MS 250 carb issue

[azmtnman]

My MS 250 has about 5 hours on it (if that!) It quit running right and I put it aside a couple years ago and just got it back out to try to repair.
It would run fine for a few minutes then act like it was running out of gas so I changed the pump diaphragm. It's not as bad now but after it's warm, it won't run mid rpm--which includes getting through mid rpm to get high rpm. Once at high rpm, it runs and cuts fine as long as you keep it there.
What am I missing?

[ladylake]

 
If the low adjuster is too lean or the low circuit is clogged it will act like that.  Steve

[azmtnman]

So it has like an idle jet?

[dougand3]

Fully adjustable MS250 carbs have H, L and LA(Idle) screws. Some have fixed jets and can't adjust. Fully adjustable are available online for ~$10.