Scubapro 109, frozen balance knob

[MacGyver - DXS]

I am new to this, but I have a long experienced diver working with me.
I just bought my first reg set off ebay,
[sp mk5 1st /109-108 2nd stages], for $85. Based on my limited experience, that seemed an excellent deal.

However, now that we have them in hand, it is obvious that the former owner, [who was somwhere in california], was not big on maintaining his gear. The first stage looks ok, but both second stages have corrosion problems. This would not be a major issue, save for the fact that the 109's balance knob is frozen in place, making disassembly impossible.

Has anyone else had this problem?
How can this be approached, so as not to damage the reg?
I realize this may be a lost cause, but I want to try everything I can.

Thanks in advance.

 

[Couv]

It's a common problem-partly a design issue as there is nothing to keep water/salt out of the threaded area. However, don't lose hope. Sometimes, all it takes is a sharp blow to the end of the knob to break the corrosion loose. Not too hard-it's soft metal. If no joy, a long (over night) soak in hot soapy water followed by gentle persuasion with a pair of pliers (protect the chrome knob with a rag, piece of plastic, or an old belt.) Gently torque the knob clockwise then counter clockwise keeping in mind the part is made of brass. If no help try a hot and cold treatment. Place the regs in a bucket of ice water then into a bucket of boiling water. Do this a few times and try again. If none of this works (or even if it does) get back with us and we'll continue with a few more radical solutions like vinegar or ultrasonic cleaning etc.

BTW Welcome to the Dark Side.

 

[Seaross]

my first 109 adjustment knob was frozen like that, lot of pentrating oil i think all the parts for resoration are available from vintage double hose, I bent the adjustment knob but eventually removed, heating is an idea but melting oring and poppet and discouloration might be an issue but its the corrosion that would worry me, its an excellent set up just take it to the local dive store for a full service(probably run you a couple hundred bucks depending on poppet selection and degree of corrosion)you will have piece of mind that your rig is in top notch shape, then later once you are a little more familiar with diving and function of regulator watch all the associated youtube videos and talk to other divers to really appreciate the gem you have and the years of service you will get for very little in investment. If you do take an uneducated look at it, the spg spool, exhaust port and poppet and derlin orifice will probably need to be replaced as well as all the orings, the set screws in the retainer ring are probably seized as well(make sure you have exactly the right sized screwdriver or allen key.(while removing the poppets use a pen or something other than a screwdriver as not to scratch the inside of the poppet chamber the diaphrams get a little deteriorated but for the most part you can buy pretty much anything parts wise to repair, I have read it all around SB and agree your few hundred dollar investment will run just as good as a new reg, even if the exerienced diver is helping you i still would recommend your first service by a dive store familiar with these regs, as you become a more experienced diver you will realize problems like freeflow or microbubbles(from joints or hose) or strong breathing effort and know how to adjust and fix them yourself. and after all that you will start thinking maybe a double hose would look pretty good as your next regulator,

sometimes the old things arent junk
just misunderstood.

 

[AFdivedoc]

I've had a couple of fleabay 109's in that condition. Follow Couv's advice above. Take your time and apply gentle force after soaking--it'll break free. They will likely clean up well, and you'll be rewarded with a couple of great performing second stages that look great and have decades more life in them.

Remember this problem as you maintain your regs. I take the adjustment screw out after every salt water dive trip (I dive mostly fresh water otherwise), clean it, dry it, and lube it.

 

[MacGyver - DXS]

Alright. Got the 109 apart!
The guy who had this rig must have failed to rinse it completely.
Using the vinegar solution recommended by VDH, I cleaned both 2nd's, removing a good deal of corrosion. Only one surprise; someone converted the 109 to a 156. So, I have ordered the correct kit. I've reassembled the 108, albeit with one problem. The exhaust tee is cracked such that it is unusable, and since it's the pre HP version, the repro's from VDH don't fit. Does anyone know where I can get a tee that will fit?

 

[James79]

I have a 108 with the same issue... I 3d printed a bushing to adapt it to vdh/universal 109 exhaust T's. I can whip up another in a couple days if you need.
v/r
James

 

[Seaross]

turn the tee on a 90 put your finger inside the rubber tee and pull the vdh repro's are tight but you can get them on the more oval exhaust housings its just a battle, once mounted turn it straight from its rotated position

 

[James79]

turn the tee on a 90 put your finger inside the rubber tee and pull the vdh repro's are tight but you can get them on the more oval exhaust housings its just a battle, use mounted turn it straight from its rotated position

Op is referring to the old style 108 exhaust that the vdh and any other 109 tee is too loose on. I have my improved adapter designed, but am out of town for a week. I'll print it when I get back and post pictures then.

 

[MacGyver - DXS]

I have a 108 with the same issue... I 3d printed a bushing to adapt it to vdh/universal 109 exhaust T's. I can whip up another in a couple days if you need.
v/r
James

That would be fantastic! Let me know what I owe you.

 

[James79]

I'll be home monday and print/test the new one... once I have right I'll let you know