DIY Regulator Maintenance Discussion: Aqualung

This thread will be for the discussion of DIY regulator maintenance for Aqualung and US Divers brands. It will be similar to the MARES thread I did last year concerning regulator maintenance. I thought I would share what I am doing and let others chime in about what they are doing. The goal is to do this right without having to hunt down OEM service kits and/or Replacement parts which are difficult to obtain for the DIYer. Please feel free to add to the thread, correct me, or otherwise participate. As usual...standard disclaimer, I am not responsible for anything that happens as a result of you reading this. I only want to share what I am doing, not give you instructions for you to use to injure or kill yourself. Do so at your own risk.
I will attempt to provide information for what all of the parts are in the service kits and where to source them from normal suppliers that anyone can order from whenever I can find them. I will also include some of these items that can be sourced from Trident. Many shops will sell Trident parts to customers, even if they will not sell the OEM parts kits. I have seen OEM parts kits and Trident parts for sale on eBay. Vintage Scuba - Vintage Scuba Gear at Vintage Double Hose is also a good source for parts and they sell to the general public. Please contribute alternate sources for parts if you know of them.

At the moment, I will not be doing a step by step “how to” because that is easily covered in the fine publications by Airspeed press and Scuba Tools. They are great books, worth the money, get them. Support the people who are making a lot of the DIY activities possible. I will start with the old style Titan 1st stage, Titan 2nd stage, and Titan LX 2nd stage simply because I have some and worked on them recently. I also have some Conshelf SE2 and Micra types so may get to them next…or someone else can contribute as well with any info they would like to offer. Or you can suggest some specific model if you like….maybe I’ll get around to it, maybe not.

~Chris

Titan 1st stage: AL part #103111 Discontinued older type Titan 1st stage.

This 1st stage is fairly common and very simple to work on. The OEM rebuild kit is identified as Aqualung part #900001 "Overhaul Kit". This kit is used for the Yoke type configuration. DIN configurations include some additional O-rings not in the Overhaul kit. I will include the AL part numbers for them but since I don’t have any of them on hand I can’t size them up…Anyone have the DIN version and can give up some info…



Kit Parts
105940 "HP Seat" 1EA
105106 "Filter" 1EA
863051 "Filter retainer" or “Circlip” 1EA
845095 "Filter washer" 4EA or 124627 "Metallic washer" 1EA
119129 "Backup ring" 1EA or 828005 "Backup ring" 1EA
103425 "Diaphragm kit" 1EA which includes…the Diaphragm and Thrust washer
Kit O-Rings
820080 "O-Ring" 1EA
820120 "O-Ring" 1EA
820094 "O-Ring" 1EA
957004 "O-Ring" 1EA
820011 "O-Ring" 3EA
820038 "O-Ring" 1EA
DIN Configuration O-Rings not in the kit
820094 "O-Ring" 1EA
820072 "O-Ring" 1EA
820017 "O-Ring" 1EA

105940 "HP Seat" 1EA
This seat is identical to the Mares seat Part # 46185002 used in the MR12, non SCS type V16 , some of the MR22 types and others. This seat is also suitably replaced by the 3rd party Trident part # A-244( I paid $11 ea the last time I bought from a Trident dealer) . Below are pictures of all of these side by side for comparison. They are in order from left to right, the old MARES HP seat, the new MARES HP seat, the Aqualung HP seat, and the Trident HP seat. You can also get this part from Vintage double hose here for $15 ea …Shop Online




Sometimes the HP seat requires replacement, sometimes not. If it locks up at the correct IP pressure, I continue to use it. If not, I change it.

