S400 cylinder disassembly

[alsand]

Hi, everyone.

I need to polish the interior of the air cylinder of my S400f classic to remove some rust, but I'm having trouble removing the filling valve assembly (S472K) and fill valve body (S491).
Since it was pretty easy to unscrew the tube from the main valve body (trigger side) I assumed it would have been just as easy to unscrew the opposite side.
But the parts would not budge, both S472 and S491 are stuck together, and so is S491 to the cylinder.

The pin wrench I'm using on the S491 body is pretty short and I cannot apply too much torque. And I don't want to damage the blueing on the cylinder...

Suggestions, anybody?

Alessandro

[kevingambrell]

Warm the ends of the cylinder with a hair dryer, you want enough heat so its uncomfortable to touch.
Keep it warm for a few minutes and while its hot try to undo it again.

[Geordie]

As above.
Heat is your friend here!

[Kev Todd]

A large pair of 90 deg circlip pliers (trim to size) and a pair of rubber gloves.

[alsand]

Thanks for the suggestions.
This coming week-end I will empty the cylinder again, apply heat and see if I can get the fill valve assembly loose.
I'll keep you posted...

Alessandro

[raygun]

One of these may help.

Strap wrench.
http://www.ebay.co.uk/itm/BOA-Constrict ... 540e0265c6

ATB
Ray.

[billywhizz]

have a look on the xtx website their is a link to you tube and a vid of how to remove them,i used 4 pins the right size to fit in the the valve ends and a vice to hold the tube in , when you try too undo the valve ends a sharp tap on the spanner /grips will free the vice like grip that holds them in.good luck with your strip down.

[alsand]

Success

I ended up using a combination of the above...
First I wrapped the cylinder in a silicon foil for protection, using a pair of hose clamps to provide additional grip.
Clamped it in a vise, heated with a soldering hot air gun, and removed the fill valve using a large spanner wrench.
The remaining cylinder cap proved much more difficult, had to use a pin wrench (not sure that's the right name for it) filed down to fit.
Again heated with the hot air gun, then whacked the wrench with a mallet until it began turning free.

Having completely disassembled the cylinder, I then went on polishing the interior, and installed an Altaros regulator.
But I'll save that story for another day/thread

Oh, and I had to replace the large o-ring since it was badly twisted...

Alessandro

[kevingambrell]

Im glad you got the job done OK.
My feeling with AA is they lock tite what they cant easily anti tamper in the hope it will prevent people working on the rifles.
What cant be locke tited or anti tampered the murder up as tight as they can.
I love the Airarms rifles but this is the one part of the product that bugs the tits off me.
I suppose im farily lucky in having a full machine shop to work in both at home and at work so I can make or mend any thing I need
when im working on these rifles. But most people dont have the access to machines so they are stuffed for working on thier own rifles.

[Blackbaronfish]

The cylinder has nothing to do with anti tamper...but it has a lot to do with safety and keeping things tight.

BBF