QuestionAfter reading yours (and others) advice, I realized my carburetor needed cleaning on my 8HP Briggs & Stratton engine (model 191707). So I took it off and cleaned it with wire brush and spray carberator cleaner.
It started up! I ran it for about an hour, testing out the mower. The next week I filled the tank with gas in preparation for mowing. I noticed a small oil leak below it in the shed, not a good sign.
It didn't start. In fact, raw gas spewed from the muffler as it turned over. Upon inspection I saw that pretty much every seal and orifice on the carburetor was leaking gas. Before long, the air filter was leaking gas (its top is slightly below the gas tank top). I drained the gas and there it sits. Currently another oil leak is collecting under the engine.
Obviously I did something wrong and gas is backflowing through the carburetor. What did I do wrong? How do I fix it?
AnswerEither the float is bad, or the inlet needle/seat is bad. Usually if the float is bad you can hear liquid sloshing inside it.
Needles are aonther story, but they frequently turn hard/brittle with age; not the whole metal needle, just the viton tip that is suppose to seal.
I always replace both the inlet needle and seat with every carb rebuild. The needle is a simple remove and replace, no tools required. The seat is much more difficult to replace. You have to use a puller to remove the seat and then press the new seat in place.
My advice: check the float, replace the inlet needle, change the oil and see how it works.
Let me know if you have any other questions.
Eric
