Unit Pump

1. Product Information

An EM (electromagnetic) plunger is a small precision steel part inside a solenoid-type diesel injector.
It moves up and down when the injector’s electromagnetic coil is energized.

What does it do?

Its job is to control fuel injection timing and quantity.

When the ECU sends a signal

1. The solenoid coil is energized
2. A magnetic field pulls the EM plunger upward
3. This opens the control valve
4. Rail pressure lifts the nozzle needle
5. Fuel is injected into the cylinder

When the power is cut

The plunger returns (spring + fuel pressure)
The control valve closes
Injection stops

2. Product Model List

No.	Stamp	Model	Flange	Application	Picture
1	54	60-503-54	thin	High Pressure Section L 245 Motorpal 382 Unit Pump Model 60-503-54
2	57	60-503-59	thin	Unit Pump Model 60-503-59
3	49	60-503-49	thin	Unit Pump Model 60-503-49
4	68/82	60-503-82	thick	High Pressure Section D 260 Motorpal 355 EM10PI-68 KA382 for Four-cylinder Engine D2455S2 Engine, Plunger φ10mm Flat stamp 68/53 Unit Pump Model 60503-82
5	89	60-503-89	thick	Unit Pump Model 60-503-89
6	71	60-403‑71	thick	EM10PI-71 PY389 for Six-cylinder Engine D260 Engine,Plunger φ10mm Flat stamp Unit Pump Model 60-403-71