I just received my new hatsan flash along with my Chinese air pump with an air filter today. I’ve managed to plumb in the filter but as I’m a minute or 2 into pumping I can hear a leak up towards the fill fitting that goes into the rifle. I’m starting to wonder if it’s leaking where it goes into the rifle or maybe the threaded fitting (used Teflon tape on threads). Have any of you had this problem before? Maybe the orings on the fitting inside gun need lube?
Leaking air while filling Hassan flash
- Thread starter efiles123
- Start date
Check for nicked O rings on the fill probe. A little soapy water will show any leaks. Be careful with lube that might find its way inside the high pressure area and cause dieseling. If you lube I would use 100% silicon oil and very little of it. I got spare O rings at an industrial supply but you can probably get them at hardware stores. My AT44 came with some spares.
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`Here's your issue. Those threads are parallel on the fill probe. (bspp not NPT) You should have a sealing washer inside. Teflon tape is not for parallel threads. You likely have the wrong adapter too. I'd bet it's NPT. (I've never come across one in brass, only stainless or black)
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I figured something was wrong with those fittings. I just threw this together using what I found inside the box of the hand pump.
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From the photo it looks like the probe is out of plumb with the filter. Is it cross-threaded?
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Try it without the filter, some times it's the fosters fitting leaking, also make sure the bleed valve screw is tight, hatsan loves to leave those loose, it's next to the gauge, lube the probe o-rings with silicone oil, you can get at any hobby shop as silicone shock oil, any brand will due, I use 60- 100 wt, also put about 5 drops in the probe and pump into the gun, it keeps the valve seal lubed
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If I try without filter will I risk pumping moisture into gun? I’m in a relatively low humidity climate but don’t wanna take any chances.
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I also read somewhere that on a new pcp air gun with fully empty tank you can’t fill with hand pump first time. Someone to do with the air valve. Anyone know if this is true?
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Looks like I found a video explaining what I need. Anyone know if this stuff can be found at Home Depot or a local hardware store?? Looks pretty specialized.
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That's a dowdy seal. It will work and is external of the female fitting. Lowes sells some delrin washers that will work in a pinch. I think they might be like #10. I stacked 2 or 3 together and put them inside the female side.
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