Cleaned the needle valve and tried the blow test. The pin on the valve hangs down about 1/8 inch or so. About half of that is free play. The valve closes just when the spring is felt. It tests OK when the lid is in the normal position but if I flip it over just the weight of the pin (no float attached) is enough so you can't air blow through. Is that correct or is the spring too weak?
BTW noticed alignment of the hose bib of the banjo with one of the holes in the bolt causes more air (gas) flow. If the holes are off and the lap of the filter screen happens to cover the hose bib hole, it flows way less. Maybe because my screen is out of round, not new, just cleaned.
Hope I don't need new needle valves - ZTherapy doesn't list it on their site and MSA only shows it in the kit, one $30 kit per carb. If the spring is weak can/should you stretch it a bit? Maybe OK but it's my first time with that thing. Last night before cleaning it the blow test was intermittant - don't remember if the lid was level or not.