1. Engine Maintenance Chapter 10 Emergency Repairs Afloat

2. 2 Objectives 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

3. 3 Emergency Repairs Afloat If the Engine Stops If the Engine Stops do not panic do not panic the trouble is usually something simple the trouble is usually something simple Assess the Situation Assess the Situation safety is paramount concern safety is paramount concern when the boat is safe, turn to the engine problem when the boat is safe, turn to the engine problem

4. 4 Emergency Repairs Afloat Carry a small tool kit for emergency repairs Carry a small tool kit for emergency repairs Carry spare parts Carry spare parts Impellers Impellers Belts Belts

5. 5 Emergency Repairs Afloat 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?

6. 6 Emergency Repairs Afloat Knowing Symptoms Can Assist in: Knowing Symptoms Can Assist in: determining the cause of common problems determining the cause of common problems helping you suggest realistic repairs to a mechanic helping you suggest realistic repairs to a mechanic

7. 7 Gasoline Inboard Engines Gasoline is Highly Inflammable Gasoline is Highly Inflammable it is always a fire hazard it is always a fire hazard it requires constant care and close attention it requires constant care and close attention

8. 8 Gasoline Inboard Engines Fuel System Fuel System indications indications engine sputters and stops engine sputters and stops is fuel available to the engine? is fuel available to the engine? determine if fuel is reaching the manifold determine if fuel is reaching the manifold engines with carburetors engines with carburetors remove flame arrestor and look down into carburetor remove flame arrestor and look down into carburetor engines with fuel injectors engines with fuel injectors these systems require specialized test equipment and repair is beyond the scope of this course these systems require specialized test equipment and repair is beyond the scope of this course

9. 9 Gasoline Inboard Engines Troubleshooting the Fuel System Troubleshooting the Fuel System check the fuel pump check the fuel pump are there signs of leakage? are there signs of leakage? remove the oil dip stick and sniff for gasoline remove the oil dip stick and sniff for gasoline check the fuel filters check 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 supply check for water in the fuel supply

10. 10 Emergency Repairs Afloat Cooling System Cooling System indications indications engine gradually loses power and stops and temperature gauge reads hot engine gradually loses power and stops and temperature gauge reads hot check the drive belt check the drive belt if broken, only remedy is a new belt if broken, only remedy is a new belt Nylon belt may substitute Nylon belt may substitute sometimes, re-tensioning may work sometimes, re-tensioning may work

11. 11 Emergency Repairs Afloat Cooling System Cooling System a hot engine will usually restart after it has cooled down a hot engine will usually restart after it has cooled down check to see if cooling water is exiting the exhaust check to see if cooling water is exiting the exhaust if not, the raw water pump has failed or the intake is blocked if not, the raw water pump has failed or the intake is blocked if yes, either the thermostat or circulating pump has failed if yes, either the thermostat or circulating pump has failed

12. 12 Emergency Repairs Afloat Troubleshooting the Cooling System Troubleshooting the Cooling System thermostat failure thermostat failure solution: temporarily remove thermostat solution: temporarily remove thermostat if gasket is damaged, fashion one from cardboard if gasket is damaged, fashion one from cardboard circulating pump failure circulating pump failure indicator is leakage around shaft indicator is leakage around shaft may work sufficiently at low speed may work sufficiently at low speed seawater pump failure seawater pump failure first, check for blockage first, check for blockage remedy for failed pump: new impeller remedy for failed pump: new impeller

13. 13 Emergency Repairs Afloat It is Important to Maintain a Regular Lubrication Maintenance Schedule It is Important to Maintain a Regular Lubrication Maintenance Schedule check engine oil before start of each engine operation check engine oil before start of each engine operation check oil at every refueling check oil at every refueling change engine oil at regular intervals change engine oil at regular intervals recommended oil changes every 100 hours of operation or every three months recommended oil changes every 100 hours of operation or every three months refill with correct amount and type of oil refill with correct amount and type of oil replace the oil filter at every oil change replace the oil filter at every oil change

