Smkpr900w .22

[Gerard c.]

I wonder if anyone could supply some information please? I recently purchase a second hand SMK PR900W pcp air rifle with air bottle scope (Hawke 4-12x50 Ao) plus other bits for a couple of hundred quid,The gauge has dropped to the low yellow pressure mark so inserted the quick fill probe SLOWLY turned on air it went everywhere but in the fill valve, bought a new quick fill probe same problem Had bottle filled still same problem, Would I be right in thinking I have an inlet valve stuck/faulty? Does this mean it has to go back to SMK?On this model the quick fill probe slide in horizontal i notice on some the probe goes in vertical coming to rest against the barrel

[Lightning1981]

Have you closed the bleed valve on the bottle?

[secretagentmole]

Have you closed the bleed valve on the bottle?

Quick smear of Moly on the o rings on the probe may help as may new o rings!

[peddy]

Had same problem with a Webley raider. Mine was a sticking inlet valve. It got better with a quick blast of air, but be careful. It still needed sorting in the end as it still leaked when trying to fill. Check your o rings as mentioned first though

[SuffolkRifle]

Quick smear of Moly on the o rings on the probe may help as may new o rings!

Moly? Thought silicon grease was the way with O rings?

[Gerard c.]

Yes the bottle is fine filled an airarms with it,what sort of lubrication is this silicone? Is it available from a motor spares shop?

[peddy]

Yes the bottle is fine filled an airarms with it,what sort of lubrication is this silicone? Is it available from a motor spares shop?

It's silicon grease you need, though as I mentioned if the o rings look ok it will definitely be the inlet valve

[Bjacobs571]

Does your fill probe got the orings at the end to limit how far the probe can go in. It is the same probe as used on the PPW700 and that has a larger cylinder. If it doesn't try it with a small gap between the flange and the cylinder
Also is the pressure gauge on your he rifle tight. If it isn't then the air will come out of the joint between the cylinder and the brass fitting the gauge screws into. If the non return valve in the cylinder was faulty it wouldn't leak air until the probe was pulled out.

[Gerard c.]

Both the probe that came with the rifle and the new one from smk did not come with extra o rings fitted to the probe to limit how far you push it in, have fitted 2 still same problem, will try silicone this morning, if the valve is stuck can you get a replacement any where?

[gingernut]

Try cocking the the gun before you fill it.
If that fails then you have a seal or valve problem and it's time to find a gunsmith.

[Gerard c.]

Any reccomendations, as to gunsmith that might take it on?

[Bjacobs571]

This is a picture of my fill probe as from the factory
https://flic.kr/p/SGXvLo
Where is the air actually leaking from?

[Gerard c.]

1st) The 2 extra seals I never had on either probe even the new one I bought via "pelpax", the one,s that only let you push probe in so far,2)leaks either side of the intake valve where you push the probe in,

[Bjacobs571]

The two orings are about 3mm thick I think if you push the probe in up to the shoulder on a ppr900 the air will leak out during filling. Try with a 3 mm gap between the shoulder and the cylinder and see if that helps. If not it probably the orings in the grooves are damaged and leaking although I would be surprised if the orings on two probes were damaged especially as one was new. If it is leaking out of the hole where the probe goes in it has to be that the orings on the probe are letting the air past them. They should hold the air in even when the cylinder is full and a stuck non return valve will act like the cylinder is full but not let any air into the cylinder.

[Gerard c.]

Think it is time for the ole gunsmithThere is something up Will send to Will in Swansea see what happens.
THANKYoU everyoneSpecial thanks to Bjacobs571