Mercury V8 250 User Manual

Fuel System
Section 7A - Fuel System
Table of Contents
Fuel System Specifications................................................7A-2
Fuel System Overview....................................................... 7A-2
Theory of Operation....................................................7A-2
Fuel System................................................................7A-2
Fuel Injector................................................................ 7A-2
In‑line Fuel Filter......................................................... 7A-3
V6 Fuel Flow Diagram................................................ 7A-4
V8 Fuel Flow Diagram................................................ 7A-6
Fuel Supply Module (FSM)................................................ 7A-7
Fuel Supply Module (FSM) Description...................... 7A-7
Fuel Pressure Regulator.............................................7A-8
Fuel Lift Pump.............................................................7A-8
High‑Pressure Fuel Pump.......................................... 7A-9
Fuel System
90-8M0146617 eng JULY 2018 © 2018 Mercury Marine Page 7A-1
7
A

Mercury V8 250 Specifications

General

Engine Type	V8
Horsepower	250 HP
Displacement	4.6L
Fuel Induction System	Electronic Fuel Injection (EFI)
Steering	Hydraulic Steering
Gear Ratio	1.75:1
Cylinders	8
Starting	Electric Start
Full Throttle RPM Range	5200-6000 RPM
Alternator Amp	85 amp
Shaft Length	25 in
Weight	527 lbs
Fuel Type	Unleaded 87 octane minimum