Mistral DH Reg (~1959) and modern tanks

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Ninja'd, lol
Also, if staying with the stock DA nozzle (first stage), search VDH forums on resurfacing the seat.... I just did one and it worked like a champ. Lock-up is crappy at first, but leave it pressurized for a while (some say overnight) and it seats in and starts locking up clean.
Respectfully
James
 
Remains of the duckbill may be under the hose.
 
A couple of things. First, at 300-500 psi tank pressure, adjust the first stage until it just leaks, then back it off a quarter turn. That should make I think breath much better.

Now, about the LP sear holder, if it is not leaking when you set it up, leave it alone.
SeaRat

Since it didn't seem to be breathing very easily I figured perhaps the LP seat was screwed down too tight.

Did there used to be duckbills in the mouthpiece that were replaced with wagonwheels? Or was it always wagonwheels? This is my first doublehose but for some reason I thought they had more than one duckbill valve.
 
Since it didn't seem to be breathing very easily I figured perhaps the LP seat was screwed down too tight.

Did there used to be duckbills in the mouthpiece that were replaced with wagonwheels? Or was it always wagonwheels? This is my first doublehose but for some reason I thought they had more than one duckbill valve.

There was always a duckbill in the can. Early hoses did not have wagon wheels and were a pain to clear when flooded. Next came the Hope Page mouthpiece with wagon wheels and eventually all double hoses had the valves in the mouthpiece that made clearing the hoses easier. You still need the duckbill though (or a duckbill eliminator valve) otherwise the exhaust hose floods and makes exhalation more work.
 
Since it didn't seem to be breathing very easily I figured perhaps the LP seat was screwed down too tight.

Did there used to be duckbills in the mouthpiece that were replaced with wagonwheels? Or was it always wagonwheels? This is my first doublehose but for some reason I thought they had more than one duckbill valve.
No, the tightening of the seat holder would increase the Spring tension, but that's not the screw on the top, that's the entire unit. I'll have to check my references to see about the seat holder. Do you have the U.S. Navy Diving Manual from 1970, which goes over the service on the DA Aquamaster?

Concerning the duckbills, they have always been on the box. The original mouthpiece for the DA Aqualung (the Broxton regulator the preceded the DA Aquamaster) did not originally have any check valves in the mouthpiece. The DA Aquamaster always had mushroom valves in the "Klear-EZ" straight mouthpiece, and later the curved mouthpiece. But, when I went through the U.S. Naval School for Underwater Swimmers, they had removed these valves. When we got to the maintenance of these regulators, some of us surreptitiously inserted the valves into the wagon wheels, which made pool harassment a bit easier.

SeaRat

PS, I've posted some photos too, and a repair manual for the Mistral. I don't have the Aquamaster up yet.

PS1, I've found the Aquamaster manual, but I need you to PM me your e-mail. It is in Google Drive, and that way I can allow you access to it to download it.
 

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  • Aqualung Repair Manual for Mistral.pdf
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No, the tightening of the seat holder would increase the Spring tension, but that's not the screw on the top, that's the entire unit. I'll have to check my references to see about the seat holder. Do you have the U.S. Navy Diving Manual from 1970, which goes over the service on the DA Aquamaster?

Concerning the duckbills, they have always been on the box. The original mouthpiece for the DA Aqualung (the Broxton regulator the preceded the DA Aquamaster) did not originally have any check valves in the mouthpiece. The DA Aquamaster always had mushroom valves in the "Klear-EZ" straight mouthpiece, and later the curved mouthpiece. But, when I went through the U.S. Naval School for Underwater Swimmers, they had removed these valves. When we got to the maintenance of these regulators, some of us surreptitiously inserted the valves into the wagon wheels, which made pool harassment a bit easier.

SeaRat

PS, I've posted some photos too, and a repair manual for the Mistral. I don't have the Aquamaster up yet.

PS1, I've found the Aquamaster manual, but I need you to PM me your e-mail. It is in Google Drive, and that way I can allow you access to it to download it.

Let's see, "counter-clockwise is tighter (stops it from leaking)", right?

So, there were two duckbills, just not on the mouthpiece? That seems to be what's way in the back of my mind (a scary place) somewhere.

captain emailed me a manual but I'm not sure what year it is--I haven't looked at it yet. I've been working on stuff all winter and finally got a chance to see how things worked today. I serviced my old Calypso single-hose and added a shim to the first stage and wow, I can't believe how well it breathes now. I bought it somewhere around 1973 and dove the hell out of it.

It's about time I got a double-hose reg. When I took my original NAUI course some were still teaching with double-hose, and others had just started using single-hose regs. My instructor had the single-hose regs. He even had a Sea-Vue gauge on his setup. The rest of us had to rely upon paying attention and being in good enough shape to snorkel back to shore :wink:

Thanks everyone for all the great info!
 
Let's see, "counter-clockwise is tighter (stops it from leaking)", right?

So, there were two duckbills, just not on the mouthpiece? That seems to be what what in the back of my mind (a scary place) somewhere.

captain emailed me a manual but I'm not sure what year it is--I haven't looked at it yet. I've been working on stuff all winter and finally got a chance to see how things worked today. I serviced my old Calypso single-hose and added a shim to the first stage and wow, I can't believe how well it breathes now. I bought it somewhere around 1973 and dove the hell out of it.

It's about time I got a double-hose reg. When I took my original NAUI course some were still teaching with double-hose, and others had just started using single-hose regs. My instructor had the single-hose regs. He even had a Sea-Vue gauge on his setup. The rest of us had to rely upon paying attention and being in good enough shape to snorkel back to shore :wink:

Thanks everyone for all the great info!
Mouthpiece has 2 non-return valves (mushroom style), then the exhaust can has the duckbill to keep water from flooding the exhaust hose. Only one actual duckbill involved. If you'd like, I can take pictures and post.
Respectfully
James
 
Go to the VDH forums and do some reading and all will be revealed.
 
My DW Mistral arrived the other day. It came with the mouth piece and the wagon wheels. I ordered the flanges for the wagon wheels and hoses, along with a new filter and retainer. I took the cover off the can and the duck bill and the diaphragm both look to be in good condition. and I did some test breaths off a tank and it felt good. I decided not to do a complete breakdown of the assembly unless people think that is critical. I did skip the Band clamp, $25 seemed pricey for something I might get in a hardware store. I am not sure it came with the correct yoke screw because it was too short for my vintage German twin 50s.
 
https://www.shearwater.com/products/swift/

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