Cub Cadet service manual M48 Tank, Electronic Control Module Fuel pump, Figure

M48 Tank

10.5.The return lines each lead back to the tank from a tee fitting just beneath the tee fitting for the fuel feed lines. The return fuel comes from the fuel pressure regulator.

NOTE: If one branch of the return line becomes crushed, kinked, or blocked, a disproportionate amount of fuel will return the the opposite tank.

•If one fuel tank consistently empties before the other, check the return lines.

•If this situation should occur with full tanks, an over-flow will result.

10.6.The fuel feed line leads from the tanks and tee down to a high pressure fuel pump located beneath the ECM. See Figure 10.6.

Electronic

Control

Module

Fuel pump

Figure 10.6

CAUTION: Before disconnecting any fuel line:

•Allow the engine to cool, and be sure the area is clear of any potential fire hazards, and has ade- quate ventilation.

•Have a catch pan handy to contain any spillage

•Relieve pressure from the any fuel lines between the fuel pump and the fuel rail.

NOTE: The fuel pump uses the fuel as a coolant. If the engine runs out of fuel, turn the key off immediately. Running dry will damage the pump.

NOTE: The fuel pump will run briefly each time the key switch is turned on. This pressurizes the system. If fuel pressure is absent, and the fuel pump cannot be heard when the key switch is turned on, the fuel pump may not be getting electricity. Check for power before condemning the fuel pump.

NOTE: The fuel pump is protected by an internal 60∝ filter.

10.7.The pump sends pressurized fuel to the fuel pressure regulator. The regulator maintains a constant down-stream pressure of between 36 and 42 PSI. See Figure 10.7.

Fuel pump

Fuel pressure regulator

Figure 10.7

NOTE: High pressure fuel lines (SAE R9 rating) and Oetiker style hose clamps must be used between the fuel pump, pressure regulator, fuel filter, and fuel injector rail.

CAUTION: Substitution of fuel system compo- nents that are not capable of handling the pres- sure generated by this fuel system will lead to rapid failure of those components. Component failure (hose, clamps, filter, etc...) in the high pressure portion of the system poses a signifi- cant fire hazard.

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