Twin Yoke overhaul

[treasureman]

Does any one on this forum have the knowledge and ability to poverhaul a USD solid twin tank yoke. Mine is getting stiff to open and close, and I think the reserve is not working because when the pressure drops down to 500 or less, there is no extra breathing effort... in other words, you nebver know you are on reserve until that last gulp of air.

Please pm me to let me klnow or respond on line

[time2dive]

I do normal valves all of the time. I have some parts for USD valves and some J valve parts, it depends on the valve. I have a vintage repair manual enroute so I will have a better idea of what parts I have for what valves. I receiently rebuilt one of my three piece valves only to find that it was cracked and only good for parts. So depending one what valve you have I MAY be able to help.

[1969ivan1]

MARVEL sells all the rebuild parts for that manifold as they still sell the manifold. The seat on it is very different from the other usd seats I have seen. My local LDS could not get me one so it was MARVEL to the rescue for me. I love that manifold!

[treasureman]

Thanks guys, I knew i could count on the vintage divers for help. Is there a part number for the kit for the solid twin yoke, and is there anyone who has the tools to do the overhaul?

As well what is the url for Marvel

[Bryan]

I don't know for sure but Tom (Captain) may be some help if Tim and Robs suggestions don't pan out....

[pescador775]

I use that manifold. Bought a couple on EBay. I don't remember anything special about the internals. I always disassemble a used valve for inspection and this job was routine. No special tools that I can recall. Whenever removing a bonnet it is good to use a box wrench if possible, never a crescent wrench. Disassembly is probably easiest if left installed on the tanks. Otherwise, a proper vise is needed. The Nemrod manifold requires a special tool for the bonnet but that is the only case I can recall. All these reserve mechanisms appear to be different in some details. If I recall correctly, the bar manifold reserve valve seat just unscrews. The only reserve I have seen which is not repairable is the old Healthways which is encapsulated. The module is easy to remove for inspection but cannot be disassembled. They seem to last, though. As was pointed out above, the antique USD manifold with 1/2 inch pipe neck featured a plug which held the reserve poppet against a spring. Some of these plugs, which are delicate, were sealed with a gasket and are easy to remove. Others are metal to metal and are a bitch to remove. Usually, if corroded at all, they crack.

[Sea Explorer]

Any Aqualung dealer should be able to get the parts. The manifolds are still in production and they are still in the AL repair manual last I checked. They are virtually indestructible. -Ryan

[treasureman]

The LDs where i am, is reluctant to get into the manifold because of age.

[pescador775]

Treasureman, some old manifolds are subject to being damaged. That may happen when something is held fast by corrosion. Maybe your LDS is scared of that. The USD bar manifold is strong as a safe, has few moving parts, and I had no difficulty disassembling the two purchased on EBay. There is a special tool for the nut which holds the plastic knobs. I forgot to mention because this tool is not special to me. It is used on virtually every valve and manifold. I made a tool which looks like a wide, flat blade screwdriver with a slot in the middle. I ground it out of a piece of bar stock. Other than that, nothing but a couple of wrenches. The manifold is as easy to work on as a kitchen faucet. If you obtain the parts from Marvel, I can think of no reason why a shop would not help with overhaul.

[seakrakken]

Marvel indicates on their site that the parts kit for this manifold is for sale to Govt and Military only. Is that true or is that a smoke screen? If it is for sale does anyone know how much they want for the kit? I'm asking because I have one and I would like to rebuild it before I try to use it.

[treasureman]

geting the parts would be wise to do before any attemtp at overhaul. Anyone have experience with Marvel getting this parts kit

[pescador775]

Here is what Northeast Scuba Supply has to say about the manifold kit:

]Dennis, hi I just spoke to aqualung they have as many of those suckers as you would like they are $45.00 for the kit. Give me a call at 610-631-2288 if you would like to order. See ya John

[seakrakken]

That's great! Do I order it directly from them myself or do I need to order it through you?

[crimediver]

The agency I work for has dealt with Mar-Vel, (I think that's how it is spelled). We had to jump through a couple of hoops to purchase such as registering, letterhead, tax exempt number, etc. I think you may be right that they prefer to deal only with miltary, Govt. or possibly commercial operations. I know the do have about anything you need, including the solid USD J-valve manifold, USD military web harnesses for aluminum 80 doubles, etc. Also have a selection of horsecollars such as USD and Seatec. I find their prices a little steep.

[pescador775]

Treasury guy, give John a call. He runs a retail dive shop and mail order business. Have credit card ready. Brace yourself, Crazy John talks faster than most people listen. He is reputable and well known by mixed gas divers.