Calypso IV unable to adjust IP

[Bingjet]

I just rebuilt my Calypso IV first stage regulator. The IP measured ~170 PSI prior to and after my rebuild and it is not responsive to adjustment. I smoothed some some light indications going around the piston but this did not influence the issue. I did purchase another Calypso IV from ebay which I also rebuilt and it works fine but I would like to get my original regulator working. I thought about swapping out parts from the good one to isolate the problem but I really do not want to take the chance of damaging the good one...​

Any recommendations?​

 

[GJC]

Need more info.

Does adjusting make any change in IP? If not your springs may be bad or sticking.

Does IP respond briskly and hold or creep?
Could be bad seat or piston edge.

Is main spring in good condition or corroded?

 

[Bingjet]

Adjusting has very little if any change relative to IP. I can feel the tension change while turning. THX

 

[GJC]

Is there corrosion where large piston o ring seals inside shaft? Maybe piston getting stuck

 

[Bingjet]

No visible corrosion but I agree that this may be the area of concern.

 

[GJC]

How does IP change with breathing cycles?

Not knowing your background, have to ask an obvious question, o rings are lubed right?

Don't be too proud to just give up on it eventually. Some of the old vintage regulators just have a gremlin in there that just won't leave no matter what you do and there are a lot of others you can find that are inexpensive that don't have a gremlin in them.

 

[Bingjet]

I removed one of two shims and lightly smoothed the castle side of the seat assembly. It was possible to set ~135 PSI IP but the adjustment screw is almost all of the way in.

 

[GJC]

I think there should only be 1 washer against the main spring or none. It's not an adjustment shim. It may not belong in your reg and you may be able to adjust better with it out.

I have done Calypso J and Calypso III. One J diagram shows a washer, one doesn't. The III shows no washer. I can't find a diagram for a Calypso IV.

 

[John C. Ratliff]

I removed one of two shims and lightly smoothed the castle side of the seat assembly. It was possible to set ~135 PSI IP but the adjustment screw is almost all of the way in.

It is possible that someone did not realize that the Calypso piston regulators had this adjustment feature, and tried Scubapro shims on the Calypso in the past.

SeaRat

 

[ofg-1]

I have 6 of these I bought when I was actually teaching in the mid 70's. There was a recall of the main springs back then, they had a batch that was brittle and had a few break while in use. I am not sure how to tell which is which. I have taken my springs and compressed them in a vice to lower IP when the adjustment did not work. I just compressed them a bit and let them sit a couple of days. If you can get down to 135, it should adjust out on the second stage.