engine maintenance

Engine MaintenanceEngine Maintenance

Chapter 10Chapter 10

Emergency Repairs AfloatEmergency Repairs Afloat

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Objectives for the StudentObjectives for the Student

1.Have knowledge of some basic troubleshooting techniques for the fuel, cooling, and ignition systems of gasoline engines

2.Have knowledge of basic troubleshooting techniques for the fuel and cooling systems of diesel engines

3.Have knowledge of some simple repairs that can be made while afloat that will aid in getting the boat back to a safe harbor

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If the Engine StopsIf the Engine Stops do not panicdo not panic the trouble is usually something the trouble is usually something

simplesimple Assess the SituationAssess the Situation

safety is paramount concernsafety is paramount concern when the boat is safe, turn to when the boat is safe, turn to

the engine problemthe engine problem

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Carry a small tool kit for Carry a small tool kit for emergency repairsemergency repairs

Carry spare partsCarry spare parts ImpellersImpellers BeltsBelts

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Did it Sputter-Run-Sputter-Run-Quit?Did it Sputter-Run-Sputter-Run-Quit? Did it Gradually Lose Power?Did it Gradually Lose Power? Did it Stop Instantaneously?Did it Stop Instantaneously?

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Knowing Symptoms Can Knowing Symptoms Can Assist in:Assist in: determining the cause of determining the cause of

common problemscommon problems helping you suggest realistic helping you suggest realistic

repairs to a mechanicrepairs to a mechanic

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Gasoline Inboard EnginesGasoline Inboard Engines

Gasoline is Highly InflammableGasoline is Highly Inflammable it is always a fire hazardit is always a fire hazard it requires constant care and close it requires constant care and close

attentionattention

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Fuel SystemFuel System indicationsindications

engine sputters and stopsengine sputters and stops is fuel available to the engine?is fuel available to the engine? determine if fuel is reaching the manifolddetermine if fuel is reaching the manifold engines with carburetorsengines with carburetors

remove flame arrestor and look down into remove flame arrestor and look down into carburetorcarburetor

engines with fuel injectorsengines with fuel injectors these systems require specialized test these systems require specialized test

equipment and repair is beyond the scope of equipment and repair is beyond the scope of this coursethis course

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Troubleshooting the Fuel SystemTroubleshooting the Fuel System check the fuel pumpcheck the fuel pump

are there signs of leakage?are there signs of leakage? remove the oil dip stick and sniff for remove the oil dip stick and sniff for

gasolinegasoline check the fuel filterscheck the fuel filters

is the filter clogged?is the filter clogged? is there water in the filter?is there water in the filter?

check for water in the fuel supplycheck for water in the fuel supply

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Cooling SystemCooling System indicationsindications

engine gradually loses power and engine gradually loses power and stops and temperature gauge stops and temperature gauge reads hotreads hot

check the drive beltcheck the drive belt if broken, only remedy is a new beltif broken, only remedy is a new belt Nylon belt may substituteNylon belt may substitute sometimes, re-tensioning may worksometimes, re-tensioning may work

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Cooling SystemCooling System a hot engine will usually restart a hot engine will usually restart

after it has cooled downafter it has cooled down check to see if cooling water is check to see if cooling water is

exiting the exhaustexiting the exhaust if not, the raw water pump has if not, the raw water pump has

failed or the intake is blockedfailed or the intake is blocked if yes, either the thermostat or if yes, either the thermostat or

circulating pump has failedcirculating pump has failed

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Troubleshooting the Cooling SystemTroubleshooting the Cooling System thermostat failurethermostat failure

solution: temporarily remove thermostatsolution: temporarily remove thermostat if gasket is damaged, fashion one from if gasket is damaged, fashion one from

cardboardcardboard circulating pump failurecirculating pump failure

indicator is leakage around shaftindicator is leakage around shaft may work sufficiently at low speedmay work sufficiently at low speed

seawater pump failureseawater pump failure first, check for blockagefirst, check for blockage remedy for failed pump: new impellerremedy for failed pump: new impeller

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It is Important to Maintain a It is Important to Maintain a Regular Lubrication Maintenance Regular Lubrication Maintenance ScheduleSchedule check engine oil before start of each check engine oil before start of each

engine operationengine operation check oil at every refuelingcheck oil at every refueling change engine oil at regular intervalschange engine oil at regular intervals recommended oil changes every 100 recommended oil changes every 100

hours of operation or every three monthshours of operation or every three months refill with correct amount and type of oilrefill with correct amount and type of oil replace the oil filter at every oil changereplace the oil filter at every oil change

