Tuning Tried sealing up your sk19 but it still leaks? This could be the problem

After having the sk19 for a year and a half it developed a leak. I watched the video AOA put that shows where all the usual leaks occur. Didn’t want to dunk it in soapy water so I changed out all the seals mentioned in the video. Despite changing the seals it still leaked.


At this point I dropped my reluctance to put soapy water on my gun and found air leaking from the regulator adjustment knob (above the bottle). I took it apart, took the reg apart but could not figure out where it needed an o ring. At first, I stupidly thought that it needed a seal in the adjustment knob so I tried putting an o ring there. Then tried teflon tape around the threads. Still leaking.

Finally called up AOA to figure it out. Shane was very helpful and quick to tell me to send it in. I didn’t want to send it in. I just wanted some guidance on how to fix it. He asked his tech and all his tech said was it’s an o ring. He said his tech is the type of guy that doesn’t like giving out knowledge. I get it. He doesn’t get paid to help customers fix their own guns. Fair enough. 


One night I wake up at 2 am and can’t go back to sleep. I pull out the sk19 and just stare at it trying to think of a solution. A thought pops up to push down on the piston that connects the reg adjuster to the reg. Disassemble the reg and press down on the piston and voila it’s pops out. Sure enough it had an o ring that was damaged. After swapping it out it now holds air perfectly. 


7B14047D-864D-4800-895A-56093BE2A5E1.1647214129.jpeg




 
  • Like
Reactions: Scotay42
@legionair I’m just getting into reg repairs and I’m not quite sure I understand your explanation of the problem. When you mentioned “the piston that connects the reg adjuster to the reg,” which part are you talking about? I don’t have an LCS rifle so I’m not familiar with the type of reg they use, but I’m interested in learning. Do you have a photo of this piston?
 
@LA- good catch and I thank you for sharing. That AOA video left that area out of that video that talks about o ring replacements.

off topic sort of, but I haven’t shot my LCS since I first bought it back in June of last year. Been too busy with the impact. Tomorrow I’m gonna bust it out and check sight in. I can’t wait till Tuesday when ups delivers the 700cc bottle I ordered for it. That LCS is the perfect platform in need of a larger tank.

While I have it out I’m going to come up with a design on the shoulder pad area to either accept the ST adjustable shoulder butt or just the ST field monopod. 
 
You’re welcome Big Ragu. 


You got me curious about this ST adjustable butt pad. Going to look into it

I’ve been stewing on it for the last week ever since I got my impacts set up with a front tripod support and a rear saber tactical monopod connected to the adjustable butt stock. It’s gonna take some thought as I don’t want to hack one in. 

 
There’s a spring loaded knob(*external adjuster) above the bottle. The knob controls the reg pressure by turning it ccw or cw. When it is turned cw It presses onto the piston showed in the pic. The piston then compressed the Belleville stack to decrease reg pressure. Vice versa for ccw.

Got it. Thanks for the clarification. 
 
Wish my leak was that simple to find and repair. I have a leak somewhere in the back of the rifle blowing air somewhere near the magazine. I took it down as far as i could and replaced every o ring i found in there. Put together and.....leak. SUX !!! Guess i will break down and send it to AoA for repair. Just hope i didn't void my warranty