Question I have an old Sears rototiller the motor is painted red, if that helps. I can find a mod #143-547012 on it. I need to know what the three carb adjustments should be set at and what there function is. There are two adj on the bottom of the float bowl. One on the center screw the other is on the laft side. This one has a small spring on it and is probably sticking out about 1/2 an inch. The third adj is on the left side about intake manifold level.
THANKS for any help you can send me,
AnswerGo to the Sears web site, click on "Parts", type in the model number and go to the carburetor diagram.
This should take you to the site:
http://www3.sears.com/
Part #6 is the idle screw, it sets the engine idle RMP.
Part #7 is the idle/air mixture screw.
Part #21, the one on the bottom of the float bowl is the high speed misture adjustment.
The idle and high speed mixture needles are turned out 1 & 1/4 to 1 & 1/2 turns from a gentely seated position, usually finger tight. If you over tighten the idle mixture screw you can damage the carburetor.
After the initial adjustment, start and warm the engine. Adjust the ilde mixture screw until the engine runs the smoothest; turn it in a little until the engine starts to run rough, then turn it out until it runs rough and finally set it in the middle of these two points. The engine should idle smooth.
Use the same procedure on the high speed jet. Once you have it set you may have to adjust it a little once you start tilling.
Let me know if you have any other questions.
Eric