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Ignition SystemIgnition System

If engine stops suddenly, problem If engine stops suddenly, problem is probably the ignition systemis probably the ignition system inspect distributor for cracks, inspect distributor for cracks,

corrosion, burningcorrosion, burning check coil wire for loosenesscheck coil wire for looseness inspect breaker points for pitting, inspect breaker points for pitting,

corrosion, burningcorrosion, burning replace condenser if points are replace condenser if points are

pitted or blackenedpitted or blackened

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Ignition SystemIgnition System

Spark PlugsSpark Plugs inspect plug wires for loosenessinspect plug wires for looseness inspect for cracked porcelain, burned inspect for cracked porcelain, burned

electrodes, excessive electrode gapelectrodes, excessive electrode gap

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Gasoline Outboard EnginesGasoline Outboard Engines

Fuel System ProblemsFuel System Problems rust in portable tanks – solution: rust in portable tanks – solution:

replace tanksreplace tanks infrequent use, gas left in infrequent use, gas left in

carburetor – requires mechaniccarburetor – requires mechanic if the engine sputters and quits, if the engine sputters and quits,

check the tankcheck the tank is there fuel in the tank?is there fuel in the tank? is the vent valve open?is the vent valve open?

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Fuel System ProblemsFuel System Problems fuel linesfuel lines

check for cracks that can admit aircheck for cracks that can admit air squeeze the priming bulb to make squeeze the priming bulb to make

sure there is fuel in the line and sure there is fuel in the line and carburetorcarburetor

water in fuelwater in fuel check the filter for watercheck the filter for water change to a spare tankchange to a spare tank

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Cooling System ProblemsCooling System Problems check the cooling water overflow check the cooling water overflow

ventvent is water coming out?is water coming out? if not:if not:

shut down the engineshut down the engine check for intake blockagecheck for intake blockage

if no water and intake is not blockedif no water and intake is not blocked impeller has failedimpeller has failed replace the impellerreplace the impeller

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Ignition System ProblemsIgnition System Problems if the engine stops instantaneously, if the engine stops instantaneously,

ignition system is suspectignition system is suspect check for loose wires throughoutcheck for loose wires throughout check for high voltage at spark plug leadscheck for high voltage at spark plug leads

Remove one plug wire and hold about ¼” Remove one plug wire and hold about ¼” from block, then crank the enginefrom block, then crank the engine

Spark should jump from wire to metalSpark should jump from wire to metal If no spark, call a mechanicIf no spark, call a mechanic Four stroke outboards should be treated the Four stroke outboards should be treated the

same as gasoline inboardssame as gasoline inboards

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Diesel EngineDiesel Engine

Fuel System ProblemsFuel System Problems greatest problem with dieselsgreatest problem with diesels usually clogged filtersusually clogged filters

change/clean/drain filterschange/clean/drain filters air trapped in system will keep engine air trapped in system will keep engine

from operatingfrom operating bleed air from the system when filters are bleed air from the system when filters are

changedchanged bacteria can grow in diesel fuelbacteria can grow in diesel fuel

fuel tank must be purged and cleanedfuel tank must be purged and cleaned

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Troubleshooting SummaryTroubleshooting Summary

If the Engine StopsIf the Engine Stops do not panicdo not panic the trouble is usually something the trouble is usually something

simplesimple safety is paramount concernsafety is paramount concern

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Remember How the Engine Remember How the Engine SoundedSounded did it sputter-run-sputter-run-quit?did it sputter-run-sputter-run-quit?

likely a fuel system problemlikely a fuel system problem did it gradually lose power?did it gradually lose power?

likely a cooling system problemlikely a cooling system problem did it stop instantaneously?did it stop instantaneously?

likely an ignition system problemlikely an ignition system problem

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Best Advice: Check Before You Best Advice: Check Before You GoGo fuel level – is there enough to fuel level – is there enough to

take you there and get you back?take you there and get you back? oil leveloil level battery waterbattery water drive belt tensiondrive belt tension bilge water levelbilge water level

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General Troubleshooting General Troubleshooting MethodologyMethodology

Check the ObviousCheck the Obvious Check the EasyCheck the Easy Check SystematicallyCheck Systematically Make No Erratic AdjustmentsMake No Erratic Adjustments

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Remember…Remember…

You should be able to You should be able to identify problems and identify problems and explain them to a mechanicexplain them to a mechanic

engine maintenance

Documents

realistic repairs

simple repairs

refuelingchange engine

engine operationcheck

fuel systemcheck

fuel pumpare

engine stopsdo

fuel filtersis