B & S 3.5

beatsal

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My lawn mower engine just won't start. Bought a new diaphragm and gasket for the carb, no luck. Iput the gasket on and then the diaphragm, not sure if that is correct or should it be reverse?
 

Scrubcadet10

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Please provide the engine model numbers, usually stamped above the spark plug on that engine...
have you checked for spark? get some starting fluid, parts cleaner or gasoline, remove the air filter and pour about 1 tablespoon/slightly less, into the intake and try to start it...
 

beatsal

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It says B & S Classic, no model #. It starts for a second if I do as you said i.e. pour gas into intake. I can send a pic if it helps
 

Rivets

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Engine numbers are located on the blower housing, just above the spark plug.
 

beatsal

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Thanks but being an old one could not find model so will have to try any ideas you have
 

Rivets

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Did you look on the side of the blower housing? I’ve worked hundreds of older Briggs engines and unless someone has taken a grinder to remove them. Have you taken a green scrubby from your wife’s cleaning supplies and made sure that both areas are clean? If it is an old Briggs I can’t believe they are gone.
 

dougand3

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Carb on tank....the gasket goes on bottom of plastic carb first, then the diaphragm. The diaphragm is against the metal tank.
 

HandyBoyNZ2

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Try this file.
 

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beatsal

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Carb on tank....the gasket goes on bottom of plastic carb first, then the diaphragm. The diaphragm is against the metal tank.
Thanks, it worked! Just wondering - by pushing the rubber priming bulb, how is the fuel sprayed i.e. push bulb - pressure reduces, gas from tank gets sprayed. Intuitively, by pressing the bulb, shouldn't the pressure incresae momentarily?
 
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