Fuel Pump

[DOOmsman]

BASIC FUEL SYSTEMS
Almost all gas golf carts have fuel pumps. The pumps operate off of a tube that is tapped into the crankcase of the engine. These lines sometimes have tees in them that go to the valve cover, but for now we will not concern ourselves with that line. The line from the crankcase pulses from the piston going up and down creating vacuum and pressure.
The fuel pump has three chambers; an inlet; an outlet and a pulse. The pulse chamber flexes a diaphragm that pumps the fuel in the other chambers. The fuel in the inlet and outlet is moved through a pair of small flap style valves.
Weak or no fuel delivery can be caused by
1-broken or stretched diaphragm
2-gumed up pulse chamber, or valve
3-pieces of junk or dirt in the valves
4-old stiff valves and or diaphragm
5-leaks to the outside of the pump, sometimes gas will drip sometimes not
6-non pump related issues
A plugged filter
B air leaks in the fuel lines
C carb inlet needle and valve plugged or stuck
D bad crankcase seals on two stroke engines
E missing oil filler top
There are arrows on the pump showing in and out and the pulse line

The pulse chamber is the outer most, note dings on the screws I use vice grips to break them loose and always use never seize when reinstalling them

If you don't have a new gasket be very careful when taking apart

The inlet and outlet chambers

The disc valves, inspect for debris under the little discs

The pulse chamber may be full of white gunk (I used sawdust and olive oil)

clean the chamber and pulse tube and line

Be sure to line it all up (a scratched line will help) when assembling
I like a inline filter with a shutoff valve and I use screw clamps instead of the wire kind



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[Quadmaster]

This should be a Sticky. Great job dooms

[TheNewGuy]

Thanks Dooms

[scottyb]

Looks great Dooms What cart is that off of?

[DOOmsman]

Pump is off HAHA my Yamaha G8.

[Flintrock]

Thanks DoomS. That is great information and a very nice presentation. Don't need now but will someday so I know where to go. Keep that sawdust and olive oil out of your gas tank! (JK).

[rschap1]

Thanks for that too! Neighbors G16A has a different (square) pump, but some good stuff for anyone!

[dogpile]

The g16 square pump is made by the same company, looks a bit different on the inside but works generally the same exact way...

Doom,
Ive heard of a rice burners but seriously looks like rice in your fuel pump!!

[GarMaster]

Where do you get the hose clamps? I like em....

[hilljack]

Thanks Dooms. On my CC at one time my fuel line had dropped below the engine and driving around oil would bounce into the line and gave me trouble.