Results 1 to 19 of 19

Thread: How to repair emag regulator valve pin assembly?

  1. #1

    How to repair emag regulator valve pin assembly?

    For those following this saga, I am now working on the valve. I have replaced all the bad o rings, but I have no idea what I replace on the regulator valve pin assembly.

    http://www.tunamart.com/index.php?c=39&p=115

    Where that white part is, on my gun there are three different discs, seemingly of different materials. They are all gummy and ruined.

    Is there a part I can pick up so I don't have to buy the whole thing? Seems kind of wasteful if I can't throw something on there.

  2. #2
    Join Date
    Jan 2002
    Location
    Halifax, N.S., Canada
    Posts
    8,039
    The two outside ones are urethane orings that come in the oring kit. The middle one is a plastic split washer that separates the orings.
    Except for the Automag in front, its usually the man behind the equipment that counts.

  3. #3
    Do you know what size those o rings are?

  4. #4
    Figure they're 006. I can either use butyl or viton. Going with butyl right now.

    The real question is how I remove that little ring at the back end of the assembly. I need to do that to take the washer off and put the first one on.

    BTW: Thank you athomas. My orings had melted into such a mess that even after messing with orings all day long, I didn't recognize these things as orings! The whole mess looked like some proprietary piece.

  5. #5
    Well, I got them on by squeezing the one over the washer with a pick and a toothpick.

    However, I still have a catastrophic leak from the reg vent hole. I've already replaced the sear piston o ring, and all the o rings on the regulator valve piston assembly.

  6. #6
    Does the leak stop if you back off the velocity? If so, your regulator piston assembly may need replacing.

  7. #7
    Should;ve mentioned: i have backed out the velocity until the o ring is showing. Velocity is definitely at a minimum - at least that's what i think me seeing the o ring is.

  8. #8
    Join Date
    Jan 2002
    Location
    Halifax, N.S., Canada
    Posts
    8,039
    Is the leak out the back of the adjuster or out the side vent hole?

  9. #9
    The vent hole in the regulator portion.

  10. #10
    I thought the side vent hole was a leaky reg seat?

  11. #11
    Join Date
    Jan 2002
    Location
    Halifax, N.S., Canada
    Posts
    8,039
    A leak out the side hole on the back half of the regulator is a leaky oring around the regulator piston.

    A leak out the back is a leaky regulator seat oring.

    A leak out the side of the valve in the front half, is one of the two orings separated by the split washer on the regulator valve pin assembly.

  12. #12
    Well mccarter says they're supposed to be 006. Put 006 viton on there, still have this catastrophic leak.

    At least I figured the plastic washer is split so you can take it off and put the inner o ring on easily.

  13. #13
    Well, I turned the velocity up, that turned it from a catastrophic leak to a very fast leak. So that's improvement.

    Here are some weird things. First, if I turn the air on it seals, there's no leak, then one second later the leak starts.

    Second, the gun holds air after I'm done shooting it and have turned the on/off off. I have to unscrew the tank to vent the air.

    Also, sometimes the on off pin on the gun sticks out even after being degassed, and so I have to take the body off. (ULE body, classic rail, intelliframe).

  14. #14
    Join Date
    Jan 2002
    Location
    Halifax, N.S., Canada
    Posts
    8,039
    Quote Originally Posted by halB View Post
    Well mccarter says they're supposed to be 006. Put 006 viton on there, still have this catastrophic leak.

    At least I figured the plastic washer is split so you can take it off and put the inner o ring on easily.
    I suspect the viton orings are too soft for this location. The have a lower psi rating and a high elongation rating which means they will get distorted easily if they don't have the proper backing. The urethane orings can withstand higher pressures on their own without distorting.

    The valve will hold air after you turn off the ASA. There's no place for it to go. After the last shot, there wouldn't be enough pressure to push the level 10 bolt forward to release the remaining air.

    If the on-off pin sticks out, you can usually get the valve out by holding the trigger in while pulling the valve out the back. This will push the pin far enough into the on-off assembly to clear the body.

  15. #15
    So I have to have polyurethane o rings for this?

  16. #16
    Join Date
    Jan 2002
    Location
    Halifax, N.S., Canada
    Posts
    8,039
    Quote Originally Posted by halB View Post
    So I have to have polyurethane o rings for this?
    Yes.

  17. #17
    I got frustrated. Took everything apart, washed it, scrubbed it all with a paper towel. Rinsed, dried. Put butyl on the valve pin assembly.

    It works. I have no idea why, but it works. At least I think it does, the tank was down to about 600 psi, so I only got a cycle or two out of it. But it doesn't leak air out of the hole!

    Also, there's a problem with the oring sizes on mcarter brown. The reg seat has two different sizes, 008 towards the front, 006 towards the back of the marker.

  18. #18
    Quote Originally Posted by halB View Post
    Also, there's a problem with the oring sizes on mcarter brown. The reg seat has two different sizes, 008 towards the front, 006 towards the back of the marker.
    I know what you mean, it's easy to get confused, but the list is correct. When I posted those, the 006 is listed as a "reg valve pin o-ring" since that's what it seals against on the inside. It's listed as part #779 by AGD, as shown in the ReTro exploded view .pdf on the AGD site. The description is "Four of these desogrin o-rings are used in the Retro Valve, two as part of the regulator valve pin assembly, one on the On/Off pin, and one in the face of the regulator body." The 008 is the actual reg seat o-ring, and seals against the brass reg seat holder.

    Here's the link to the ReTro exploded view: http://www.airgundesignsusa.com/down...oexploded1.pdf

  19. #19
    Join Date
    Jan 2002
    Location
    Halifax, N.S., Canada
    Posts
    8,039
    The orings are probably firmly in place which is why it is working. The act of taking them out, cleaning, and then putting them back washed off any dirt that might have been hindering the seal plus you probably have gotten a better fit this time around. They might keep working for you until you get some urethane orings as long as they don't get stretched and pushed out of position.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •