QuestionQUESTION: (This is a resend per site instructions, as another expert was busy)
What would cause fuel to gush back into the air cleaner through the EGR tube? It's the Walbro carb on a 3 yr old 12.5 HP Briggs. I took the carb off the the engine, (pretty clean)sprayed it out anyway with cleaner(no obstructions, good float), reinstalled. Same issue. Runs for 10 seconds, spews gas out the EGR hose and the exhaust. I have done this twice. A good thing is that it hasn't caught fire yet!
So, I would appreciate any insight. Thanks!
ANSWER: Phil
1st thing is make sure your oil level is not over filled,that causes those symptoms.
Also your float may be sticking in the carb as it starts using fuel the float sinks down allowing fuel to pass through the needle port kind of like a shut off valve. If goes down and gets stuck that will causing flooding as to much fuel is being dumped in the carb and the carb can not handle it,something like trying to fill a small bottle from a big one. Remove the float and the bowl check to see where the needle valve is to make sure there is a very tiny o-ring in the port where the needle seats, it should be white or orange. That is the rubber seat for the needle valve. that may be missing or worn out.
---------- FOLLOW-UP ----------
QUESTION: Thanks Ben. The oil level was overfull, but it turned out to be mostly gasoline. Drained it, flushed 3 times with fresh oil, ran it. Checked oil level: between Add and Full. Took it out for a trial run and it worked OK until I ran along a side slope (right side of mower downhill) for a few seconds and it started to run rough...like it was flooding. Ran the other way across the slope, and it smoothed out. Reversed direction again, and it nearly killed. Checked the oil level, and it was above the full mark and smelled like gas.
Took apart the carb, and noted no o-ring in the float needle valve seat. But then, I don't clearly see that ring on the parts diagram (Illus. parts List 284700 model series TN0101-1150), either... could be missing it.
More details on part numbers: B&S PowerBuilt 12HP MN 284707 TYPE 1026-E1. Carb is a Walbro L2 (LZ??)-M1043-697212.
Your help is appreciated!
Answer
carb
Phil
Yes sometimes the IPL'S are not to detailed,the small grommet has to be installed a certain way also,are you needing the part # or are you missing the part. If you got a rebuild kit it was included in the kit. the part # is 690577 Seat-Inlet