105106 "Filter" 1EA
This item is a simple disc type SS sintered filter, 1/2" diameter 1/16" thick. I replace these every time I service a reg. They are cheap and it is what filters the air from your tank…why not change it. I found suitable replacements at McMaster Carr as part # 9446T32 McMaster-Carr
I used the 5 micron type. I couldn’t find anyone who knows what is typical pore size for SCUBA regs. Although, I think that 5 microns is way more filtration than what most SCUBA manufacturers are using. There isn't really a restriction at our flow rates so why not have the extra filtration. They are cheap enough at $11 or so for QTY 6. Trident sells a good replacement option as part # AA71.I also found suitable replacements at Northeast SCUBA supply buy Flat Filter and Star Retainer at northeastscubasupply.com - Regulators - Regulator Service Kits - Flat Filter and Star Retainer - Northeast Scuba Supply. I also found them at vintage double hose here…Shop Online along with the next item(124627) for $5 ea. Additionally, it is the same part as the Mares 46185014 "Sintered Filter"

845095 "Filter washer" 4EA or 124627 "Metallic washer" 1EA
See the listing from vintage double hose on the item above that includes this washer. The 845095 version of this washer is a nylon washer and Aqualung states that it is not compatible with Nitrox. For Nitrox use, Aqualung states to use the 124627 which is a stainless steel washer. Essentially, use any SS washer with a ½” outside diameter(matches the filter) I would use one with the largest I.D. that I could find. Honestly I don’t see these needing replacement very often.

863051 "Filter retainer" or “Circlip” 1EA
This item is basically just an HO type Internal SS Snap ring. It is easily available from McMaster Carr as part # 91580A151 McMaster-Carr . you can also get it from vintage double hose here for $1 ea …Shop Online
This item is also the same as the Mares Part # 46185015

119129 "Backup ring" 1EA or 828005 "Backup ring" 1EA
The 119129 backup ring is a black rubber backup ring used in many of the Aqualung 1^st stages. It seems to be fine in most applications. About half of the regs I have taken apart have had this one installed and it is what comes with the kit. The 828005 backup ring appears to be the white PFTE version of that same item and I have seen it included in the Military version of this kit. I view them as interchangeable. I have and use both but I prefer the PFTE ones, I couldn’t say why…just preference. Here are sources for both. McMaster-Carr . The 119129 is available from McMaster-Carr as their standard back up ring Part #5288T111. The 828005 backup ring a simple PFTE split Back-up ring for AS568A O-Ring size 005. You can easily get this from McMaster Carr as well and it is identified as Part # 9560K31. The strange thing is that this backs up a size -006 O-Ring but they do use the -005 back up ring. They use it because it works and it fits. Pictures of the OEM kit part and the McMaster part that I call for side by side and one on top of the other are below. You can also find this part at Vintage double hose here for $3 ea…Shop Online



I change the backup ring, everytime I service the reg.

13425 "Diaphragm kit" 1EA which includes…the Diaphragm and Thrust washer.
I have not found the need to replace these at every service. I was able to get suitable replacements when I did replace them from Trident. The Diaphragm is part # A163 and the Thrust washer is part #A171. Aqualung uses basically the same diaphragm (exact same diameter and almost the same thickness)… but with fabric sandwiched between the layers of EPDM. You can make your own if you are adventurous and want to spend some money on material like this… Cloth Inserted Fabric Reinforced EPDM Rubber | Rubber Sheet Roll Or…I have made and used replacement diaphragms out of sheet EPDM(.06 thick) just like the Trident ones are made of by carving it out with an exacto knife.

O-Rings.
I like to use Viton O-rings ( Duro 75) since they are cheap, easy to get, have a long shelf life, and are generally what most regulator OEMs use. I replace all of the O-Rings when I service a reg…they are cheap and it just makes sense to do it.

