just got this...
Scubapro Mark 20. In our last email we reported that the first stage of a Scubapro Mark 20 regulator used by a diver with the National Oceanographic Atmospheric Administration developed a serious open crack. Scubapro told NOAA that the problem was due to overtorqueing the yoke nut and we reported that NOAA accepted that explanation. We were wrong and NOAA disagrees with Scubapro. NOAA contacted us and Dave Dinsmore, director of the NOAA diving program, said, "Both Scubapro and NOAA hired independent experts to evaluate the cracks and assess the likely cause. NOAA's expert determined that no deformation, thread damage or gouging was noticed at the yoke thread (male) and yoke adapter (female) indicating that the yoke had not been overtorqued." NOAA discovered cracks in three out of 298 regulators. NOAA ordered the MK20 out of the water and Scubapro has since replaced all of NOAA's MK20 regulators with MK25 models. If you own a MK 20, carefully examine the second stage for cracks and if you find one, contact your Scubapro dealer.

Freddie
This does not look like what you were describing, but does concern the Scubapro Mark 20 and it is really startling. It would surely get your undivided attention.
Mickey
http://www.ndc.noaa.gov/pdfs/sb05-01.pdf

Freddie and Mickey,
I own a scubapro MK 20 ....
you have my full attention.

Mare

Examine for cracks? To heck with that, I want a new reg!
Scubapro's website does not mention this problem, though they do mention a problem using the non-scubapro BCD conversion kit for the Air2.
I have written to Scubapro, as well as my local dive shop where I bought our gear.

sounds like a total recall is needed...Lets make some major waves here !!

If I don't get a reasonable response from the dive shop and/or Scubapro by next week, I will start a new thread for folks with this regulator. Maybe we can get together and voice our concern in concert if needed.

I beat you to the punch Freddie! I just purchased a new first and second stage...I will be checking my old ScubaPro regs tonight....thanks again for the Cressi BCD recall warning....I got it back last month

My tech's response to all this:

Hi Seb,
The NOAA tech was over-tightening the yoke nut and caused the problem. It took 8 years of picking up the scuba unit by the reg (which you shouldn't do with any system) to cause the failure. In essence, a technician caused failure. Don't sweat it.

I also e-mailed SCUBAPRO, I'll post their response.

I also received the e-mail Freddie posted (came from Ben Davison at Undercurrent). This was in reality the second e-mail in a few days from Undercurrent dealing with the Mk-20 failure at NOAA, except this one specifically stated the problem was NOT due to overtightening the yoke nut. It is possible Seb's "tech" may have incorrect (or incomplete) info. Also I have not seen anything written regarding "8 years of picking up the scuba unit by the reg to cause the failure". Wonder where that came from.

As someone whose wife has to remove her BC and tank in the water and have it lifted out of the water by the divemaster/captain on the boat, I have often seen them grabbing the BC/tank by the regulator. Probably quite a common occurrence. I have also seen them grab the regulator and lift when they help people climb out of the water using the ladders.

As an engineer who has been involved in several evaluations of failures in high pressure equipment, it is usually best to wait until the real experts (i.e., metallurgists and structural engineers) have a chance to evaluate the failed parts with proper instruments and techniques. They can usually tell whether the failure has been caused by metal fatigue, impact, over-tightening, etc. Regardless, I would encourage ScubaPro to quickly, and without bias, evaluate the failure and take corrective action, even if it means a total recall program and replacements. The potential loss of business from bad publicity and/or misinformation is probably too great to not do what is necessary.

BTW, my wife also has a Mk-20. I will be talking to our local dive shop this weekend.

Good points Doc.

One thing I hate, is other people moving my gear...I caught a divemaster in Cozumel carrying my BC (with tank) to the boat by the reg HOSES (1st and 2nd)...My new BC has a handle on the back for exactly that reason...

Hi all I received this today about the MK20

Dear Authorized SCUBAPRO UWATEC Dealer,
Please note the attached correspondence. The first letter is communication to you,
our dealer and the second is information we will be giving out to consumers as
they call in regarding the MK 20 First Stage Regulator.
© 2005 by Johnson Outdoors Inc.

MK20 Yoke / DIN Service Bulletin


--------------------------------------------------------------------------------

Dear Authorized SCUBAPRO UWATEC Dealer,

This is a communication to you, our dealers, to inform you we are in the preliminary stages of an upgrade program for the MK20 first stage regulators.

