Diana P1000 barrel leak

[MrBen]

Hi Guys, a little frustrated with this gun, had a leak from the barrel, I replaced both seals which I believe to be 11x1.5 it still leaked. I then ordered a replacement knockoff valve no change, I stripped it again checking the seals again and polishing the valve seat. Still leaks. I am starting to think the seals again and size I am using are incorrect. Any help would greatly appreciated. Thanks in advance.

 

[Fatbob 59]

If it's leaking air through the barrel then it must be a valve issue , it's the only route from the air cylinder to the barrel , the barrel O rings would only leak air when the gun is fired

 

[MrBen]

If it's leaking air through the barrel then it must be a valve issue , it's the only route from the air cylinder to the barrel , the barrel O rings would only leak air when the gun is fired

That’s been my theory, however I am now suspecting the lower valve seat seal, that would give the same symptoms?

 

[Fatbob 59]

That’s been my theory, however I am now suspecting the lower valve seat seal, that would give the same symptoms?

I'm not familiar with the gun but the problem must be in the valve somewhere

 

[Premierpistol]

It's been a while since I seen one of these myself, am I right in assuming the 2 seals you changed were the ones show as item 73 below?


If so, there could be damage or scoring to the valve face (item 74) which is allowing air to pass the stem seal (item 69)

 

[MrBen]

Thanks for you reply, all bores are good, and all o rings have been replaced twice. Valve seat is also unblemished. I have just ordered some nylon bar to make replacement knock off valve, the original and replacement I bought are very hard, possibly Delrin. Nylon being softer will hopefully make a better seal.

 

[Gympie]

Hi
Did the nylon poppit valve fix the leaking?
Thanks

 

[MrBen]

Hi
Did the nylon poppit valve fix the leaking?
Thanks

No, the problem was reg seals, once I replaced all of those, problem solved.

 

[Gympie]

Hi MrBen
I have the same problem, can you give me a bit more info on replacing the seals?
Thanks

 

[MrBen]

Hi MrBen
I have the same problem, can you give me a bit more info on replacing the seals?
Thanks

You will need to remove the reg block locking pin from the front of the block then the block unscrews, seals are then easily accessible

 

[Gympie]

Hi MrBen
Are you talking about the o-ring at the base of the belleville washer spigot? I took mine apart and this o-ring was hard from age and had a flat spot around the entire circumference.
How did you figure out it was the reg seals? Do you have a diagram of the different configuration order for the belleville washers?
Mine are thus ))(())(())(()) but I am told there are several factory options, just can't find them.
Thanks for any help you may be able to provide.

 

[MrBen]

Hi MrBen
Are you talking about the o-ring at the base of the belleville washer spigot? I took mine apart and this o-ring was hard from age and had a flat spot around the entire circumference.
How did you figure out it was the reg seals? Do you have a diagram of the different configuration order for the belleville washers?
Mine are thus ))(())(())(()) but I am told there are several factory options, just can't find them.
Thanks for any help you may be able to provide.

I replaced every seal, I could find, sounds like your problem is the one on the Belleville washer spigot. I can’t help with the Belleville washer configuration, sorry.


How did you remove the pin locking the reg assembly out of interest.

John

 

[Gympie]

Hi John
If you are referring to part 84 on the parts schematic, mine does not have the pin or grub screw holding this part in place. It is threaded with no other securing method.
My model has a brass spigot that extends into the receiver block and that spigot has a 6mm o-ring on the very end.
I made a few new part #74 seats and tried with different angles and seat width but the leak persisted. This is when I contacted you to see if you had a solution. While waiting for your reply I made a part #74 without drilling the supply hole as I was (still am) confused as to how the supply air is bypassing the poppet needle and seat. After reading your solution I went and installed the un-drilled #74 and the bloody thing stopped leaking so while this proved to me your solution is going to work, I just can't see where the supply air is coming from if the poppet and seat are not the issue.
As this is my ratting rifle I am happy to die wondering as long as the rifle is not leaking.
I am an armourer that started my life as a toolmaker so I am no genius with pneumatics but I don't want to start sleeping with my eyes open.
Not all that many air rifle enthusiasts down here and even few good techs. I specialise in BAM so the pneumatics is a new lane for me to travel into.
Thanks for your replies and assistance.

 

[Gympie]

Hi John
Another quick question, where did you get the o-ring rebuild kit from?
I found o-ring-sporting.com online and they listed a Diana p1000 kit so I ordered one.
It arrived but two of the three o-rings for the reg were not correct or missing.
The 14x2mm was actually 14x2.5mm and the 4x1mm was missing altogether.
Fortunately both are pretty standard so now that I know the sizes I can source them locally however, it would be handy to know which supplier can be relied on to provide the correct parts.
Thanks again.

 

[AirArmsDavid]

Guys... how do you remove the front stock (Evo2)?

It pivots but not enough to clear the fill valve. Cylinder removed but do I need to undo something else to get the front stock off?...





Thanks for any help.