- Twin Lake, MI
247.38908 Mower Won’t Start
21″ Model# 247.38908, B&S 6.75 HP
Will not fire at all. Doesn’t even try. This mower is 3 years old, but has maybe 6 hours use…it’s like new. Things I have tested/tried:
1. New spark plug is sparking well. New air filter.
2. Carb clean and rebuild kit done, but everything looked fine, like new, clean and nothing was plugged. Can see light through the jet.
3. Oil was full,clear, and clean, but I changed it anyway.
4. I tried putting a shot of gas straight into the spark plug hole, then quickly replacing the plug and wire and cranked it. Nothing, not even a little pop of trying to start. A small puff of white mist came out of the exhaust once or twice.
5. I removed the spark plug and placed my thumb tightly over the hole and had someone else pull the crank and felt no suction or compression at all. Not the slightest burp or anything. When cranking it fully assembled it sounds normal though. You get that puff puff, chuh, chuh, sound.
All linkage and cables are clean and move freely. There is nothing to adjust on this one. No needle valve or anything on the carb. It’s just a tube with a single jet sticking up in the middle of it, and going down into the float bowl (which is also working fine, filling with gas).
I would sure appreciate any help with this. Is there something I’m missing? Some pollution control valve that may be stuck or something?