QuestionRE: B&S model 170402, Type 0714 on a Simplicity snowblower.
A few weeks ago I cleaned the carburetor and the engine started up fine, but when I hit the snow, the engine began to die. If I pushed down on the handles so the front end lifted, the engine would speed up again. It only did this a few times.
I made some carburetor adjustments, but that seems to have made things worse. The engine now starts and idles fine, but within seconds of pulling up the handle to engage the auger, the engine stalls. If I can disengage the auger quickly enough, the engine will speed up to normal idle.
I did have the needle valve on the under side of the engine backed out 1 1/2 turns, and the idle valve on the side, near the top, turned out 1 turn. This was in an old B&S manual.
I read elsewhere the idle valve should be out 1 1/2 turns, the same as the needle valve. Could having this out 1 1/2 turns cause the engine to stall when the auger is engaged? Again, this is the idle valve on the side of the carb, near the top.
How about the idle speed adjustment screw? What part would this play, if anything in the stalling?
AnswerHi Jerry
When you cleaned the carb, did you make sure that all jets and ports were open? That is a common mistake that is made. One thing that could be happening is that the engine is starving for fuel under a load. Re-check the carb for the above. Another area to check is the magneto arms and flywheel magnet for rust and/or trash buildup. This could cause a weak spark. 1 1/2 turns on the needle valve and 1 turn on the idle valve is the correct starting point. The needle valve adjustment should be the one to work with above idle speed. Turning out supplies more fuel and in is less fuel. Hope this helps.