The AS568A series can easily be found at McMaster Carr. McMaster-Carr

The British Standard Extended Series I was able to get from Simply Bearings, they are in the UK but they are used to selling to the US and the shipping is stupid cheap. Buy Viton O Rings Online - Quality O-Rings - Simply Bearings Ltd

820080 "O-Ring" 1EA is an AS568A -006 (Mc Master # 9464K11) and is the balance chamber o-ring
820120 "O-Ring" 1EA is an AS568A -014 (Mc Master # 9464K19) and is the Dust cap O-ring for the Conshelf 1^st stage…if you have that type, not all of them do. It comes with the kit since the kit fits more than one regulator type.
820094 "O-Ring" 1EA is an AS568A -013 (Mc Master # 9464K18) and is the Dust cap O-ring for the Titan 1st stage… if you have that type, not all of them do.
957004 "O-Ring" 1EA is a British Standard Extended Series -611 and is for the HP port. Many people use an AS568A -010 (Mc Master # 9464K15) here and have no issues.
820011 "O-Ring" 3EA is an AS568A -011 (Mc Master # 9464K16) and is for the LP Ports
820038 "O-Ring" 1EA is an AS568A -xxx (Mc Master # 9464K1x) and is for the Removable crown orifice if you have that type, not all of them do.

Some more info will come as I can get it together.

~Chris

Just like Jim, I like this thread.

With the exception of the removable HP orifice oring (only 1 version of Conshelf model has a removable orifice and the early Titans did not have them) and the variance in port orings (different count and size) everything you have posted also applies to the Conshelf and Royal series (not Royal Aquamaster although most of the parts are interchangeable with it as well).

Titan 2nd stage: pretty much all versions of the Titan 2^nd stage fit into this. Also includes the Calypso, Cousteau, Glacia, Standard Octopus, and the LPO and ABS octos. Also a common and easy to work on reg, with easy to source parts. The Primary and Octo are identical except for the color. In the Scuba tools Regulator Savvy manual this reg is beautifully explained as a Dual Adjustment demand valve. This is non-balanced reg but they breathe very well, I like them. The scuba tools inline adjustment tool works very well for setup adjustment in the "slotted" configuration.

This 2nd stage is fairly common and very simple to work on. The OEM rebuild kit is identified as Aqualung part #900010 "Overhaul Kit".


Kit Parts
104134 "Poppet Bearing" 1EA
106738 "LP Seat" 1EA
102510 "Lock Nut"
104913 "Clamp"


Kit O-Rings
820015 "O-Ring" 2EA
957025 "O-Ring" 2EA
820011"O-Ring" 1EA
820010"O-Ring" 3EA


104134 "Poppet Bearing" 1EA
Bad news: So this is one part that there is no easy to find replacement. It seems to be that Aqualung has this made and unless you want to get a batch made up by an injection molder I think you are out of luck sourcing them from a 3^rd party.
Good news: These things almost never go bad. I have replaced some of them when I service a reg but I really only did it because there was one in the kit I was able to obtain. The one I took out was in fine shape and I would have used it again comfortably if I didn’t have a new one handy. I keep the old ones just in case.

106738 "LP Seat" 1EA
You can flip these seats over one time and use the back of the seat just like you did with the front so effectively these have 2 lives. If you have already used both sides and need a replacement then that is not hard to get either. I measured it at .2790” in diameter and .0865” thick. This is the classic and common LP seat. It is "awapable" as a DIY Item with a 9/32" punch from McMaster Carr as Part #3424A22 and is made from 3/32" EPDM sheet available from McMaster Carr as Part # 8990K13 in 2”x36” pieces for only a few $. You could also use the adhesive back version of the same thing if you wanted to, I have seen them come in the OEM kits both ways , but if you use the adhesive back version then you wouldn’t be able to flip the seat.. Follow this link to see some discussion about it. Generic LP seats - Where to buy? Personal note: when you use a punch to do this, be sure that you start with your punch perfectly perpendicular and drive it through while remaining so. Otherwise, you tend to produce sort of parallelogram shaped LP seats that fit funny. Practice…with a single sheet of the EPDM you could literally make hundreds of them.
Vintage double hose sells a similar item here…Shop Online which appears to be the Trident part # AA88 .267” wide and .08 thick. An ok fit but not great.
The Trident part# A149 is a little thicker at .267” wide and .10” thick but still a little smaller diameter than perfect. The Trident part # A119 is larger in diameter at .272” Wide but much thinner at .063” thick.

