B&S lawn mower 650 will not start without starting fluid.

Petriw

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  • / B&S lawn mower 650 will not start without starting fluid.
650 engine will not start without starting fluid. Once started it will continue to run smooth and normal. Has new spark plug and air filter.
Dirty carb? Primer not working?
 

Scrubcadet10

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  • / B&S lawn mower 650 will not start without starting fluid.
need the model number of the engine.
if its an older L head engine it will be stamped around thr spark plug area or on a flap above the muffler. Now if its a newer OHV engine, that's on a sticker... and no telling if the sticker is still on the front of the air filter or not.
 

hlw49

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  • / B&S lawn mower 650 will not start without starting fluid.
Primer on the air box if it is the air box is warped and will need to be replaced
 

Petriw

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  • / B&S lawn mower 650 will not start without starting fluid.
need the model number of the engine.
if its an older L head engine it will be stamped around thr spark plug area or on a flap above the muffler. Now if its a newer OHV engine, that's on a sticker... and no telling if the sticker is still on the front of the air filter or not.
124T02 0231 B1
 

StarTech

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  • / B&S lawn mower 650 will not start without starting fluid.
These flat prime base tend to warp leading to the primer not working. When putting a primer gasket lightly torque the screws and then remove the primer base and look at the gasket. It show areas of non contact. When I see this this I make a wedge gasket using two gaskets glue together and cut into a wedge shape to add more pressure to areas needing more contact.

Also this warpage can be cause by over tightening the retaining screws.
 

Petriw

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  • / B&S lawn mower 650 will not start without starting fluid.
Primer on the air box if it is the air box is warped and will need to be replaced
Does not appear warped. Replaced Air box to carb gasket, primer bulb. Cleaned
Primer on the air box if it is the air box is warped and will need to be replaced
Mower starts and runs on 3-5 pushes of primer bulb. Also cleaned carb, and flushed all passages
 
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