Installation manual

4-29

90-898305

Tracker Valve (V6 Models Only)

• Tracker valve designed to maintain 10 psi differential between the fuel

rails when air or fuel pressure suddenly rises (air compressor pulses or

fuel injectors opening & closing)

• Contains a spring (on the ‘air’ side) & a diaphragm

• When engine isn’t running, spring positions diaphragm against seat

• When the engine is running, fuel pressure compresses spring and

diaphragm moves slightly away from seat, to a ‘neutral’ position

• Pressure on both sides of diaphragm is equal

• Note: to prevent excessive seat wear, the tracker valve is calibrated to

allow the diaphragm to be slightly away from the seat during normal

operation.

• Any air or fuel pressure ‘spikes’ on either side of the diaphragm will

transfer this pressure increase to the other side of the diaphragm

• Both sides (air & fuel) will have a momentary increase in pressure so that

the 10 psi difference can be maintained

• If pressure rises inside fuel passage, the diaphragm will flex into the air

passage, causing a proportionate increase in air pressure

• If pressure rises in the air passage, the diaphragm flexes into the fuel

passage, increasing the fuel pressure proportionately

SECTIONAL VIEW TRACKER VALVE

a - Spring

b - Air passage

c - Fuel passage

d - Diaphragm

Notes

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