102510 "Lock Nut"
This is a simple 5-40 Nylock SS nut. It is available from McMaster Carr as part # 90715A006.

104913 "Clamp"
This is your basic zip tie. If you cannot source this yourself then step away from your regulator and call your local SCUBA shop to see when their tech can service your reg for you.

820015 "O-Ring" 2EA is an AS568A -015 (Mc Master # 9464K21) and is for the inlet fitting and the end cap
957025 "O-Ring" 2EA
820011 "O-Ring" 1EA is an AS568A -011 (Mc Master # 9464K16) and is for the 3/8” hose end
820010 "O-Ring" 3EA is an AS568A -010 (Mc Master # 9464K15) and is for the hose swivel, VAS, and the Adj crown

Thanks for taking the time and effort to do this Afishianado! As with the Mares thread, this will be very helpful to a lot of DIY'ers!

Best wishes.

Legend and Titan LX 2nd stage: Also a common and easy to work on reg, with easy to source parts. The Primary and Octo are identical except for the color. The scuba tools inline adjustment tool works very well for setup adjustment in the "slotted" configuration.



This 2nd stage is fairly common and very simple to work on. The OEM rebuild kit is identified as Aqualung part #900012 "Overhaul Kit". What is nice about this regulator is that all of the normally replaced parts in the overhaul kit are O-rings with the exception of one and that is an easy to get part.
I do not have a good photo of the parts kit. Anyone have the kit handy and can scan it in like in the above posts? That would be helpful.
Kit Parts
129176 LP “Seat” 1EA This is the classic and typical molded mushroom type LP seat for balanced 2^nd stages. It is the same as the ScubaPro part #11-250-221 and is also available as the Trident part #A148. I have been able to get local shops to sell them to me and I have seen them listed on eBay.
here is the Aqualung part and the ScubaPro part side by side. SP on left AL on right

Here is the Aqualung part in Black and the Trident part in Blue from several angles




Kit O-Rings
I like to use Viton O-rings ( Duro 75) since they are cheap, easy to get, have a long shelf life, and are generally what most regulator OEMs use. I replace all of the O-Rings when I service a reg…they are cheap and it just makes sense to do it.

The AS568A series can easily be found at McMaster Carr. McMaster-Carr
The British Standard Extended Series I was able to get from Simply Bearings, they are in the UK but they are used to selling to the US and the shipping is stupid cheap. Buy Viton O Rings Online - Quality O-Rings - Simply Bearings Ltd

820015 "O-Ring" 2EA an AS568A -015 (Mc Master # 9464K21)
AP2041 "O-Ring" 2EA is a British Standard Extended Series -606 and is for the shuttle valve stem.
AP1438 "O-Ring" 1 EA is an AS568A -019 (Mc Master # 9464K73)
820011"O-Ring" 2EA is an AS568A -011 (Mc Master # 9464K16)
820010 "O-Ring" 2EA is an AS568A -010 (Mc Master # 9464K15)

Any chance the SEA/Cousteau 1st stage is on the menu?


Edit:

Sorry, please ignore this request. I had the misconception that the SEA used a different diaphragm than the titan/conshelf. My confusion came from the different part #'s used in the aqualung parts lists (103425 vs. 103429) for those two regs. I now realize that 103425 is just the number for the kit that contains 103429 plus a thrust washer. My main motivation for asking about the SEA was finding out what sources for diaphragms are out there, but since it is the same as the conshelf/titan the commonly available trident part will work.

As I recall it is almost identical to the Titan kit, with the exception of the filter. You can compare the OEM part numbers above for the Tital/Conshelf kit to the OEM parts parts for the SEA/Cousteau in this manual on page 16.

Cousteau-SEA 1st Stage Service Manual - Page %CURPAGENUM% of %LASTPAGENUM%