Possible problem with main trigger on Iwata Revolution HP-CR

Yes! The valve will get dirty and debris from both the paint backflowing along the needle and into the valve area and from contaminents in the air.

Refer to your owners manual for proper break down procedures and reassembly. If you don't have them, they can be found online.

I've never removed the air valve from my CR and only recently pulled it out of the eclipse for a cleaning because it was sticking.

Get some needle lube and use it. It will help greatly in keeping paint in front of the packing and not in the air valve. After a while a small snugging of the needle packing will restore it's sealling capabilty, also keeping paint out of the air valve area. Don't over do it or the needle will not move freely.

JButler wrote:

When I push it down, I can see that it opens the air inlet on the bottom of the brush, but when I pull up on it, I have about a quarter inch of play in it.  When you pull up on the trigger, does yours have some play in it?  I seem to recall that there wasn't any play in there when I got the gun.  I hope that I don't have to disassemble the air valve.

Are you saying that you now have some fore-aft slop in the trigger when you draw back on it for paint flow? If this is the case, it has nothing to do with the air valve.

In removing the needle chuck guide, you would have to first remove the spring guide (part 14). When you reassembled the brush, this part may not have been screwed into the body sufficiently.

Loosen the needle lock nut (#16) and turn the spring guide clockwise to screw it further into the body of the airbrush. This should take up the "slack" in the trigger movement. Do not over-tighten as it may lock the trigger closed.

Note that there is some latitude in how far you tighten the spring guide to allow you to vary the spring tension in the trigger.

Re-seat the needle and retighten the needle lock nut.