14. 14 Ignition System If engine stops suddenly, problem is probably the ignition system If engine stops suddenly, problem is probably the ignition system inspect distributor for cracks, corrosion, burning inspect distributor for cracks, corrosion, burning check coil wire for looseness check coil wire for looseness inspect breaker points for pitting, corrosion, burning inspect breaker points for pitting, corrosion, burning replace condenser if points are pitted or blackened replace condenser if points are pitted or blackened

15. 15 Ignition System Spark Plugs Spark Plugs inspect plug wires for looseness inspect plug wires for looseness inspect for cracked porcelain, burned electrodes, excessive electrode gap inspect for cracked porcelain, burned electrodes, excessive electrode gap

16. 16 Gasoline Outboard Engines Fuel System Problems Fuel System Problems rust in portable tanks – solution: replace tanks rust in portable tanks – solution: replace tanks infrequent use, gas left in carburetor – requires mechanic infrequent use, gas left in carburetor – requires mechanic if the engine sputters and quits, check the tank if the engine sputters and quits, check the tank is there fuel in the tank? is there fuel in the tank? is the vent valve open? is the vent valve open?

17. 17 Gasoline Outboard Engines Fuel System Problems Fuel System Problems fuel lines fuel lines check for cracks that can admit air check for cracks that can admit air squeeze the priming bulb to make sure there is fuel in the line and carburetor squeeze the priming bulb to make sure there is fuel in the line and carburetor water in fuel water in fuel check the filter for water check the filter for water change to a spare tank change to a spare tank

18. 18 Gasoline Outboard Engines Cooling System Problems Cooling System Problems check the cooling water overflow vent check the cooling water overflow vent is water coming out? is water coming out? if not: if not: shut down the engine shut down the engine check for intake blockage check for intake blockage if no water and intake is not blocked if no water and intake is not blocked impeller has failed impeller has failed replace the impeller replace the impeller

19. 19 Gasoline Outboard Engines Ignition System Problems Ignition System Problems if the engine stops instantaneously, ignition system is suspect if the engine stops instantaneously, ignition system is suspect check for loose wires throughout check for loose wires throughout check for high voltage at spark plug leads check for high voltage at spark plug leads Remove one plug wire and hold about ¼” from block, then crank the engine Remove one plug wire and hold about ¼” from block, then crank the engine Spark should jump from wire to metal Spark should jump from wire to metal If no spark, call a mechanic If no spark, call a mechanic Four stroke outboards should be treated the same as gasoline inboards Four stroke outboards should be treated the same as gasoline inboards

20. 20 Diesel Engine Fuel System Problems Fuel System Problems greatest problem with diesels greatest problem with diesels usually clogged filters usually clogged filters change/clean/drain filters change/clean/drain filters air trapped in system will keep engine from operating air trapped in system will keep engine from operating bleed air from the system when filters are changed bleed air from the system when filters are changed bacteria can grow in diesel fuel bacteria can grow in diesel fuel fuel tank must be purged and cleaned fuel tank must be purged and cleaned

21. 21 Troubleshooting Summary If the Engine Stops If the Engine Stops do not panic do not panic the trouble is usually something simple the trouble is usually something simple safety is paramount concern safety is paramount concern

22. 22 Troubleshooting Summary Remember How the Engine Sounded Remember How the Engine Sounded did it sputter-run-sputter-run-quit? did it sputter-run-sputter-run-quit? likely a fuel system problem likely a fuel system problem did it gradually lose power? did it gradually lose power? likely a cooling system problem likely a cooling system problem did it stop instantaneously? did it stop instantaneously? likely an ignition system problem likely an ignition system problem

23. 23 Troubleshooting Summary Best Advice: Check Before You Go Best Advice: Check Before You Go fuel level – is there enough to take you there and get you back? fuel level – is there enough to take you there and get you back? oil level oil level battery water battery water drive belt tension drive belt tension bilge water level bilge water level

24. 24 General Troubleshooting Methodology Check the Obvious Check the Obvious Check the Easy Check the Easy Check Systematically Check Systematically Make No Erratic Adjustments Make No Erratic Adjustments

25. 25 Remember… You should be able to identify problems and explain them to a mechanic