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Troubleshooting

Details

• UBUCid=Troubleshoot
• 
• Category = Troubleshooting
• Optionality =
• Because = Actions to take if the boat engines will not start
• Estimated Cost =
• Frequency in Months =
• Level = hard
• Estimated time in hrs =

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Instructions

                    The engines should start easily, but they can be tempramental, if after following the proper start procedure for the current ambient temperature see  the engine doesn't start
                 this procedure documents a couple of possibilities and steps to try

                    If the engine does not start, consider whether the engine might be flooded with too much fuel.  A symptom of this is wet fuel on the .  This can happen if 
                 the choke is not properly used or if the mixture is set too rich or if the engine was not previously run dry and has been stored on its side allowing 
                  fuel to drain from the carb into the cylinders.  Too much fuel prevents starting for 2 reasons, firstly the air fuel mixture is too rich to ignite, secondly liquid fuel on the spark plugs fouls the plug preventing a spark.  A flooded engine will not start and the fuel must be cleared.  One strategy is to wait wait for 10 mins for it to evapourate   but this takes time and will not work for a heavily flooded engine.  Another strategy is to try and remove the fuel by disconnectting the fuel line from the engine and 
                  open the airway by setting full throttle and no choke, switch the electrics off and and pull it over 10-20 times to clear the fuel before trying to restart.  Once it does start keep it running at fast idle and don't load the engine until it is able to idle properly.  If misuse of choke caused the problem berate/educate the boat handler.


                    To check fuel is actually getting to the engine disconnect the fuel line and whilst depressing the connector valve 
                 pump fuel through the line back into the fuel tank confirming that the fuel line is not blocked.  Reconnect fuel line and prime bulb and inspect for any leaks in the fuel line, connectors,  and tank connectors where air can enter the system.
                 An air leak should not prevent the engine starting if the priming bulb has got fuel to the engine but it will starve the engine of fuel after it has started.

                    In turn disconnect remove and inspect each .  Using the  the  check the spark gap is between 0.9 to 1.0mm.
                 Inspect the sparkplug against .  If the plug is oiled or fouled note and replace with spares or at least clean and dry with .  Replace the spark plugs
                 connect the  pull the engine over and check that the spark tester is lighting.  If it isn't then inspect the .  If it looks to be 
                 in poor condition these are replaced by unscrewing from the HT lead.  If the spark is not sparking then the electrical system needs to be investigated.  On our engines
                 the kill switch works by grounding the ignition circuit.  When the  is removed the  makes a connnection grounding the ignition circuit, therefore the engine 
                 should work with  disconnected and if it then starts the switch is dodgy.  Tohatsu outboards are also known for grounding problems so check that the
                        is firmly connected

                    Carb clogging is a frequent cause of problems on our boats because of the commposition of modern fuel see videos logged under .  This makes it important to ensure fuel is drained from the system each day and its worth 
                    adding a  to the fuel.  Take the  and spray the inside of the carb and also 
                 through the  and  at the top of the carb and attempt restarting.  If that doesn't work
                 turn the  gently inwards until it reaches its end stop counting the turns then withdraw and spray 
                 into the hole.  Then replace the  exactly where it was before by replacing it and turning it into its end stop and then counting back from that end stop.  Attempt restarting

                    If the engine still will not start consider water in the fuel system.  Unscrew and check for water and debris in the  and
                 then .  Clean the  with the  and 

                    If, having followed the previous steps the engine still does not start then the boat should be towed back and the problem fully 
                 investigated.  With 2 identical engines insight can be gained from comparing the working engine with the broken engine.  But a problem with no electrical cause is 
                 most likely to be a carb problem and as a matter of course the carb should be dismantled and carefully cleaned with  and compressed air from .

                    Once the engine is finally restarted, the mixture and idle settings should be checked especially if the sparks plugs appear to indiciate a rich or lean mixture.  The engine should be run long enough to bring it up to temprature.  Then connect the  and adjust the  in order to get 950 RPM in neutral at idle.
                 With the idle set adjust the  in order to find that setting with maximum RPM.  Once the maximum position is found should be set 1/8th of a turn out from that maximum position.  Reset the  to 950 RPM in neutral/850 RPM idling in gear