It's the Pneumatics, Dummy!

[Yellow5]

So rebuilding the Nasty springfed Typhoon that's been kicking around the basement forever..found shredded o-rings at the valve & between the 2 coupler pieces in the lower body tube. I'm thinking, cool, I know what's wrong now! Replaced those, the back half of the gun (all the 'Sheridan' parts) holds air, but then the o-ring in the LPR melted. Like, I had to wipe it off the plunger rather than pick it out. It had a square profile pre-disintegration. Anybody know what size/designation it is for ordering purposes?

I'm talking about the one on the piece that is just to the right of the big spring near the bottom left of NSD's exploded photo:


Once I get that resolved, I'll dig into whatever else is still leaking...

[XEMON]

I have the spec at home on my computer, so that will have to wait tonight.

I also have a bunch of fresh, new ones. Let me know if you need some

[Jordan]

It's a 112 oring.

[PaintballTek]

The lower tube LPR plunger and coupler housing in a Sheridan/Typhoon is a -113 o-ring not a -112.

-112 is for bolts (or -111 if you prefer a looser fit)

That being said, a -112 will sometimes work for lower tube, but with the marker using higher pressure than most modern setups there is a decent chance a smaller seal will leak in that application.

[Yellow5]

Thanks for the guidance guys, I'll see what I can dig up locally to seal it up.

[Jordan]

The lower tube LPR plunger and coupler housing in a Sheridan/Typhoon is a -113 o-ring not a -112.

-112 is for bolts (or -111 if you prefer a looser fit)

That being said, a -112 will sometimes work for lower tube, but with the marker using higher pressure than most modern setups there is a decent chance a smaller seal will leak in that application.

See, it's true... if you don't get an answer on the Internet just post the wrong one.

I've used what i thought was a 112 on the last couple of brass semis, must have been a 113. My apologies if I misled.