Scubapro O-ring Sizes

[Zung]

This MK20 I've just got off the 'Bay, so I replaced eveything out of general principle.

Interestingly, it's like new, no scratch, but with a lot of slow creep. Inside, the seat is barely marked, but the lube has become very thick, with some white goo, like dried-up thickener from the grease. I replaced all the soft parts, and also the original SS piston because I have a composite one on hand, and every other MK20 in my corral has it.

After the treatment, it's snappy as it should. Too bad I replaced the piston, so it's not exactly a before/after sort of comparison.

 

[Couv]

Thumbnail looks like a game of "Hangman"

 

[Zung]

I just exchanged emails with theoringstore.com about 90 duro viton orings. They're adding them to the website this weekend! Best part is that shipping is a flat $3. I'm going to give the viton orings a shot.

I just placed an order of 010V90 plus some others (anyone seen my bag full of 016's? ), and there're a few caveats:

• The Viton 90 are listed on their new .net Web site: The O-ring Store, Online O-rings and O-ring Kits. The old .com site doesn't list them
• The lead time is 1-2 weeks
• The price break starting at 25 pcs is gone
• Shipping has gone up too: $7 instead of $5 to Switzerland

But it's still worth a try.

 

[raftingtigger]

I have a original (bought new on 9-3-71 SN# 171195) Scubapro Mark 7 regulator (1st and 2nd). I'm getting a small air leak eminating from the ambient water port. Per the troubleshooting guide this is from a leaking piston o-ring. Since I now have an extra 1st stage, I'm servicing this one myself. I have the original "Technical Manual for Scubapro Regulators" that came with the regulator. This includes exploded diagrams and part numbers for Mark I - Mark VII 1st stages and "conventional downstream valve second stage". Very useful BUT Scubapro seems to have changed the part numbers in the last 39 years.

I understand the 2 needed o-rings are the same as used on both the Mark 5 and Mark 10. Does anybody know what sizes they are IN ENGLISH (ie. ID and material diameter in either English or Metric measurements).

The smaller o-ring is Cat. No. 101-6 (one that is harder to remove) and the larger one is Cat No. 101-3* in my manual

I have bought the assembly and 'bullet' from ScubaTools.

 

[redacted]

Scubapro part numbers and English are not in the same book. The o-rings I use for the HP piston o-ring is a 2-010, duro 90 in viton (EPDM, Urathane, or Nitrile would also work): and a 2-022, Duro 70 (or higher) also in Viton (but those other materials will also work.

But chances are other o-ring may be reaching the end of their useful life also. Link is a reasonably current schematic of your reg: http://www.scubaproregulatormuseum.org/MK_7_LATE_MODEL.JPG

 

[Couv]

I attached a file in this thread that has the o-ring sizes annotated on the diagram.

http://www.scubaboard.com/forums/regulators/366221-light-yoke-vs-heavy-yoke.html#post5676128

 

[ECpirates96]

Looking for the cross size for Scubapro# 1050428 which is #7 on an MK17 diagram. Also does the Trident Filter come with a retainer on a yoke regulator or do you use the old one. I am just building some kits for my regs and am a little worried about some parts like the getting HP valve. Thanks

 

[Zung]

Item #7 is a standard DIN o-ring and should be 2-111 PU Duro 85, but EP or VT should work: it's only a static face seal.

I don't think the Trident filter comes with a retainer; actually I don't even think it fits, but I may be wrong. The old retainer can be re-used if it's still in good shape.

 

[redacted]

MILLERJE asked for it, so here's the D400, but I have no data on the square-ring, 11-014-212.
Anyone cares to proof?

I don't know if anyone ever answered the question about the switch o-ring. I have an older schematic (12/97) that pictures a round o-ring p/n 01.050.211. I did replace that seal (once) with a round o-ring and it was quite a job but works fine. I believe I used a 2-116 but can't find a record. That looks to be in the right range since the SP p/n 01.050.217 (Mk10 cap) is a 2-117. There is a pattern to most of the SP numbers that at least gets you in a ballpark.

 

[V&G]

Is it possible to use Buna-N o-rings instead of EPDMs in tank valve?