I used 72cc plenum and power block on my mk2, but the plenum recovery is too slow, guys how can i fix this problem, i change the factory regulator to huma air, the recovery was way too slow ..
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Tuning , fx impact mk2 very slow plenum recovery
- Thread starter Jacobpc
- Start date
I had that same problem was driving me nuts. After 3 years of the AMP reg being great it suddenly sucked, the Huma is good so far though.
Edit, tried new piston, new washers and new orings throughout the reg.
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Try reducing the regulator’s setpoint by 20 bar or so to see if its recovery time improves. If so, that suggests the Belleville spring stack is too weak for the original setpoint (the seat can barely open).
Otherwise disassemble and see if the end of the piston is indented badly. Also check that no debris is trapped somewhere feeding to the orifice (place the end of the piston meets).
Otherwise disassemble and see if the end of the piston is indented badly. Also check that no debris is trapped somewhere feeding to the orifice (place the end of the piston meets).
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hmm. this is concerning to read. My mk2 is headed to fx for warrantee repair on the pin block that aligns the barrel to transfer port. I figure if I got to send it in and be without it for a few weeks, FX might as well upgrade my MK2 to the 720 plenum and new power block. I mainly shoot self-cast slugs so more power the better. I'll update when I get my impact back on how well it behaves and what I see for recovery rates. I'm sure they will go through it and get it back to me in a polished and usable state.
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I had the exact problem when I installed the extra high pressure Huma regulator. What it ended up being was a change that Huma made in the arrangement and number of the Belleville washers. A change that they made in thier washer thickness required a change in the installation, so when I tried to arrange them according to the enclosed instructions I ended up with the same problem you have. I contacted them and they sent me a new set of installation instructions that eliminated one washer with a new washer orientation. Everything worked fine with the new arrangement including filling the plenum. I'm not sure which model Huma regulator you bought, but you might shoot them a message and let them know the model of regulator and symptom you are having. They may have an updated installation guide for yours also.
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fx usa currently has my impact and the order has been put in to get the work done. so a few weeks and i should have it back now.
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A member out of Poland is making a upgrade regulator piston, have 2 of them on the way to me this week
www.airgunnation.com 
Tuning - FX Impact/Maverick/Crown brass regulator piston done right
Hi. We know that a standard FX Impact regulator piston is made of delrin. It has a pretty poor coefficient of thermal expansion comparing to brass. Brass is a much better choice. It is more rigid and tough which is pretty important when we think about high reg pressures. FX offers a brass...
www.airgunnation.com Upvote 0
got word from fx. my upgrades to 72 cc plenum and power block are complete. my gun is undergoing leak check and I should be hearing from customer service to square up my bill and get the gun shipped back to me. getting excited. talked to the tech and he says it's a hammer so far.
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got my impact mk2 720 power plenum and power block back today. shot a few shots as received from FX. plenum fills with every shot. shot about 1/2 a mag in 22 cal and it only used 6 bar of air. not sure what current fps is, as it was late when I got home. need to run the numbers and check over tomorrow. things look good so far.
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