer via the diaphragm is, as I said, bullet prove.
So no worries........

 

[scubapr1705]

Thanks @axxel57 my main concern is how much should I screw in the schrader valve so the diaphragm does its work.

The service manual says "Thread the schrader valve only until the end of the threaded portion of the valve is flush with the surface of the hole"

But for me, that doesnt work. If I leave it threaded until flush, it starts leaking air. So, I threaded it "until snug" but that is way in...

 

[axxel57]

Did you put in a new Schrader Valve?
There are basically three different types, one might be a bit longer than the other. I always tightened to snug and was okay.
It's years ago and my workshop is now in a container in the Caribbean, so I cannot check.....