If I have an M3 but like the look of the MKII valve knob, would it make any difference?
Are the M3 and MKII Valve knob interchangeable??
- Thread starter KevinWood44
- Start date
FX includes a new adapter and spring in their conversion kit. Maybe you can swap knobs but you might as well upgrade to the Power Block/Power Plenum.
Edit: Sorry my brain read this backwards. You want to use the MKII knob on your M3? My guess is it wont work, at least not as a direct swap. There are differences in the knob and squishy rubber ball mystery. I have been trying to find a diagram of the two systems to figure out who gets the ball and where it goes lol.
Edit: Sorry my brain read this backwards. You want to use the MKII knob on your M3? My guess is it wont work, at least not as a direct swap. There are differences in the knob and squishy rubber ball mystery. I have been trying to find a diagram of the two systems to figure out who gets the ball and where it goes lol.
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I may be mistaken, but I think that they shortened it to clear the barrel clamp on the new models.
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The insides are different. M3 has two rubber balls under the m5 countersunk screw at the end of the knob. Those two balls are buffers for the step down piston also inside that valve knob. It’s purpose is to take the strike from your hammer stop(known as the C1).
With those rubber balls in place, this is why fx says not to use the rubber ball that comes in the slug power kit. The M3 valve knob piston combined wiyh the rubber balls prevent valve rod over travel.
You can switch the knobs out, but use the same M3 spring and use the rubber ball on the inside of the valve spring so the C1 has something to strike against. Go to the parts diagrams to find out the correct size of ball to use.
With those rubber balls in place, this is why fx says not to use the rubber ball that comes in the slug power kit. The M3 valve knob piston combined wiyh the rubber balls prevent valve rod over travel.
You can switch the knobs out, but use the same M3 spring and use the rubber ball on the inside of the valve spring so the C1 has something to strike against. Go to the parts diagrams to find out the correct size of ball to use.
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You can pop the guts out of the m3 knob and it will fit into the mkII power plenum knob is what I meant to say..
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I removed one of those lil balls (the little one) I was told it wasn't needed with the slug power kit. Is that correct? I hope so, bc that ball is definitely lost by now lol
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Do you by chance have an M3 diagram that shows the knob internals? I think the only time you would use a ball with an M3 knob is when converting an older MK2 from a couple assembly videos I watched. Seems to be conflicting info on this one. My MK2 has the Huma kit and the Power Block FX kit so I used one ball inside the valve return spring.
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It’s on fxairguns.com website- go to support section and download the M3 diagrams and zoom in on the valve knob area.
If you’re using the Huma valve spring for the MK2 it came with a rubber ball, right? I brought this to huma’s attention way back when and told them if that ball isn’t included it will cause valve rod over travel and when you hear that pop by your face and air hitting your cheeks with every shot it’s because the 2x1 o rings at the valve rod tip got sheared off, due to the valve over travel. Yeah, so on an MK2 valve knob with that spring or the fx slug kit valve spring the ball must be used.
Huma started adding the ball with the valve spring moving forward as in kit form.
If you use the ball on the M3 you’ll immediately lose about 200 fps, which is why fx says not to use it.
Two balls ok, three not good
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