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Curtis B.
Curtis B., Technician
Category: Small Engine
Satisfied Customers: 26026
Experience:  have worked on and around most engine models for 35 yrs./Polaris ATV expert
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Deere lawn tractor D120 was being used to mow grass and the

Customer Question

John Deere lawn tractor D120 was being used to mow grass and the engine started to get weak losing rpm's and then quit. I can start it but it dies. I can start it and kick the choke and kept it running enough to get it back in the garage. Took the fuel filter off and blew through it - seems fine. What's the round black plastic thing the fuel line goes to between the filter and carb??
JA: Do you have fuel in the tank? If so, is the shut-off valve open and the fuel clean?
Customer: Yes
JA: Do you plan on doing the work yourself?
Customer: yep
JA: Anything else we should know to help you best?
Customer: I don't know anything more yet.
Submitted: 3 months ago.
Category: Small Engine
Expert:  Curtis B. replied 3 months ago.

Single cylinder Briggs engine, The round plastic piece is the fuel pump. A pulse pump that uses the piston pulses of the cylinder to move a diaphragm in the fule pump to pump the fuel fromtank to the carburetor. It has to pickup the fuel from the top of the tank, through a suction tube. If there is a break in the vacuum before the pump, it will not suck.

Expert:  Curtis B. replied 3 months ago.

If you tank the fuel line off after the pump or at the carburetor end, do you have fuel squirting when cranking? If you d , the fuel pump and supply are ok. That would leave the electric fuel solenoid in the carburetor base as a possible trouble spot. It has to have 12 volts to it , as link as the key is on

Expert:  Curtis B. replied 3 months ago.

as long as the key is on

Expert:  Curtis B. replied 3 months ago.


Expert:  Curtis B. replied 2 months ago.

I see question is still open, did you find the problem?