FX FX Crown regulator??

These regulators are frail. It does not need much to make them leak. Adjusting reg pressure will cause the sealing surfaces to abraid. One surface is plastic and the opposite surface is brass. Both are soft materials and easily damaged. jps2486 is also correct, but what he did not say is what a pain it is to change these O rings. Be very careful not to scratch the cylinder wall surfaces while picking them out.

FX has an IPB on their website that gives you the correct size and material of these O rings, O rings are perishable and you should keep on hand replacements for every O ring in use for every air gun you have. They are cheap and well worth keeping them on the shelf. Always use silicon oil on your O rings, never petroleum oil. It is also possible to re-polish these sealing surfaces, but you must use 3M polishing cloths, never sandpaper.

Also pay attention to the Belleville spring stack orientation for re-installation. Have no doubt, this is a real PITA job!
 
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These regulators are frail. It does not need much to make them leak. Adjusting reg pressure will cause the sealing surfaces to abraid. One surface is plastic and the opposite surface is brass. Both are soft materials and easily damaged. jps2486 is also correct, but what he did not say is what a pain it is to change these O rings. Be very careful not to scratch the cylinder wall surfaces while picking them out.

FX has an IPB on their website that gives you the correct size and material of these O rings, O rings are perishable and you should keep on hand replacements for every O ring in use for every air gun you have. They are cheap and well worth keeping them on the shelf. Always use silicon oil on your O rings, never petroleum oil. It is also possible to re-polish these sealing surfaces, but you must use 3M polishing cloths, never sandpaper.

Also pay attention to the Belleville spring stack orientation for re-installation. Have no doubt, this is a real PITA job!
Exactly what I didnt want a PITA. thanks for advice.
 
HI,
If you are going to replace the regulator O rings may I suggest that you watch the video below. Sub12Airgunners are among the best at explaining how to do things on airguns. I also suggest investing in some "Jeweler's Glasses" to help you when working on the O ring in the receiver body.
By the way, based on your description of the problem it doesn't necessarily have to be the O rings. Watch the video and he tells you where the air will leak for each O ring failure. Your problem might be the regulator piston. If you have an older rifle it will be made of delrin. The newer ones have a brass piston with a delrin cap. If the mating surfaces are worn or gouged, then the regulator will not function. That sounds like your problem. By the way a whole new regulator isn't all that expensive (relative to how expensive the rifles are).
Cheers,
Greg


Here is the regulator video. It shows work on an Impact, but the regulators are the same as in the Crown MkII and late MK 1's. If you have an early Mk I Crown you will have a smaller diameter regulator. Utah Airguns can tell by your serial number what parts you need.

This is the Jeweler's Glasses I bought. I found them very useful.
 
HI,
If you are going to replace the regulator O rings may I suggest that you watch the video below. Sub12Airgunners are among the best at explaining how to do things on airguns. I also suggest investing in some "Jeweler's Glasses" to help you when working on the O ring in the receiver body.
By the way, based on your description of the problem it doesn't necessarily have to be the O rings. Watch the video and he tells you where the air will leak for each O ring failure. Your problem might be the regulator piston. If you have an older rifle it will be made of delrin. The newer ones have a brass piston with a delrin cap. If the mating surfaces are worn or gouged, then the regulator will not function. That sounds like your problem. By the way a whole new regulator isn't all that expensive (relative to how expensive the rifles are).
Cheers,
Greg


Here is the regulator video. It shows work on an Impact, but the regulators are the same as in the Crown MkII and late MK 1's. If you have an early Mk I Crown you will have a smaller diameter regulator. Utah Airguns can tell by your serial number what parts you need.

This is the Jeweler's Glasses I bought. I found them very useful.
Previous owner said it has brass piston reg. Im not really sure I want to work on it as I dont really have the extra tools needed for reg removal etc and if going to mess with might as well get a complete reseal done.
 
The alternatives are to 1. Send the gun out for repair, or 2. Buy a new regulator for $120. Personally, a dollars worth of O rings is a good choice for me.
Well if those o rings are failing then more then likely the rest of them are in same condition or close. Id rather have a complete reseal done then at least have peace of mind that its not going to mess up when I least want it to.
 
You can get a replacement kit from Utah Air guns. I would call them. I've done regs on FX air guns before and it a pretty straight forward job. You don't need a complete reseal, but hey, it's not my air gun.
If some o rings are dried out going bad do you not think that more then likely others could be in same condition.
 
Don't forget to "maintain" the o-rings
Just did lube job on my Two.
Mind you not every O-ring even if it have less than any FX i am aware of, but just the heart, so valve and immediate surroundings and regulator.

Took me about 30 minutes to do, pressured back up to the 240 BAR i had, and put away with reg pressure of 61 BAR, and pressures was the same 30 hours later.
 
If some o rings are dried out going bad do you not think that more then likely others could be in same condition.
Possibly, but O-rings in a regulator tend to degrade more rapidly than elsewhere in the pressurized system, particularly those on the high pressure side. Meaning those toward the narrow end of the piston. Why is that? Because of thermal stress of the refill cycle. Heat essentially cooks the elastomer and it becomes hard and brittle over time.

This embrittlement is the most common form of “drying out” that occurs. However there is also a slower form caused by oxidation. Lubricating seals with silicone grease slows this effect to some degree by reducing the rate of gas diffusion through the material.
 
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