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Scubapro mark V

Discussion in 'Vintage Equipment Diving' started by racerken, Jan 22, 2009.

  1. John C. Ratliff

    John C. Ratliff Instructor, Scuba

    # of Dives: I'm a Fish!
    Location: Beaverton, Oregon
    2,648
    1,124
    113
    Captain, correct me if I'm wrong, but can't these Mark V seats be reversed if one side is bad? I had thought that was an option. I agree with the statement above about the seat not seeing any wear when not in use, as I've had a Scubapro for many years, and it's doing just fine right now. The seat has not been replaced since the 1980s (if it was then).

    SeaRat
     
  2. couv

    couv Instructor, Scuba

    # of Dives: 1,000 - 2,499
    Location: 13th floor of the Ivory Tower
    4,586
    1,818
    113
    John C….Yes, the old seats (hockey pucks) are flat on both sides. You can flip them and use the other side. One thing I found with any of the seats, you should not take them out of the seat retainer unless you have to. If you must-before you do, index mark the seat and retainer so you can put it back exactly where it came from. I do the same with the piston, but that is probably not necessary.

    Jpope3...Re the hp creep (in addition to what has already been covered) There is a possibility that the reg never got properly cycled and that is all it needs. You could 1) cycle it 20-30 times and see if that solves the problem or 2) Let it sit under pressure overnight and see if that fixes it; the downside to this is if the creep gets too high your second stage will be relieving the pressure all night.

    I'm assuming the o-rings are still ok and that the piston head and stem seals still have lube on them. If either of these is dragging, that could also cause the ip to creep as it slows the piston down before properly seating.

    With a "new in box" regulator like that, you could open it up and change out all the seals in a matter of minutes. The time consuming part of an overhaul is the cleaning. Why not just open that puppy up and replace at least the internal o-rings?

    If you would like to PM me with an email address where you can receive PDF files, I'll send you a diagram with the standard o-ring sizes already printed on it.

    Good luck and keep us posted,

    Couv
     
  3. Jpope3

    Jpope3 Garibaldi

    # of Dives: 200 - 499
    Location: New Jerset, USA
    3
    0
    0
    Thanks, Couv. I'll shoot you a PM in a second. It's possible that this reg was never used at all, in fact, I'm pretty sure it wasn't. (It's been a long time since I closed the business...) I'll try the repeated cycling procedure and, if that doesn't work, I'll leave it under pressure for a while and see how that affects it. Can't hurt, right?

    JP
     
  4. couv

    couv Instructor, Scuba

    # of Dives: 1,000 - 2,499
    Location: 13th floor of the Ivory Tower
    4,586
    1,818
    113
    Hello KittyHawk,

    What is the latest on the turret bolt and hp seat projects?

    Cheers,

    Couv
     
  5. Texfrazer

    Texfrazer Barracuda

    # of Dives: 500 - 999
    Location: Knoxville, TN
    349
    13
    18
    Hi KittyHawk,

    Like Couv, I would also be interested in knowing how things are going with the bolt and seat.

    All the best!

    Tex
     
  6. AfterDark

    AfterDark Solo Diver

    # of Dives: 500 - 999
    Location: Rhode Island, USA
    7,913
    3,385
    113
    This is my kinda thread! I got my MKV brand new in 1968 for the ungodly sum of $95.00!
    Big bucks to a yard racking, lawn cutting, snow shoveling, bottle collecting, 14 year old in 1968! I consider it among the 5 best purchases I've ever made and the only regulator I've ever owned. I've had it retro fitted down through the years with various features I liked. The only thing that didn't work out was the balanced 2nd stage. Darn thing would free flow after a few dives, after 2 years I told the shop to remove it. I never found that much of a difference anyway. Someone mentioned the 1st isn't good for ice diving, not true with the enviro pack I used it year round here in New England without any issues, truly the timex of regulators. Later this AM I'm going to pick it up at the shop as I had it overhauled after sitting in it's bag for 15 years. I fully expect to finish up however many diving years I have left diving with the MKV. My diving rebirth starts tomorrow!:D:cool2:
     
  7. couv

    couv Instructor, Scuba

    # of Dives: 1,000 - 2,499
    Location: 13th floor of the Ivory Tower
    4,586
    1,818
    113
    Hello AfterDark,

    Good for you! That reg will continue to server you well. I do not know what to say about the free flowing second stage as there are a number of things that could cause the problem. One thing you must always start with when tuning a second stage is a steady intermediate pressure (IP) from the first stage. See this thread for some helpful pointers. http://www.scubaboard.com/forums/regulators/260452-regulator-checklist-inspection.html

    Cheers,

    Couv
     
  8. redacted

    redacted Guest

    Uncontrollable freeflows are not a characteristic of the Scubapro balanced 2nd stages. Your shop should have been able to fix the problem or replace the regulator is defective. But you are right, for most recreational diving, the difference between the balanced and the unbalanced barrel poppet design may be hard to notice, but it does show up when you measure cracking pressure.
     
  9. AfterDark

    AfterDark Solo Diver

    # of Dives: 500 - 999
    Location: Rhode Island, USA
    7,913
    3,385
    113
    Thanks for the link Couv. The shop didn't know what to make of the free flowing either. That's why it went on for 2 years, they kept trying to fix it without success. I had lots of faith in that shop as they have been Sucbapro dealers since the 1960's nd taught me to dive. This was the only thing they couldn't help me with. They offered to send it to the factory but since I never perceived a difference and I wanted to dive not wait for a regulator I told them to dump the mod.
    Awap, the reg wasn't and still isn't defective. Maybe the factory could have fixed it. My vision was of having to send it back to the factory over and over again and be without it for long periods if they couldn't. Having experienced a real defective regulator at 70' (no air delivery) requiring a free ascent I choose to stick with the original configured second staged so I could continue diving. I dove for years after having it changed back with zero problems, I don't regret it nor miss the balanced 2nd in anyway. I dive therefore I am happy. Thanks for your reply.
    Edit: Forgot to mention that I picked it up yesterday after a overhaul and will be using today. Sure does breathe nice on the surface. I'll let ya'll know later how it works under the sea.
     
  10. redacted

    redacted Guest

    We have not established the specific regulator model but I think you must be dealing with a 109 (Adjustable) and having it converted to a 156 (Balanced Adjustable). The difference between the 2 is about $10 worth of fairly straight forward parts (poppet w/seat, spring, and spring pad/balance chamber). If it is working fine as a 109 then the orifice and body of the regulator must be OK. I would have to wonder why the tech could not work this out - it's not rocket science. It is simpler than fixing a leaking faucet.
     

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