Engine Starts - Lehman SP90 Owner's Manual

LEHMAN DIESEL OWNER'S FAULT-FINDING GUIDE
Starter does not
crank engine
*Battery h n down
Battery cable or switch
**Air in fuel system
*Stop control engaged
Controls binding
Faulty injectors
ENGINE RUNS INTERMITTENTLY
-
*Air Leaking fuel system
Fuel (lift) pump diaphragm worn
Fuel filter (s) clogged
Sticking valves
Fuel Tank near empty
ROUGH IDLING
*Air in fuel system
*Idle adjustment set too low
Dirty or faulty injectors
Injector pipes loose, cracked
or broken
Incorrect injection timing
Restricted fuel filter
Faulty lift pump
Sticking valves
Broken valve springs
ENGINE MISFIRES
*Injector pipe loose, broken or
cracked
Injectors dirty
*Air leaking in fuel system
Sticking valve or rocker arm
Sticking piston rings
Engine needs top overhaul
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ENGINE STARTS

ENGINE KNOCKS
*Air in fuel system
Oil level (pressure) low, worn
bearings
Incorrect grade fuel oil
Incorrect injection timing
Faulty injector
Sticking valve or rocker arm
Piston slap
ENGINE NOT DELIVERING
FULL POWER
**Air fuel system
Engine overheated
Injection timing incorrect
Incorrect valve clearances
Dirty air cleaner(s)
Faulty injectors
Faulty injection pump
Stop control partly engaged
Sticking valves
Worn piston rings, or bores
Faulty lift pump
Restricted fuel filters
ENGINE OVERHEATS
*Insufficient water supply
Fresh water not circulating
*Battery partly run down
*Battery terminals loose,
Pump
**Air leak in fuel l i d
Fuel tank empty
*Stoppage in fuel line
Stoppage in fuel filter
Water in fuel system
Faulty lift pump
a) Loose or broken vee belt
b) Hoses clogged or collapsing while
running at high speed
c) Faulty thermostat
d) *Clogged heat exchanger
e) Clogged bleed hole in thermostat
Raw water flow insufficient
a) *Clogged sea water strainer
b) Water intake scoop damaged or lost
c) Sea cock closed
d) Water pump impeller damaged
e) *Heat exchanger or oil coolers
clogged.
Low crancase oil level
Incorrect injection timing
Engine needs top overhaul
ENGINE EXHAUST SMOKES
Fuel, poor grade (black smoke)
Crankcase overfilled (blue smoke)
Cold engine temperature (white or
lite blue)
*Propeller too large (black smoke)
Max. speed stop screw set too high
for load (black smoke)
Propeller too small (white smoke)
Incorrect injection timing
Faulty boost control unit
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Starter cranks
engine slowly
Injection pump
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