cleaning old first stages

[duppy_conquerer]

Hello, so I've got an old Sherwood first stage that i found in a dive shop basement. I didn't have a whole lot of tools or knowledge at my disposal, so i checked the intermediate pressure, the cracking pressure, & inspected for any leaks. All of that looks fine, however the filter is wrecked and there's a a lot of salty crap built up in all the ports on the first stage.

Somebody suggested I remove the hoses and submerge the whole first stage in vinegar? Unfortunately my regulator inspecting knowledge pretty much ends at checking the IP so would welcome any advice on the best way to clean it.

 

[Hickdive]

All immersing the whole thing in vinegar will do is remove the salt, remove lubrication and degrade the O rings.

If the filter shows a lot of filth then it's a fair bet the interior is in pretty poor state too.

It's probably not worth the time and effort to get it professionally serviced which is why it was probably chucked in a corner and forgotten. On the other hand it probably isn't worth the investment in tools to do it properly on your own.

I'd fling it on eBay with the clear caveat that it is not dive-able and needs a proper service, someone with the tools and experience will probably snap it up.

 

[tstormdiver]

I would agree. If you don't know when the last service was, there could be components that are not in good shape, but haven't given up yet. In the middle of a dive, is not the best of places to be during a catastrophic failure. I would recommend either getting it serviced, servicing it yourself (Sherwoods are pretty simple, as far as regulators go), if you can find a guide, tools & parts or as mentioned above selling it as undivable until serviced.

 

[halocline]

If you have an interest in learning how to work on regulators this would be a great one to start with. The tools required are minimal and parts are readily available inexpensively. I'd start with the Vance Harlow book on regulator repair. That book will have a a schematic of this first stage if it's one of the more common sherwood models.

I have to agree that the idea of removing the plugs and soaking it is not a good one, but to be honest, rebuilding is not much more complicated; you just have to disassemble it, remove the o-rings and seat, and then soak it in vinegar, then re-assemble it with new o-rings and a seat. If it currently holds IP well and doesn't leak, it's probably okay in the ambient chamber (that's where most of the corrosion would likely be) but you don't know until it comes apart. If you want to test it some more, put it on a tank, pressurize, and let it sit for a few hours, tapping the purge every so often. Those old sherwoods are remarkably tough.

If you don't have any interest in learning about regulator repair, you might give it to someone who does.

 

[duppy_conquerer]

Thanks for all the replies!

If you have an interest in learning how to work on regulators this would be a great one to start with. The tools required are minimal and parts are readily available inexpensively. I'd start with the Vance Harlow book on regulator repair. That book will have a a schematic of this first stage if it's one of the more common sherwood models.

Yeah long term i would like to learn to service them myself, so i reckon I'll hold off till I get the Vance Harlow book - seems to be the one everybody recommends!

 

[tbone1004]

keep in mind, when they say soak in vinegar, a diluted vinegar solution in an ultrasonic cleaner is the best option, and make sure if you soak it in vinegar, you don't do it for more than 5 minutes, then rinse it very well with running water to blow the salt off, then soak it for a few minutes in a bath with baking soda to neutralize the acid which can eat away at the chrome. The rest of the tools aren't all that expensive, so it certainly is worth pulling apart and figuring out how it works.

 

[keyshunter]

Assuming that you are talking about the inlet filter, that one is easy to find and replace. There is another filter on older Sherwoods which is integral with the piston that can a greater problem. It is a scintered filter which is part of their rather unique air bleed system. I have tried various methods of unblocking these, with very limited success. If this filter is blocked, you will probably have to replace the piston. When pressurized, if this filter is open, there will be a very small amount of air leaking from the black plug on the exterior near the port plugs. At the surface, the reg will still breath with this filter blocked, but will get progressively harder to breath as you go deeper.