My FWB 800X has been put aside for about 5 years with the air cylinder empty ( big mistake ? ). I took it out today to fill it up, all apparently went well , at least the pressure could be built and there was no hissing sound indicating leakage. When I checked it after about an hour , the pressure dropped to zero. When I tried to fill it up again, air was escaping freely through what seems to be a bleed hole on the cylinder ( see the photos ) . There is one such hole near each end of the cylinder. I believe it's a safety feature to prevent building up of excessive pressure but I filled it up to just about 120 bars today and the rated pressure is 200 bars. Now I need to fix it but I could not find any exploded diagrams of the cylinder on line. Does anyone know the structure inside ? I hope I will just need to replace a bust disc or something alike. Fingers crossed .....
FWB Feinwerkbau 800X air rifle cylinder
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I may be wrong but my experience with FWB pcp cylinders is the will not support them with parts and a replacement cylinder most likely will be where you end up. I just went through this.
I called most of the tuners and all said no to touching them. One said he stopped because it was about 50/50 destroying it trying to get it apart.
Here is a link for new.
I called most of the tuners and all said no to touching them. One said he stopped because it was about 50/50 destroying it trying to get it apart.
Here is a link for new.
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Basically. The rifle had been left in a garage for several years. I aired the rifle up and it lasted about three shots and just dumped air.
This was a p70. Not sure on the age of you 800 but the p70 ended up needing a full reseal. The reg seals and plenum seals had also perished. Fortunately I was able to rebuild it myself.
This was a p70. Not sure on the age of you 800 but the p70 ended up needing a full reseal. The reg seals and plenum seals had also perished. Fortunately I was able to rebuild it myself.
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I would get in touch with Davis Slade. Or Motorhead here in the forum. Here’s David’s info. For motorhead, send him a PM if he doesn’t chime in here. https://www.airgunwerks.com/tunes.html
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Your issue is the that the internal O ring on the cylinder end fitting is leaking. The ring that seals the end cap to the cylinder wall.
WildCJ called it, those cylinder end fittings are in there gorilla tight, I scrapped a P70 cylinder trying it myself.
Buy a new one, or if you are not competing and need an in date cylinder, a used cylinder is an option if it holds.
WildCJ called it, those cylinder end fittings are in there gorilla tight, I scrapped a P70 cylinder trying it myself.
Buy a new one, or if you are not competing and need an in date cylinder, a used cylinder is an option if it holds.
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Well that’s not good. Here’s a link to a replacement. Doesn’t look to be very expensive. A lot less than I thought it would sell for. https://www.champchoice.com/mc-airg...u-fwb-long-air-rifle-cylinder-silver-32020201
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Unless you make the tools yourself, you could have that much invested just setting up to remove the cylinder ends properly.
I actually thought that they cost more as well.
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Can you share some more info on :
1) how you have tried to remove it ?
2) how it broke ? did the end cap break or something else ?
3) I suspect the end cap is glued to the cylinder , did you see the sign of any glue ?
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I was told the threads suffer galling trying to get them apart. I had two that were bad and had already ordered a new one so I went ham trying to get them apart just to see.
I had the fill end of one so hot with a touch that the clear lens on the other end fell out. Never go any smoke from locktight burning off. But the far end did smoke and the pressure gauge unthreaded by hand. I never did get the ends caps to budge.
The one tuner said he has special tools and is 50/50 on the threads messing up.
FWB stamps them with expiration dates. If yours isn’t expired try calling FWB for a replacement. If it is past expiration they are going to say replacement is the only solution.
You could also have a custom cylinder made. I have two p70 that have custom cylinders. One uses a huma in the cylinder and the old reg as a plenum.
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Same experience as above.
The cylinder end pieces are aluminum, and on the fill end the holes to accept the 4 drive pins in the removal tool are not drilled very deep.
Cylinder was clamped in a sized collet and a breaker bar was used to turn the removal tool. I made a witness mark, and then managed to do nothing more than mangle the end cap to the point that the only remaining method of removal would be boring it out. It did not rotate at all......
Heat= no effect
Lots of rotational torque= no effect
The cylinder end pieces are aluminum, and on the fill end the holes to accept the 4 drive pins in the removal tool are not drilled very deep.
Cylinder was clamped in a sized collet and a breaker bar was used to turn the removal tool. I made a witness mark, and then managed to do nothing more than mangle the end cap to the point that the only remaining method of removal would be boring it out. It did not rotate at all......
Heat= no effect
Lots of rotational torque= no effect
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