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Mend Briggs & Stratton 18.5hp twin Mower Working Start

Briggs & Stratton 18.5hp twin - petrol flooding?

My mower was working OK, but when I tried to start it after it had been standing for a couple of days, it fired ran and then stopped. After checking through the machine I removed the air filter and noticed that after running for a couple of seconds petrol started to flood from the top of the carburator, thus soaking the plugs ect. I would appreciated any advice.

David Parrott
July 2009

Briggs & Stratton Briggs & Stratton 18.5hp twin Garden Tools, Lawn Mowers Mower Working Start

Hi John

Once again, thank for the advice about the float chamber. Which in fact was the problem. What a plonker I am!!!! I have not been able to look at the machine for two weeks, but today while looking at the carb I relised there must be a float chamber. Anyway, I fixed it and many thanks to you for your advice.

Regards

David

David Parrott
July 2009

Hi John

Many thanks for the advice, however there is not a float bowl.

The fuel enters the carburator under gravity to the front of the carb, where there is a plastic flexable membrain with 2 x one way valves acting as a pump!

Also there is a pipe running from the engine pulsing air to the membrain. I hope this makes some sort of sence.

Regards David

David Parrott
July 2009

You'll have to take the float bowl off from the bottom of the carburettor, followed by the float itself, held in by a thin shiny pin. The float will pull down the needle valve from its housing, and its here that the fault lies as its being held open by dirt. You may find this operation much easier if the complete carb is on the bench though....it all depends on how far you want to go.

John
July 2009