Rebuild Question on my NP XL 1100

[Reddsunmourn]

So I have the gun all apart, but haven't removed the piston yet (ran out of time last night). My question is, how do I put the new seal onto the piston? Should I use a silicon adhesive or something less permanent? 

[mooseslayer]

If anything like my Crosman Venom it is just a press fit and very hard to get on. You might soften it a bit in hot water. I would not use any adhesive.

[ezman604]

As stated already, no adhesive needed. Once you get the piston out you will see. And as John stated, drop the new seal into a cup of very hot water for a couple of minutes to make it more pliable. Lay it on a paper towel, wash cloth or clean rag and start the piston button into the seal opening and press. It should pop into place.
Before reinstalling, take a look at this.
http://www.gatewaytoairguns.org/GTA/index.php?topic=715.msg4889#msg4889

[Germanbill]

Can you help me too? I'm new to the GTA, and have very little knowledge. I went to Gene's site, but don't see how to get the stuff I need, (or think I need!) for my NP XL 22.

Gene writes about pure silicone 30 wt. oil, and moly lube. I don't have any of this stuff and I need to know where to get it. I also need to know where to get a good rebuild kit with the piston bushing, piston seal, and brass barrel washers. Can you tell me where to get this stuff?  Thanks for helping!   Germanbill.

[ezman604]

Gene has shut down airguntoys.com due to the rising cost of postage and manufacturing. He just didn't want to pass the cost increase off on his customers. As far as proper lubes, take a look at James Maccari's website Air Rifle Headquarters for his lube package.
http://www.airrifleheadquarters.com/page/page/251484.htm

[eaguila]

if the hot water wont soften it, try a hair dryer for a few minutes, i had success with putting mine on using the hairdryer at high heat and low fan.

[Reddsunmourn]

Thanks for the help, I can't wait to get home now and finish the gun up. It shot fairly well before the tune, I'm excited to see what kind of improvement it makes.

And to the person looking for a good place to get parts and lubes, I found everything I needed on Pyramyd Air. I didn't do the washer fix yet, but with the GRT 3 trigger, it works well enough for me.

[OleTomCat]

Be careful with heating the seal you do not want to deform it in any way or your gun will not perform correctly....

If you go to Air Rifle Headquarters Jim gives a pretty good description on how to heat it up...

[ezman604]

I need to look at Jims instructions but of the MANY seals I have replaced, I've never come close to deforming a good quality seal by dropping into a cup of hot water for a couple of minutes.

[JR]

Hot water seems to work fine, I also rub my finger across chap stick and then rub the center hole in the seal. I put the seal face down on something soft yet hard, (I use a scrap piece of linoleum) and push the piston onto the seal, never really had any issues.

When you re-install the piston in the gun make a sleeve to wrap around it to protect the seal from the plug threads. I cut the ends off a "Smart Water" bottle and roll it up in it, thinnest I've seen, yet tuff. Lube the seal, roll it up so the seal is covered by the sleeve, stick it in past the threads and pull the sleeve out. Don't let the seal catch on anything pushing the piston in, de-burr everything before hand.