I have a OS .61 FSR ABC with a 7m Carb that was purchased about 1992 or 93 and has been used with a mac's pipe on a pattern plane. It hung on a wall for about 5 years, and was cleaned and run again this summer. My problem is that it will quit after idleing for more that 30 seconds. It will start and run well if you rev it up quickly, but will stall before you can get it in the air. Since all instructions have long since been lost, I need to know how to adjust the idle. Is the low speed adjustment on the opposite side from the needle valve? HELP!! Please!! Thanks!

Please look on the carburetor to see what model carb it is. Then we can possibly help you out.

The front of the carb reads -- OS 7 M. That is the only markings on the carb.

I noticed in your first post you mentioned the carb type. Sorry I missed it the first time I read it. Saw it today.

The O.S. Max #7M carb was one of the finest they made. It had high-speed, idle, and midrange adjustemts.

For intial setup, put the high-speed needle at 2-1/2 to 3 turns out from closed. This is very rich.

The idle mixture is adjusted by the small screw that has the offset head. It turns from 9:00 o'clock to 3:00 o'clock. Set it to 12:00 o'clock.

The midrange adjustment is the slotted screw (NOT phillips) that's below and just forward of the high-speed needle. Turn it in until it stops, and then back it out about 2 turns.

When you run the engine the first time after making these settings, start the engine, advance it to full throttle and get the high-speed needle set first.

Once the high-speed needle's set, retard the throttle and adjust the idle mixture. Clockwise for lean, counter-clockwise for rich. Usually, you'll wind up leaning it a hair. It doesn't take much movement to affect the idle.

The midrange is adjusted last, with the engine at about 1/2-3/4 throttle. Turn it clockwise to lean, counter-clockwise to richen.

Hope this helps you out.

Thank you very much for the information. I have printed it out, and will keep it for reference!! Thanks again.