I recently bought a used airgun and it arrived with the regulator at the same pressure as the airtube (220bar). I was told to shoot it to see if it would straighten it out (it was very loud when fired) but it didn't fix it as suspected then it went down to ~200bar but still same pressure as the rest of the air reservoir. Is the regulator damaged in any way if this happens or is it something easily fixable?
FX What causes regulator to be same pressure as the rest of the air tube?
- Thread starter jem91
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I gave up on the FX AMP regulator and replaced my 3 with Huma Air regulators. 1 did as you describe, one creeped and the 3rd leaked. Mine had thread lock so rebuilds would have been a pain.
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If the regulator is at the same pressure as the air tube (or bottle) it means the regulator is not working. New O-rings may fix it or even just getting the right amount of silicone grease on the existing O-rings.
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is it just bypassing the regulator completely and the regulator is showing the reservoir pressure instead? Because that regulator isn't supposed to go anywhere near 220 bar that it was at before i shot it a few times.
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There's not a huge plenum to hold thermally expanded air on the dreamline. More than likely the delrin piston in the amp regulator is divoted.... Its a problem with them that I chased on my impact for a long time. My dreamline is good thus far but when it happens I can only give you 1 suggestion.
Just buy the huma regulator and eat the tarrifs. You WILL NOT REGRET IT. They stay rock solid as set on a digital guage and I've been extremely pleased.
It's a simple replacement that will require some metric Allen wrenches to remove the fx reg, some silicone grease or oil which may or may not be provided, and a flat screwdriver in 2 sizes if it's still made like mine.
I recommend pulling the bottle and degassing the gun ASAP, you don't want bottle pressure extruding any orings and causing a rebuild.
The other option is replace the delrin piston and face the issue again later potentially. You can only adjust them up under pressure if memory serves or the piston gets damaged and does this. Keep close track of the way the Bellville spring washers are stacked, this order is important for the spring rate.
Is yours 22? What pressure do you intend to run once fixed? Revisiting your Pic I'm guessing 22 compact tube.
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Just looking at the barrel it looks like an earlier model . 
I agree with the others it is bypassing the reg .
I agree with the others it is bypassing the reg .Upvote 0
I was thinking compact tube gun if regulated, but you have me 2nd guessing now because I think I remember reading that barrel attachment was improved on later models like the one I have and some super thin shroud, like I have. It's a rock solid barrel, but the shroud doesn't do a lot to help quiet anything.Just looking at the barrel it looks like an earlier model .
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I highly recommend getting a huma reg. They have washer stack instructions on their page. It should come in parts in a bag but the removal and installation is very modular. Almost like a cartridge. Very easy to do if you have any mechanical inclination. Memorize the instructions on how and when you you can adjust it, watch the oring contact surfaces and you should be in business in about 15 minutes I think.... Depending on your comfort with machines. Or just come back here and im happy to try and help.
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yes you are correct the shroud od was decreased in in size to the much smaller ones . I ran one in 320 mm length on 1 of my crowns for a few years and thoroughly loved it lol . No poi shift what so ever for me anyway .
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I've got three FX rifles that take the same AMP reg. I have 4 or 5 of the latest AMP reg's and 4 or 5 of the HUMA w/ all the different washer stacks. I've used all extensively. Both have pros & cons. If I had to choose.....I'd choose the latest AMP. I get just a tad better consistency. Both reg's use delrin seals, so no real difference there. Honestly you can't go wrong with either. I even use an AMP w/ the delrin piston as the 1st reg on my Wildcat and it works fine. The only real pluses of the HUMA has is the power range can be more narrow which theoretically would result in better consistency, but isn't proven in real life. Also, the replaceable delrin Disc. The answer to that is keep a spare AMP piston.
Every reg will periodically need rebuilt. I've had to rebuild both about the same amount.
Every reg will periodically need rebuilt. I've had to rebuild both about the same amount.
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I don't know about FX but Huma offers reasonably priced rebuild kits for their regulators. But it's just the O-rings you need and a sealing disc or two. They also offer the discs separately. If you can buy something like this for the FX it would be my next step. But when the Huma in my new Caiman failed it only needed silicone grease in the right amounts in the right spots. This gun is used, however, so O-ring replacement seems appropriate.
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I've been messing with regulators for awhile with some success. But I had to think about what was going on more with a couple SPA regulators that were not working and I think I finally understand basically what is going on with the regulators I have in my SPA guns which work the same as the Huma in my Caiman.
The basic functionality is just a piston formed by the shaft the spring washers are on that has a plastic disc on the top that interacts with the end of the adjustment screw. The "piston" closes the valve formed between the plastic disc and the end of the stem when the air pressure in the regulated chamber raises high enough. The spring washers are pushing to open the valve. So if you increase the force from the washers by turning the adjustment screw clockwise it takes less pressure in the regulated chamber to close the valve. That's why you turn clockwise to lower the regulator. I think it's a good idea to make sure you can easily move the stem with the washers up and down after you finish servicing a regulator. The air has to be able to move it. There will be a little resistance but if there is too much it won't seal and the gun will be unregulated. That is what happened to my SPA regulators. I didn't put enough silicone grease on this area.
The basic functionality is just a piston formed by the shaft the spring washers are on that has a plastic disc on the top that interacts with the end of the adjustment screw. The "piston" closes the valve formed between the plastic disc and the end of the stem when the air pressure in the regulated chamber raises high enough. The spring washers are pushing to open the valve. So if you increase the force from the washers by turning the adjustment screw clockwise it takes less pressure in the regulated chamber to close the valve. That's why you turn clockwise to lower the regulator. I think it's a good idea to make sure you can easily move the stem with the washers up and down after you finish servicing a regulator. The air has to be able to move it. There will be a little resistance but if there is too much it won't seal and the gun will be unregulated. That is what happened to my SPA regulators. I didn't put enough silicone grease on this area.
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I will modify my previous opinion. Any reg with a brass piston. New amp or huma. With the impossibly small holes in the pistons, id rather mess with flipable inexpensive delrin discs as the wear item than the piston itself.
I call stuff that is low effort and low expense to make "dumb parts". The delrin discs that go with the brass pistons are dumb parts, easily made which is why i like them.
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Try using some Airgun Butter Lube on the whole regulator sold by Warren at Air Shootist. It's made exactly to possibly fix this kind of problem. Its $30.00 for 1 ounce but a little goes a long way. I've been using it for awhile and it seems to work great!
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A regulator doesn't close when the tube/bottle pressure falls below the reg set pressure...so tube press=plenum press in that case
Maybe the former owner turned the set pressure all the way up to the 200 bar ?
Thinking to actieve max power by doing that?
(A lot of People seem to have not a clue what they are doing)
small change that someone woud do this this or if it's even possible to set it to 200 bar ...but you never know and would be worth a try to lower the set pressure before ordering new stuff
by the way these New amp regs are just fine ( i own a crown and adreamline) . No creep at all
Maybe the former owner turned the set pressure all the way up to the 200 bar ?
Thinking to actieve max power by doing that?
(A lot of People seem to have not a clue what they are doing)
small change that someone woud do this this or if it's even possible to set it to 200 bar ...but you never know and would be worth a try to lower the set pressure before ordering new stuff
by the way these New amp regs are just fine ( i own a crown and adreamline) . No creep at all
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