Piston shaft oring Viton Duro 90 for Mk10

[Slamfire]

The -010 oring size is used in several places:

• LP hose inlets
• LP plugs
• LP hose outlets (G250)
• G250 orifice
• Piston shaft oring (Mk10)

All of these are nominally a duro 70 with the exception of the piston shaft oring which is specified as a duro 90. Do you guys think I could get by with buying a single batch of viton duro 90 for all these uses?

I've read around here that viton has a long shelf life. What is the shelf life of viton?

More specs about the batch here: McMaster-Carr

 

[redacted]

If it seals OK, use it. It may be a bit of work getting duro 90s onto things like the orifice, but it should be doable.

Another alternative is to collaborate with some other DIYers. 100 each of any o-ring will last a DIYer a long time. Viton shelf life can go 20 years according to Parker Seals.

 

[Couv]

The only place where I had a problem using a duro 90 -010 was on an adjustable orifice. Fitting it on the orifice was just a little difficult, but the real problem was pushing it down the barrel and screwing it in. I know I nicked a couple before I had any success. Getting the orifice back out was more of a problem too.

 

[redacted]

The only place where I had a problem using a duro 90 -010 was on an adjustable orifice.

The metal orifice really wants a 902 rather than a 010 and the higher duro could make a difficult squeeze impossible.

 

[Slamfire]

Well I guess I'll find out soon enough. Right now there is a 20 year supply of orings coming up my way. It is still about 1/5th the cost of a new G250 annual service kit. I'll post my tribulations with the orifice when I get the orings and try them out. I don't think it'll be any harder than the time when I broke a poppet trying to get oversized non-metric orings into the balance chamber.

 

[Slamfire]

I just came back from a test dive for the viton duro 90 orings on a G250. It worked great. Everything sealed and worked perfectly fine. The reg was breathing great all the way to 125'. I replaced a -011 on the external adjustment knob and a -010 on the orifice. Getting the -010 in the orifice was difficult. I did nick one oring, but hey, there were 99 left over. Getting the orifice in the barrel did present more than the usual resistance but it went in nonetheless. I have not tried to take the orifice out again since.

I am still waiting for a couple of new hp seats to arrive and then I'll try the -017 and -010 on the piston. Right now my Mk10's are using recycled HP seats that still lock up good with no creep right after the service I gave them a few weeks ago. I want to see how the trident HP seats work out.

BTW if anybody wants a few -010, -011, or -017 viton duro 90 orings, pm me and I'll put some in an envelope and send it over snail mail.

 

[redacted]

I just came back from a test dive for the viton duro 90 orings on a G250. It worked great. Everything sealed and worked perfectly fine. The reg was breathing great all the way to 125'. I replaced a -011 on the external adjustment knob and a -010 on the orifice. Getting the -010 in the orifice was difficult. I did nick one oring, but hey, there were 99 left over. Getting the orifice in the barrel did present more than the usual resistance but it went in nonetheless. I have not tried to take the orifice out again since. .

My limited experience is that out is a bit more difficult than in when it is tight. Once you are sure the threads are disengaged, you will need to push fairly hard on the orifice knife edge. When it is not too tight, an eraser seems to work well. If it is tight, the eraser just tends to get cut up so you may have to use something harder. A new metal orifice will eat most of a $20.

 

[Slamfire]

Before putting in the new duro 90 oring, I tried getting the orifice out with a pencil eraser and as you mentioned, it was getting cut up. So I flipped the wooden pencil around and pushed it out with the conical wood section. I reasoned that the conical section of the pencil would avoid engaging the knife edge directly perpendicular and reduce likelihood of damage. And besides pencil wood is softer than brass.

After taking the orifice out I closely inspect it for knicks or burrs and finally softly rotate the knife edge on the tip of my tongue to see if I can feel anything rough.

We'll see how it goes when I get to take that duro 90 out.

 

[Zung]

I use a chopstick to push the orifice out and it works fine, but the 2-010EP70 is a bit tight, so I ordered some 902EP70 from The Oring Store. They're good for small quantities.

If I had to do this again, I think I'd go for a full bag of a 100 each 010EP70, 902EP70 and 010VT90 from mcmaster. The quantity appears to be outrageous, but the price is more or less the same. At least the 010EP70: they go really fast with all the old junk I get from the 'Bay.

 

[axxel57]

Don't forget to put liquid silicone from both sides into the valve body when removing the orifice. First turn it 1/2 to one turn inwards and then start to turn the orifice outwards. The lubrication makes also quite some difference in pushing it out of the valve body.