Question: '57 Mistral DW

[buckled plates]

I have a friend who's acquired a '57 Mistral DW. He's a vintage gear junkie and has restored the Mistral to good working order but, whenever he dives it, it winds up with a few ounces of water in the top box. The water doesn't appear to be infiltrating from the "wagon wheel," he says, and the diaphragm is in good condition (but not original). Also, there's some there's some minor pitting on the sealing rim of the top box (obviously the result of earlier water penetration and poor maintenance. Questions: Is such leakage unusual or a problem? What is a good solution for repairing the minor pitting on the sealing rim? He's tightened the band clamps as tight as possible. Is it possible that's the problem?

He'd ask the questions himself, but he's old-school and doesn't have aScubaBoard account, internet service, or even a cell phone. We started diving together in the '60's, and he only recently retired his '75 USD Conshelf regulator, so you get the idea!

Thanks for any thoughts and help!

 

[Sam Miller III]

Warped cans ?
Pitting on edges of cans?

Pin hole in diaphragm ?
(on the original regulator "Swallowing the diaphragm was common)

"Band Clamps " were NOT made for this regulator -- change to "cir clips"
( I have a supply of original cir clips of needed)

SDM

Question for you
1967
you began diving- no training

what book did you read in 1967?
where did you acquire your equipment in 1967 ?
where did you find a compressor in 1967?

sdm

 

[herman]

There are several places a leak can occur, but to be honest, I don't worry about a tiny amount of water in the cans, I just flush them after diving.
Some possible places for water intrusion are a tiny hole in the supply hose, usually near the horn. It is not uncommon for a small hole to be cut/wear due to the edge of the horn cutting the hose. A close inspection while stretching the hose will usually show it. With the Mistral, a loose yoke nut or a defective body gasket can cause the leaks. Slightly out of round can horn or loose hose clamps can also let water in, as will damage to the can's sealing surface.
And it might be as simple as some water leaks past the wagon wheel valves and when he removes the hoses, the water runs down the hose into the cans. They are by no means perfect seals. If there is water in the mouthpiece it will run into the hoses if he turns on his side or back.

As for the band clamp not being original, while not standard on the reg, band clamps were sold as an option for the DA, DW and DY regs in 1957...$1.95, page 4 of the 57 catalog.

 

[John C. Ratliff]

All of the ideas above are good ones. I have found that if you place your thumb over the tank connection (the hole with the sintered filter under the yolk), and inhale hard on the mouthpiece, you'll get a hiss where any leak originates. If you cannot find a leak this way, suspect the mushroom valves on the wagon wheel. This small amount of water is not important for safety, unless you are diving under ice or it stays there between dives for days or weeks.

SeaRat

 

[captain]

Look for a small split in the inhalation hose where it meets the nozzle on the can. They can be hard to spot unless you bend and stretch the hose.