Reassembling my SP MK2

[lhpdiver]

Well the good news is... soaking does work. This second stage has been sitting in straight Simple Green for about 3 weeks now and is finally disassembled. The bad news is that I tried wedging a screwdriver against the "housing" and snapped the "stem". And what makes matters worse, that didn't help at all. It was only when I said to myself, screw it break the "case", that the "valve body" came apart (and of course I didn't break the case after all).

 

[redacted]

Well the good news is... soaking does work. This second stage has been sitting in straight Simple Green for about 3 weeks now and is finally disassembled. The bad news is that I tried wedging a screwdriver against the "housing" and snapped the "stem". And what makes matters worse, that didn't help at all. It was only when I said to myself, screw it break the "case", that the "valve body" came apart (and of course I didn't break the case after all).[/QUOTE

Bummer. When I screwed mine up, it was the housing that broke. A picture of the broken housing is in my profile. You can see the underlying brass barrel and the plastic pieces that had covered it. I reassembled it, one piece at a time, with JB weld. It seems to be working OK. There are at least three versions of that housing and all look quite different so I'm not sure the brass barrel is still in the current version (mine is 1994 vintage).

I'm surprised the stem snapped. I guess you must have slipped and sheared it. As I look at the scematic, it looks like we could have done more disassembley before trying to unscrew the body from the housing. If you remove the lock nut and all the pieces that frees up from the top of the housing, and the orifice from the metal body, everythig should come out except mayme the plastic poppet. Them we probably could have fashioned a screwdiver like tool to engage the grove in the top of the housing where the lever sat. That should stabilize the housing as you turn the nut on the body and relieve stress between the case and the housing where mine faliled. At least we can learn from our mistakes.

YGPM

 

[jumbo]

I am not going to kick a dead horse too long, so here are a few tips not mentioned previously.

Put crystolube on any parts that have metal to metal contact and dynamic o rings, or if they move against metal.

To avoid the vise action which I advise, get a wrench from one of the scuba tool websites that allows your to screw a star wrench into one of the low pressure or high pressure ports this allows you to get a ton of toque without damaging the housing.

Beyond that pick up a scubapro universal tool, it is really handy and will allow you to easily work on most of the scubpro regs, I always keep one in my save a dive kit.

JUMBO

 

[lhpdiver]

I'm surprised the stem snapped. I guess you must have slipped and sheared it. As I look at the scematic, it looks like we could have done more disassembley before trying to unscrew the body from the housing. If you remove the lock nut and all the pieces that frees up from the top of the housing, and the orifice from the metal body, everythig should come out except mayme the plastic poppet. Them we probably could have fashioned a screwdiver like tool to engage the grove in the top of the housing where the lever sat. That should stabilize the housing as you turn the nut on the body and relieve stress between the case and the housing where mine faliled. At least we can learn from our mistakes.

Actually, I had removed the hex nut, lever etc. Guess that left the stem an easy target.

I had dreams about that screwdirver like tool. I envisoned it being made of hard rubber. With all the things at ScubaTools I'm surprised they don't have a tool.

Next question... What can I use to unscrew the orifice ? Is it a simple allen wrench ? I just picked up $10 worth from Lowe's and I can't get a good fit.

 

[lhpdiver]

I am not going to kick a dead horse too long, so here are a few tips not mentioned previously.

Put crystolube on any parts that have metal to metal contact and dynamic o rings, or if they move against metal.

To avoid the vise action which I advise, get a wrench from one of the scuba tool websites that allows your to screw a star wrench into one of the low pressure or high pressure ports this allows you to get a ton of toque without damaging the housing.

Beyond that pick up a scubapro universal tool, it is really handy and will allow you to easily work on most of the scubpro regs, I always keep one in my save a dive kit.

JUMBO

A first stage handle is on my shopping list. I had picked up a "Multi-Tool" from ScubaTools but I guess I need a Universal tool as well for some things.

Thanks

 

[redacted]

Next question... What can I use to unscrew the orifice ? Is it a simple allen wrench ? I just picked up $10 worth from Lowe's and I can't get a good fit.

I've always used a short, wide, flat tip screwdriver. But be careful it does not slip. If it does it will eat up the slots and could damage the metal o-ring seating surface. So far I have only eaten up 1 of the plastic orifices (needed to soak it more). I believe the metal orifice (??-109-109) and ther plastic orifice (??-500-109) are interchangable if you can find them. A screwed up plastic orifice can still be worked with a good phillips tip screwdriver without risk of damaging the metal body so it can still be removed. I'm going to play around with modifying a std screwdriver to prevent the slipping that can occur

 

[lhpdiver]

When I use my "inline adjusting tool" I can unscrew the orifice quite a bit but it is still sunk in about 3/8". Do I need to unscrew it ALL the way out or at some point do I need to give a good tug (or shove from the other side) ?

 

[redacted]

When I use my "inline adjusting tool" I can unscrew the orifice quite a bit but it is still sunk in about 3/8". Do I need to unscrew it ALL the way out or at some point do I need to give a good tug (or shove from the other side) ?

Easiest to just remove the demand valve body and push it out with something soft like an eraser. The threading is all below the o-ring seating surface so it will not unscrew any further than that. You have to push it out from the other side or risk damaging the knife edge.