Impact M3 bottle suddenly very hard to screw/unscrew after routine air emptying to lower 2nd reg

[TheDaleness]

I've had an Impact M3 that has been working without issue for the past 6 months. But today something went wrong. I bled the system of air as I normally do whenever I want to decrease the reg pressure: unscrew the bottle, then slightly turn the 2nd reg adjuster counter clockwise until the air begins to empty. When the system was empty, I turned the 2nd reg screw clockwise to lower the pressure.

But then, when I screwed the bottle on, as soon as the seal engaged and the gun filled with air the bottle instantly became too tight to screw/unscrew. If I put on a pair of really grippy work gloves, use two hands, and twist as hard as i can, then I can get it to turn in either direction, but I don't want to do anything until I know what might be going on. I'm guessing something happened with an o-ring in the bottle valve or regulator, allowing some air to pass through, so I'm fighting a lot of pressure to screw/unscrew

Any ideas what could be causing this? And what to do from here?

Thanks guys.

 

[MikeVV]

Have you...ever lubed the o-ring or threads ?
A little silicone grease...goes a long way toward making threads live and rubber seals live a nice long life.

Mike

 

[TheDaleness]

Hi Mike, yes, I've kept the threads well lubed with silicone grease and the o-rings with silicone oil.

 

[FX-USA]

Hi Daleness,

We’ve forwarded this to our tech department if you’re still having difficulties please contact us via email or phone. Next week.

Regards,
FX Airguns USA

 

[TheDaleness]

Hi FX-USA, thank you for responding here so quickly. I actually just sent an email to <[email protected]> right before posting here. I wasn't expecting to hear back till Monday, so I thought I'd ask the forum in case maybe I could find a fix and still go on the hunt I had planned this weekend.

 

[rc4fun]

Oh No! Silicone is the wrong lube to use on those threads, it can cause galling. Clean it with alcohol or acetone and then use a PTFE or Molly lube. Silicone is not a metal to metal lube.
The high pressure in the tank makes it difficult to remove or install once the valve is opened. If you wait (shoot) until the bottom end of the fill (150bar) it will be quite a bit easier.
Do put a bit of silicone on the o-ring, dosen't need much.

 

[Airgunmann]

Why are people removing the bottle so much to adjust the rear reg amp reg can be adjusted up or down with air in the gun I understand you have to to get at the front reg the rear reg adjust a little at a time and dry fire if there is air in the gun

 

[TheDaleness]

Oh No! Silicone is the wrong lube to use on those threads, it can cause galling. Clean it with alcohol or acetone and then use a PTFE or Molly lube. Silicone is not a metal to metal lube.
The high pressure in the tank makes it difficult to remove or install once the valve is opened. If you wait (shoot) until the bottom end of the fill (150bar) it will be quite a bit easier.
Do put a bit of silicone on the o-ring, dosen't need much.

Wow! Thank you rc4fun! This is really good to know. Cleaning it off now. Could you recommend a specific brand of either of the lubes you mentioned? Is there one that is BEST for metal on metal?
I have Tri-flow Clear Synthetic Grease that says, "Formulated with PTFE. For Use on packed bearings, cable assemblies, gaskets and o-rings."

 

[TheDaleness]

Why are people removing the bottle so much to adjust the rear reg amp reg can be adjusted up or down with air in the gun I understand you have to to get at the front reg the rear reg adjust a little at a time and dry fire if there is air in the gun

If this is a safe way to lower the rear reg, without damaging it, that would be great! That would save a lot of air and hassle.
So you're saying turn the rear reg screw around 1/16th-1/8th of a turn, dry fire, and repeat until the you reach the desired pressure.

I've only ever come across posts, videos, manuals, product descriptions, etc. of people saying "NEVER turn the reg screw clockwise under pressure! You will damage the reg!"

I'm confused.

Anyone else endorse this method?

 

[Airgunmann]

I've read about a 1/4 turn up or down and dry fire a couple times see where it settles out and adjust accordingly

 

[rc4fun]

I have Tri-flow Clear Synthetic Grease that says, "Formulated with PTFE. For Use on packed bearings, cable assemblies, gaskets and o-rings."

Yes the tri flow will be ok.
This works also Long-Life Grease + MOS2 100g MPN: 2003 https://a.co/d/92MrkAB

 

[TheDaleness]

Yes the tri flow will be ok.
This works also Long-Life Grease + MOS2 100g MPN: 2003 https://a.co/d/92MrkAB

That was it! The silicone grease! I fired the rifle down to a low enough pressure that I could unscrew the bottle. I cleaned all the silicone grease off the threads with acetone, a toothbrush, and a microfiber cloth. I then applied a molybdenum film lubricant and then put Tri-Flow grease on top of that. Now it screws on/off easier than it ever has. And the gun is working as it was before.
A lesson in materials/lubricants/mechanics. It was dumb to not look into if silicone grease/oil was an appropriate lubricant for metal-on-metal before applying it.
Thanks rc4fun!

 

[GA_LeadHead]

Thanks for this threadd, I used silicone grease on the threads of my bottles and I'm having the same issue.

 

[671mdc]

Thanks for the thread

 

[GA_LeadHead]

I cleaned my threads with denatured alcohol and then applied a little Molly grease and the issue has gone away.

 

[qball]

Metal to metal contact definitely use your normal lithium bated grease you use on cars, or basic anti seize would work too. Keep in mind to keep the orings away from it. Silicon grease is for orings/plastic parts ONLY.

Yes, you can turn the reg adjustment screw 1/8 of a turn at a time then dry fire couple of times then repeats to reduce reg pressure.

 

[Trucker3573]

Yeah silicone on metal to metal contact is the worst. I found out the hard way as well shooting trap. I put some on the action of my over under shotgun and by about the 15-20th shot I could hardly open or close it.