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FX Impact MKII power plenum leak

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M

Macipod

Member
Dec 31, 2019
90
1
Madrid, Spain
I have a Impact MKII that bought in september 2019. When was available the power plenum I bought and fitted. I have a permanent air leak from the white pur oring. I have refitted a lot of times -actually I'm a expert dissasembling the Impact- fitting a new oring but I have air leak again and again. 

I have confirmed that the leak comes from the white oring. The air leaks from the power wheel, its practically inaudible although can be heard a very little leak, and I can see the loss of pressure in the pressure gauge (50-60 bar daily). 

The oring it´s fitted very cautiously so I don't know what's the problem. 

Anybody knows what's could be the problem??

thanks



 
What white O-ring? I attached a diagram so you can tell us what o-ring it is. Are you absolutely sure it's the right size? Do you lube it lightly with silicone? 

Even a teeny tiny little scratch or cut in the oring can cause a leak.

I feel you pain, good luck.

Stoti. 

1592233307_12626624935ee78d5b761a39.99235231.jpg

 
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In the diagram would be B 25.1. 

The first time fit the oring that comes with the plenum kit. 

Second and third time I have fitted a brand new orings bought from krale.shop, Every time has the leak, more or less leak but leak. 

Yesterday I have fitted a brand new oring -fourth- and again there is air leak. 

I have tried everything: I have lubed with silicone the oring, without silicone to avoid movement, two orings, etc. I have disassembled the gun 20 times, more or less, and every time leaks. 

I have touched the rod and seems smooth so I think that this its not the problem, but I´ll try polishing with 3000 grit. 

I'm thinking to varnish with lacquer the rod to increase rod diametre for a tighter adjust with the oring


 
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Maybe when you removed the faulty orig you inadvertently scratched the base of the tube where the ring seats. If you did, even a small scratch would also cause the air to leak.

It happened to me on a MK1 and I had to order a new tube from fx.
Click to expand...

No because I have removed the oring from the outer side, so I can not have scratched the inner side of the plenum. 


 
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If you are disassembling that far you should also replace the B25.2 and the B22 closest to the power wheel or both of the B22’s.
Click to expand...

Yes, I have replaced the two orings B22, and the B25.2. Ernest Rowe have said me that he had the same problem the first time that he fitted a power plenum and was the B25.2 that had moved 1mm or so, and then leak by the rod hole, but I have tried to fit another orings very cautiously and the problem persist.




 
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Thanks Biohazard! I didn't realize my diagram was so small or crappy! 

Macipod --- Just because the leak is coming out of the power wheel dial doesn't mean the only leak is coming from B25-1. Ultimately the air could be slipping by B25-1 but it could be that high pressure air is coming from somewhere else. The best advise I was ever given as it relates to the Impact is to change every O-ring that's accessible every time you take it apart. Some might say that's too expensive, it really isn't and will save you O-ring changes in the future while at the same time fixing problems that you thought were a certain O-ring but were in fact caused by a different O-ring. Get what I'm saying? You diagnosed the problem as B25-1 and keep changing the O-ring with no positive effect. Change them all on the valve rod, valve housing, plenum tube, etc. and I bet the problem will stop! Give it a try. It's worth the few extra dollars in O-rings!

One other thing, sometimes the scratches or small marks that make an O-ring leak can me miniscule. I've had some so small that I couldn't even see them without a magnifying glass. Use something as soft as possible and not too pointy, that will still get the job done to remove and install the O-rings.

Oh, one last thing, stock up on O-rings and other similar type parts. Nothing is more frustrating than having a leak that is easy to find and fix but then not having the O-ring or small part to fix it. Good luck man. I have been there and know how frustrating it can be, it totally sucks! You'll find and fix it! Impacts are going to leak but that's the price you pay to shoot the most revolutionary, powerful, accurate, modular, high capacity, upgradable, quiet, and super sexy gun out there!!! If you have all the parts and O-rings on hand to fix it in the future, you'll be good to go!

Stoti
 
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