Mistral DH Reg (~1959) and modern tanks

[Scuba Lawyer]

Yes! The IP rises when I turn the nut clockwise. I got it up to about 130 psi

Great!

As for the IP gauge leaking, yeah, you need to fix that.

What is leaking if you turn nut past 80psi? The IP gauge connection, or the 1st stage? If its just the IP gauge, the volcano orifice is not involved. If its the 1st stage that is leaking it could be a number of things. Fix your IP gauge connection first then see what happens when you raise IP to 135 or so.

If its the 2nd stage that is leaking when you raise the IP, loosen the retaining nut on the 2nd stage so the spring pushes the 2nd stage seat against the 2nd stage volcano orifice with full force. Once you get your IP adjusted to where you want it, slowly screw in the 2nd stage retaining nut until air escapes, then loosen it a 1/2 turn or so.

M

 

[JamesBon92007]

Unfortunately it's not only the gauge that's leaking. I adjusted it according to the instructions by turning it until it leaked and then backing it off until it no longer leaked and it breathes hard and the IP is only about 80 psi. I will try to follow your instructions and see how that goes. You are talking about the nut that surrounds the hex screw that adjusts the IP?

 

[Scuba Lawyer]

You are talking about the nut that surrounds the hex screw that adjusts the IP?

NO, definitely not. I'm talking about the nut on the second stage that holds in and adjusts the poppet stem that holds the LP seat. If you want to talk about it PM me your phone number and I'll be happy to walk you through it. Mark

 

[JamesBon92007]

NO, definitely not. I'm talking about the nut on the second stage that holds in and adjusts the poppet stem that holds the LP seat. If you want to talk about it PM me your phone number and I'll be happy to walk you through it. Mark

I've been incredibly busy and finally got back to the DAAM regulator. OK, I get it now. It's a lot like adjusting the second stage on an old Calypso. I didn't get the IP gauge on there yet so I may have to order the adaptor that was mentioned.

 

[CT-Rich]

Well, I finished working on the Mistral and she will be ready for sea trial. When the water has reached wetsuit temperatures. I broke it down as far as I was willing to go without permanent damage to certain parts (the adjustment wheel seems unlikely to move without damaging it). I learned quite a bit that can be applied to future projects. Reusing the c-clips to hold the two halves of the can together turned out to be much less of a hassle than I expected ( vise grips, applied judiciously are an amazing tool). To go with the regulator I picked up a steel 72 with J-valve and an almost new Aqua-Lung EZ-pack.

Total cost $70 for the regulator, $48 for the hoses, $30 for miscellaneous parts and $50 for the tank and backpack. My Trump bucks well spent.

 

[Scuba Lawyer]

Well, I finished working on the Mistral and she will be ready for sea trial. When the water has reached wetsuit temperatures. I broke it down as far as I was willing to go without permanent damage to certain parts (the adjustment wheel seems unlikely to move without damaging it). I learned quite a bit that can be applied to future projects. Reusing the c-clips to hold the two halves of the can together turned out to be much less of a hassle than I expected ( vise grips, applied judiciously are an amazing tool). To go with the regulator I picked up a steel 72 with J-valve and an almost new Aqua-Lung EZ-pack.

Total cost $70 for the regulator, $48 for the hoses, $30 for miscellaneous parts and $50 for the tank and backpack. My Trump bucks well spent.

Very nice! Those are great regs. I use mine 75% of my dives. Hope you replaced the only o-ring in the Mistral ( -006 o-ring ) as that is important. Just curious, but how did you adjust your lever height if the adjustment wheel didn't turn? It takes me an hour with the reg on a 300psi tank to find the "sweet spot" where breathing is practically effortless. I use that wheel a lot. Reg looks great!

 

[CT-Rich]

I am hoping that if it hasn’t needed too much adjustment in the first 60 years it will be good enough.
It breaths okay and doesn’t free flow. I can always break it down again if I am not happy with the outcome.

 

[Fish&beer]

Just my 2 cents worth, the Mistral & the USD KamEZPac is still my most favorite DH rig to dive with. It was my first scuba rig back in in 1969. Just a suggestion, when you set it up to dive, place the middle of the can even with the top of the pack. I have found that this is the best position of reg to pac placement to be the best for breathing with the Mistral, but you can find your best placement yourself with trial & error. (see photo below)

 

[AfterDark]

I am hoping that if it hasn’t needed too much adjustment in the first 60 years it will be good enough.
It breaths okay and doesn’t free flow. I can always break it down again if I am not happy with the outcome.

My Jet Air had a stuck wheel I soaked the adjustment wheel in PB Blaster over night to free it up.

Also does that bac-pac have a crotch strap? You should use one with that reg.
One reason dbl hose regs get a bad rap was divers not using a crotch strap to keep the tank and thus the can in the correct position.

 

[captain]

My Jet Air had a stuck wheel I soaked the adjustment wheel in PB Blaster over night to free it up.

Also does that bac-pac have a crotch strap? You should use one with that reg.
One reason dbl hose regs get a bad rap was divers not using a crotch strap to keep the tank and thus the can in the correct position.

And heat from a propane torch helps,