Yanmar 4BY - Engine Piping Diagrams

GENERAL SERVICE INFORMATION
BY Service Manual
3-7
Engine Piping Diagrams
ENGINE PIPING DIAGRAMS
Fuel Flow
Figure 3-5
Note: Typical 4BY engine shown. 6BY is similar.
1 – Fuel from Tank
2 – Fuel Filter / Water Separator
3 – Fuel Feed Pump
4 – Fine Fuel Filter
5 – Inlet Fuel Temperature Sensor
6 – High-Pressure Fuel Pump
7 – High-Pressure Fuel Supply Line
8 – Common Fuel Rail
9 – Fuel Injection Line (1 each injector)
10 – Fuel Injector (1 each cylinder)
11 – Fuel Injector Return Fuel Hose
12 – Common Rail Return Fuel Line
13–Tee
14 – Fuel Return from High-Pressure Pump
15 – Return Fuel to Fuel Tank
16 – Fuel Pressure Sensor
17 – Fuel Pressure Regulator (ECU-Controlled)
18 – High-Pressure Fuel Flow Regulator
(ECU-Controlled)
0003634
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(2)
(14)
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(18)
(5)
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(11)
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(1)
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