Table of Contents
Page
Page
Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1C-1
Used Spark Plug Analysis . . . . . . . . . . . . . . . . . 1C-2
Spark Plug Analysis . . . . . . . . . . . . . . . . . . . . . . 1C-2
Normal Condition . . . . . . . . . . . . . . . . . . . . . . 1C-2
Chipped Insulator . . . . . . . . . . . . . . . . . . . . . . 1C-2
Wet Fouling (Oil Deposits) . . . . . . . . . . . . . . 1C-2
Cold Fouling . . . . . . . . . . . . . . . . . . . . . . . . . . 1C-3
Overheating . . . . . . . . . . . . . . . . . . . . . . . . . . 1C-3
High Speed Glazing . . . . . . . . . . . . . . . . . . . . 1C-3
Scavenger Deposits . . . . . . . . . . . . . . . . . . . 1C-3
Pre-Ignition Damage . . . . . . . . . . . . . . . . . . . 1C-4
Reversed Coil Polarity . . . . . . . . . . . . . . . . . . 1C-4
Splashed Deposits . . . . . . . . . . . . . . . . . . . . . 1C-4
Mechanical Damage . . . . . . . . . . . . . . . . . . . 1C-4
Poor Boat Performance and/or Poor
Maneuverability . . . . . . . . . . . . . . . . . . . . . . . . . 1C-5
Improper Full Throttle Engine RPM . . . . . . . . . 1C-6
RPM Too High . . . . . . . . . . . . . . . . . . . . . . . . 1C-6
RPM Too Low . . . . . . . . . . . . . . . . . . . . . . . . . 1C-6
Engine Cranks Over but Will Not Start
or Starts Hard . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1C-7
Important Information . . . . . . . . . . . . . . . . . . 1C-7
Testing Thunderbolt IV HEI System . . . . . . 1C-8
Testing Thunderbolt V Ignition System . . . . 1C-9
Fuel System Rich . . . . . . . . . . . . . . . . . . . . . 1C-10
Fuel System Lean . . . . . . . . . . . . . . . . . . . . 1C-10
Miscellaneous . . . . . . . . . . . . . . . . . . . . . . . . 1C-10
Engine Will Not Crank Over . . . . . . . . . . . . . . . 1C-11
Charging System Inoperative . . . . . . . . . . . . . 1C-11
Noisy Alternator . . . . . . . . . . . . . . . . . . . . . . 1C-11
Instrumentation Malfunction . . . . . . . . . . . . . . 1C-12
Radio Noise . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1C-12
Poor Fuel Economy . . . . . . . . . . . . . . . . . . . . . 1C-13
Carburetor Malfunctions . . . . . . . . . . . . . . . . . . 1C-14
Engine Runs Poorly at Idle . . . . . . . . . . . . . . . 1C-15
Engine Runs Poorly At High RPM . . . . . . . . . 1C-16
Engine Acceleration Is Poor . . . . . . . . . . . . . . 1C-17
Troubleshooting with Vacuum Gauge . . . . . . 1C-17
Engine Noise . . . . . . . . . . . . . . . . . . . . . . . . . . . 1C-18
Important Information . . . . . . . . . . . . . . . . . 1C-18
Valve Cover Area . . . . . . . . . . . . . . . . . . . . . 1C-18
Cylinder Area . . . . . . . . . . . . . . . . . . . . . . . . 1C-19
Camshaft Area . . . . . . . . . . . . . . . . . . . . . . . 1C-19
Crankshaft Area . . . . . . . . . . . . . . . . . . . . . . 1C-20
Miscellaneous . . . . . . . . . . . . . . . . . . . . . . . . 1C-21
Oil Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1C-22
Low Oil Pressure . . . . . . . . . . . . . . . . . . . . . 1C-23
High Oil Pressure . . . . . . . . . . . . . . . . . . . . . 1C-23
Excessive Oil Consumption . . . . . . . . . . . . . . . 1C-24
Water In Engine . . . . . . . . . . . . . . . . . . . . . . . . . 1C-25
Important Information . . . . . . . . . . . . . . . . . 1C-25
Water on Top of Pistons . . . . . . . . . . . . . . . 1C-25
Water in Crankcase Oil . . . . . . . . . . . . . . . . 1C-26
Engine Overheats (Mechanical) . . . . . . . . . . . 1C-26
Engine Overheats (Cooling System) . . . . . . . 1C-27
Insufficient Water Flow from Belt Driven
Seawater Pickup Pump . . . . . . . . . . . . . . . 1C-28
Power Steering . . . . . . . . . . . . . . . . . . . . . . . . . 1C-29
Poor, Erratic, or No Assist . . . . . . . . . . . . . 1C-29
Noisy Pump . . . . . . . . . . . . . . . . . . . . . . . . . . 1C-30
Fluid Leaks . . . . . . . . . . . . . . . . . . . . . . . . . . 1C-30
Troubleshooting Silent Choice Exhaust
Silencer System . . . . . . . . . . . . . . . . . . . . . . . . 1C-31
Index
1C-0 - TROUBLESHOOTING
90-823224--2 796
| Categories | Mercury MerCruiser Manuals |
|---|---|
| Tags | Mercury MerCruiser 454 CID, Mercury MerCruiser 502 CID |
| Model Year | 1993, 1994, 1995, 1996, 1997 |
| Download File |
|
| Document File Type | |
| Copyright | Attribution Non-commercial |
(4 votes, average: 4.5 out of 5)
Marine readers have rated 1993 1997 Mercury-MerCruiser GM V8 454 CID 7.4L and 502 CID 8.2L Marine Engines Service Manual Number 16 4.5 out of 5.0 based on 4 product reviews. Hugely helpful service manual! Perfect. Thank you!
Manuals are all Important for Technician
This book is invaluable if you do your own repairs. Great book.
Could not find a copy until a search brought me here.
Excellent print.
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