Sherwood Regulator Identification

[KeithG]

The first stage would have been used on several models back then. The second stage that has no markings is likely a blizzard or an oasis. they were very similar with a few differences. the Blizzard would have a Teflon coated lever and the intermediate pressure would be around 125psi verses around 145psi for the oasis.

It was a later version of Blizzard SRB3900 that used the lower IP of 120 to 135 "to resist freezing in cold water diving". It also had a different first stage (edit) than pictured by the OP.

 

[JamesBon92007]

I owned a Sherwood in the past but I'm not a Sherwood guru. However if I'm not mistaken Sherwood used the same basic 1st stage for several different sets (Brut, Magnum, Shadow, Maximus). It seems to me that the differences are mainly in the 2nd stage design.

... and why wouldn't they? It's one of the most robust 1st stage designs in the history of our sport.

does this 1st stage have a "dry bleed"? The dry bleed looks like a little rubber stopper in the 1st stage. When the regulator is charged it will let out a small stream of bubbles. This is normal and it is necessary because the 1st stage design is a piston. The advantage of a piston regulator is that it only has 1 moving bit and it's pretty much bulletproof, but most piston regulators let water inside in order to balance the pressures. Sherwood found a way to make a piston regulator that stays dry on the inside so it is much less prone to freezing and much less vulnerable to pollutants in the water.

The bleed, as I said, looks like a bit of a black rubber cap. This cap is not normally not replaced with service so if it has one and it's been laying around for a long time then get it carefully inspected and/or replaced when you take it for service.

Same goes for hoses. If it's been laying around for a long time, consider getting the hoses replaced as a precaution. Better safe than sorry.

R..

I've been diving with Sherwoods since the mid-80s and never felt a need for anything "more." I have taken apart the first stage and it always looks brand new inside. I own three Magnums (one is a recent acquisition) and they have worked almost flawlessly for decades. I did have to replace the O-Ring for the valve seat on the second stage on one of them. I also had to adjust the tension on the valve seat once or twice. If I had maintained them just a little better then the O-Ring problem would probably not have occurred. I never dive deeper than about 90-100 feet so I can't comment on how they perform deeper, but I have found them to be extremely reliable and easy to service. Now I make sure to rinse and dry them thoroughly (it's so easy to unscrew the diaphragm on the second stage) and give the metal parts a very light coating of silicone. They also have the little pin that takes the pressure off the valve seat which helps to keep it from becoming deformed. And if it does you can flip it over once but often just turning the screw inside the air inlet about 1/8 turn will take care of any leaking without effecting performance. Parts appear to be available on eBay.

 

[JamesBon92007]

Also, a tip to prevent sea water entry into the dry bleed system.
After your dive, soak the reg charged to a tank. I use a cooler and my bailout bottle. After soaking, remove and turn tank valve off. Do not purge the reg...the dry bleed system will discharge the air and dry out the bleed system. This will take a bit mind you. Salt water can get into the system if not cleaned/purged and will kill the little filter that is on the piston. Ask me how I know.

I have to run right now but wanted to post a reply so I won't forget. I'm not completely clear about exactly what you are doing here or why it is necessary. Why it is even necessary to "soak" the first stage? If the plastic cap is in place there is no place for water to enter, is there? I thought the bleed valve was a one-way valve.

I'll be back.

 

[KeithG]

I have to run right now but wanted to post a reply so I won't forget. I'm not completely clear about exactly what you are doing here or why it is necessary. Why it is even necessary to "soak" the first stage? If the plastic cap is in place there is no place for water to enter, is there? I thought the bleed valve was a one-way valve.

I'll be back.

If you are salt water diving then you will have salt residue on the outside of the reg. This should be removed.

If you look at used regs for sale on eBay, every now and then you will see a first stage that has greenish dots / crusty bits from salt attacking the reg.

 

[JamesBon92007]

If you are salt water diving then you will have salt residue on the outside of the reg. This should be removed.

If you look at used regs for sale on eBay, every now and then you will see a first stage that has greenish dots / crusty bits from salt attacking the reg.

Thanks. I just rinse the outside thoroughly. Mine did not come with an O-Ring in the little plastic dust cap so I added one so water won't get inside while rinsing. I very thoroughly rinse the inside of the second stage and unscrew the diaphragm to let it dry.

I bought a first stage and a second stage on eBay and both looked like they had never been used

I got the impression from Ghetto Diver's post that water could get into the first stage through the bleed valve if the reg is not charged with compressed air. Is that what you/he meant?

 

[KeithG]

...I got the impression from Ghetto Diver's post that water could get into the first stage through the bleed valve if the reg is not charged with compressed air. Is that what you/he meant?

Not what I meant. I have soaked our regs unpressurized for 30 years. The reg rinse barrels at the Divi in Bonaire are about 3 feet tall. I have never had a problem with water intrusion so the bleed valve works to 3fsw. But it will fail at some point. How deep? I have no idea.

 

[JamesBon92007]

OK, thanks!

 

[Ghetto Diver]

I got the impression from Ghetto Diver's post that water could get into the first stage through the bleed valve if the reg is not charged with compressed air. Is that what you/he meant?

Yes, that is what I am referring to, I have seen a bit of corrosion develop underneath the rubber plug on some, so water can penetrate the underside. I have purchased a couple that had clear signs of SW damage. There was a trail of corrosion from dry bleed vent all the way to the piston. Filter on piston toast. The rubber plug was in good condition though and reuse on another stage.
No one told me to do my method, just something I do after these observations. It's not like I am adding a step in the soak process. Just sharing and caring....

Also, I didn't pay attention when I originally posted and did not notice this is the mfg's section. Sorry Sherwood bro's!
My first regulator purchase was in '84 and guess what, it was a Brut.

 

[JamesBon92007]

OK, thanks. So far none of mine appear corroded at the bleed valve but that might be kinda tricky to check. Yes, pressurizing the first stage while rinsing would be the logical solution but I've never heard of doing that before. I only rinse mine enough to get the salt water off and if it isn't clean and bright and shiny all over I take it apart to clean it. I probably only have it submerged about five seconds. Now I'm thinking I should at least connect it to a tank and pressurize it for a minute or two after rinsing. I would need to get a much bigger rinse tank in order to get a steel 72 in there too. I don't have any pony bottles or Spare Air or whatever. I do have a CO2 tank if I ever find a good deal on a valve for it

Let's see, in '84 I was probably on about my fourth regulator purchase, which was a Magnum It replaced my Calypso which is now my very first octopus.

 

[Ghetto Diver]

You could just rinse as you do while connected to your tank. Once done, turn tank valve off, but do not purge the regulator and let the bleed system do it's thing [no soak].