Recently, we were notified that a diver had reported a crack in and around the body of a MK20 first stage regulator where the yoke retainer seats against the internal body of the regulator. We immediately conducted an internal review utilizing our SCUBAPRO ® Engineering Team. Simultaneously, we asked the independent experts at Exponent Failure Analysis Associates to determine the root cause. Exponent is a leading failure analysis consultancy with technical expertise spanning a wide range of scientific and engineering disciplines.

Exponent has completed an extensive and comprehensive independent review and analysis of the MK20 design and materials, as well as detailed inspection and analysis of both the failed unit and properly working MK20s. They determined the crack occurred due to a combination over torque and exposure to an underwater environment. The crack may be initiated if exposed to over torquing and over time, a larger crack may develop when exposed to harsh environmental conditions and, in a small number of cases cause a failure.

As a result of these findings, SCUBAPRO’s engineering staff and Exponent both recommend that all MK20s be updated with Universal Yoke Retainer (PN 10.103.115). This retainer transfers the mechanical load to the yoke retainer and not the body. The upgrade to this Universal Yoke Retainer and proper torque settings have been found to eliminate the stress placed on the body of the regulator at the location of observed cracking. This update, available in both Yoke and DIN, will soon be available to you to so that you may update your customer’s MK20 first stages. We will be mailing each Authorized Dealer more correspondence on this program within the next week.

In closing, we work hard to earn the trust of you and your customers every day, and know that our reputation is based on what we do, not what we say we will do. That is why when we first learned of a problem, even though it involved a product no longer produced or sold, we took responsibility and immediate action. At SCUBAPRO diver safety comes first.

Please feel free to contact your Sales Representative or our Technical Services Department if you have any further questions.

SCUBAPRO UWATEC
North America

© 2005 by Johnson Outdoors Inc.

SCUBAPRO MK20 First Stage Communication


--------------------------------------------------------------------------------

Thank you for contacting us regarding the SCUBAPRO MK20 First Stage Regulator. We certainly appreciate the opportunity to provide additional information and clarification on this matter.

Since 1996, tens of thousands of MK20 first stage regulators have been used by divers under rigorous conditions in both warm and cold water. When we first learned that a diver had reported a crack in and around the yoke thread area of a MK20, we immediately conducted an internal review utilizing our SCUBAPRO® Engineering Team. Simultaneously we asked the independent experts at Exponent Failure Analysis Associates to determine the root cause. Exponent is a leading failure analysis consultancy with technical expertise spanning a wide range of scientific and engineering disciplines.

Exponent has completed an extensive and comprehensive independent review and analysis of the MK20 design and materials, as well as detailed inspection and analysis of both the failed unit and properly working MK20s. They determined the crack occurred due to a combination over torque and exposure to an underwater environment. The crack may be initiated if exposed to over torquing and over time, a larger crack may develop when exposed to harsh environmental conditions and, in a small number of cases cause a failure.

As a result of these findings, SCUBAPRO recommends that all MK20s be updated with Universal Yoke Retainer (part number 10.103.115). This retainer transfers the mechanical load to the yoke retainer and not the body. This Universal Yoke Retainer and proper torque settings have been found to eliminate the stress placed on the body of the regulator at the location of observed cracking. This retainer will soon be available, free of charge, at an Authorized SCUBAPRO Dealer. A Dealer can be located via our website www.scubapro.com or by calling 619-402-1023.

In closing, we work hard to earn the trust of our customers every day, and know that our reputation is based on what we do, not what we say we will do. That is why when we first learned of a problem, even though it involved a product no longer produced or sold, we took responsibility and immediate action. At SCUBAPRO diver safety comes first.

Please feel free to contact your local Authorized SCUBAPRO UWATEC Dealer or SCUBAPRO UWATEC if you have any further questions.

SCUBAPRO UWATEC
North America

I am happy to see that ScubaPro has taken positive action regarding the Mk-20, both in using an independent outside organization to evaluate/identify the cause and in offering corrective action.

As part of my professional life, I have used and interacted with personnel from Exponent Failure Analysis Associates and found them to be very thorough and very proficient. It speaks well of ScubaPro's actions.

We have 3 of these 1st stages. I've always been impressed with Scubapro's service and upgrade programs and would expect nothing less from them.