Gamo Urban Air Pressure leak

[BluegrassBill2020]

I am brand new to air gunnery and at 82 yrs I purchased a Gamo Urban .22 PCP, Yong Heng after marker type 4500 psi Compressor. The Rifle is now 4 months old and just started to leak air pressure (1000psi over night) . I have changed the Quick Fill Body O-Ring, Using water I can detect no leak. I moved on to removing the Valve housing and changed that O-Ring also, Still leaks, Now I am up a tree, Trying to fix it myself I have voided the warranty. I have the schematic of the rifle. On disassembly I found a very small pin attached to the magazine magnet, I have no idea where belongs and can't find it on the schematic. Any idea's welcome. 

 

[Yo]

Pictures would be helpful and rubber banding a pair of balloons to the end of the barrel and filler right below would be helpful. If the barrel fills the balloon then it's probably your valve stem seal poppet then try backing the power down first and see if that helps.

Maybe you tried cranking the power too much?

Dual balloons first then you will know what needs to be done.

 

[BluegrassBill2020]

Balloons good idea. I have not done any mod's to rifle was very happy with power and accuracy. Thanks

 

[BluegrassBill2020]

Eureeka! I found the leak! It was the pressure gauge adapter leaking between the gauge and the adaptor, Replace both O-Rings and no leak I hope. Pumped the rifle to 3000 psi Its not showing any bubbles, I used soapy water on that part, Didn't have any balloons. I had been focusing on the fill port with plain water. Now time will tell. 

 

[BluegrassBill2020]

Follow up. The Gamo Urban .22 Holding pressure and shooting great again. I learned a lot about PCP Rifles.

 

[Yo]

Glad to hear you got her up and running again. It's a really great feeling to be able to fix things yourself such a sense of accomplishment!

 

[DBax8496]

That little pin you found came from between the cylinder.and the breech it is used as a locator when they bolt together. How it came out i don't know the breech would have had to been awful loose or disassembled and reassembled incorrectly at one point otherwise. 

 

[BluegrassBill2020]

I didn't measure it at the time, I guestimate 7mm X 2mm. Next time I have apart I'll look for the spot to put it. There was nothing I could see where it could fit. The Urban is working perfect now. Thanks for the info, The pin doesn't show on the schematic I downloaded. 

 

[BluegrassBill2020]

Looking closer I see the only pin small enough is located in the pellet probe bearing (Part of the bolt), Part num 16-9047 retaining Pin. That's where I put it . It was the only hole small enough to fit. I didn't push it in though, I'll tear down again and be sure. Thanks

 

[TOMVOLTS6]

i think theres a small pin about the size of lead in a pencil and about a half inch long that MIGHT hold that silver piece (with the ribs) that the trigger is attached to,in place
(not the "hammer" pin)

 

[BluegrassBill2020]

Thanks Tom, Problem was solved a year ago. LOL All Answers are always welcome. Bill