Reconditioning old valve seats

[elmer fudd]

I've been away from SB for awhile now, but I've kept up on the vintage diving.

Anyway, the other day I stumbled into a great deal on three DH regs and one old SH. Two of the three, (RAM & DAAM), were working pretty well. The duckbills were long gone and the wagon wheel valves were bad, but other than that they breathed pretty nice. The other two, a blue label Healthways Scuba and a Voit MR12 had free flows.

Not having a spare Healthways valveseat, what I ended up doing was taking out the orifice, cleaning it up on the lathe with 0000 steel wool and then applying a smidge of fine valve lapping compound to the seat and pressing it up to the orifice for about 45 seconds while running the lathe. After cleaning and reassembling everything the free flow was completely gone and it was breathing tolerably. I won't say it was breathing nice because you have to suck quite a bit harder than you would with a RAM to get air. I'm guessing the cracking pressure is about 2.5", but I think that's due to a hard old diaphragm, the basic design and the fact that I haven't tuned it yet.

This wasn't the first fix that I tried. I originally tried just cleaning everything and replacing the o-rings, then shimming up the valve spring, etc... The thing that got rid of the free flow though was polishing both the orifice and the seat.

Since this worked out so well, I'm kind of wondering what other peoples experiences with this are.

 

[John C. Ratliff]

Elmer,

It's good to see you back. Anyway, the Healthways Scuba Blue Label did not have a really good venturi, but it had a small venturi IF you orient the levers so that they are at 90 degrees with the opening. You'll see beside the levels that there is a gap that allows air out into the box. If you put your finger over one side, you'll see that it actually does "shoot" air about at a 90 degree to the levers. So by orienting the levels to that 90 degree to the opening to the intake hose, you will get a bit of venturi effect. The other thing you really need to do is to get the levels as high as possible. The higher the levers, the easier this regulator will breath. I set them up until when the boxes are squeezed together, it free flows a bit due to pressure of the diaphragm on the levers. I then back it off just a hair until there is no free flow. This is higher than the "factory" setting, as I believe they recommended level with the top of the box. That's too low. If you get it up there, it will be a better breathing regulator, and a very smooth-breathing regulator too.

Concerning seats, I have refinished all kinds of HP seats by simply going to my knife sharpening stone (the very fine marble one) and using it to polish the seat. This works on many of the older USD HP seats. The Healthways seat is reversible, and by pushing it out you can get a "new" surface. I take the O-ring off the seat and lubricate it so that there will be no air getting by the outside of the seat too. The nylon valve plunger was the same for Healthways and Sportsways, and may now be available by some on this forum. I have never had a problem with simply cleaning or lightly polishing these valve plungers.

SeaRat

 

[herman]

I will have to keep that in mind. So far my HWs are OK. Bryan at VDH is most likey going to start producing replacement diaphragms for the HW double hose regs. I have been testing a prototype for him and it works great. He also has reproduction replacement HP seats for the DAAM and RAM.
I have not heard of anyone making (or NOS) HW seats (nylon part) but you never know. I have recently gotten some stock and am toying with making them. I also have a working (kinda ) HW single hose using modified AL and Apeks parts. I still need to do some tweeking but I think I am on to a replacement kit for them.

 

[elmer fudd]

I saw somewhere where somebody was selling NOS HW seats. VDH? They indicated they were the same as on Sportsways single hoses. I actually have one of those too, but I didn't want to cannibalize a working regulator.

Thanks for the tip about the venturi assist. I was completely unaware of that and I suspect that the last guy that serviced it was too. I plan on diving it on Tuesday, but I'm not sure how that will work out. I've got 4 double hose regs I need to check out now and I'm not sure which ones I'll get a chance to use. I think I've finally got my Northill completely squared away as well and it breathes surprisingly well now. I finally broke down and ordered one of the NOS seats from Vintage Scuba Supply without even being sure if it was correct or not.

When the VDH diaphragms come out I plan on ordering one.

 

[elmer fudd]

Here's the VDH link for the NOS HW seats.

Healthways/Sportsways High Pressure Seat [Healthways HP Seat] - $30.00 : Vintage Double Hose!, Your online source for all things related to vintage diving