PW22 O-Ring Size

Dr. Frankenstein · Post by **Dr. Frankenstein** » Mon Apr 15, 2019 8:10 am

Does anyone have the measurements for the PW22 carb o-ring, part # 16175-260-004, and / or a source for said o-ring?

Paying around $5 plus the same in shipping for one teeny o-ring is ridiculous....I know it says "2.8mm", but is that Outside, or Inside diameters?

Geoff Hastings · Post by **Geoff Hastings** » Mon Apr 15, 2019 11:01 am

2.8mm must be the the thickness of the o-ring.

brewsky · Post by **brewsky** » Tue Apr 16, 2019 6:23 am

How about a picture of your air screw?
Some use the o-ring and some do not

Dr. Frankenstein · Post by **Dr. Frankenstein** » Tue Apr 16, 2019 4:10 pm

That raises an interesting question: it's a PW22 carb, and the air screw is the one with the rounded-off tip, with a spring in the hole.

The diagram that I have shows a little o-ring for it, but yes, I agree that some use one and some don't. No pic yet, but that does give me a pause for thought...Does this carb need that o-ring…?

brewsky · Post by **brewsky** » Tue Apr 16, 2019 4:29 pm

The one with the rounded off end is the idle speed screw, not the air screw....even they will go in either hole.
The air screw hole is closest to the engine.

Dr. Frankenstein · Post by **Dr. Frankenstein** » Tue Apr 16, 2019 4:59 pm

Huh - and here I was just following the (apparent) diagram placement - - another case of the diagram not being all too clear about what goes where! On page 40/Part #19, it looks like the rounded off one goes Farthest from the engine! I was wondering about that...

Even in this case, then, it still shows the Idle Speed Screw getting that o-ring...I'll go out and do some prestidigitation and report back; see if the "2.8" mm (OD) o-ring I have fits...but they appear to be the same size hole, so we'll see.

brewsky · Post by **brewsky** » Tue Apr 16, 2019 5:40 pm

The rounded off one DOES go farthest from the engine. That one is the idle speed screw.. It sets how far down the slide will travel when the throttle is not turned at all.
Need to see a pic of the flat nose screw to tell if it gets an o ring or not.