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115 hp Merc Optimax takes 6 goes to start when cold

  • 30-05-2012 10:54AM
    #1
    Ned_led16
    Registered Users, Registered Users 2 Posts: 329 ✭✭


    Theres a clicking noise and the volts reading goes up and down rapid within a second!

    Any ideas? just wonder as we changed the fuse board and fuses -whats thestandard fuse is for a 115 hp ignition fuse?

    Any help would be much appreciated dont really wanna bring it to the mechanic staright away without checking online b4!

    After i finnished up yesterday i stopped and started it fine 5 times. But it took about 6 goes when on the mooring at the start of the session???

    Plenty of oil in it - the gearbox oil was low enough about 40 hrs ago!


Comments

  • #2
    breghall
    Registered Users, Registered Users 2 Posts: 605 ✭✭✭breghall


    check all your wiring connections at the battery and to the engine to make sure they are tight.That i'd be there first place I'd try especially if i hear clicking.


  • #3
    fergal.b
    Moderators, Motoring & Transport Moderators, Sports Moderators, Paid Member Posts: 6,386 Mod ✭✭✭✭fergal.b


    The clicking noise could be the solenoid or the electric fuel pump, do you have the right battery, the optimax needs at least a 1,000 MCA "marine cranking amps" there are several fuses on these engines and the main one in your box should be 15-20 amp check your work shop manual to be sure. also is your fuel new if the fuel has been sitting since last year without stabilizer it can be harder to start.
    One thing you could try is prim the engine by pumping the bulb till it's hard then turn on the ignition "don't start" and move the throttle lever forward and back 3-4 times with the cowling removed you should be able to hear the pump clicking when it stops the engine is then primed and ready to go.



    .


  • #4
    Ned_led16
    Registered Users, Registered Users 2 Posts: 329 ✭✭Ned_led16


    ok figured it out:

    The connections to the battery were a little corroded and dirty - so i sanded the connections down and put them back on - now she starts on the button - that priming it might have been a bad idea cause petrol was getting in - it was merely the battery!

    So 1 thing leads to another - a lad at the beach was showing me the button under the throttle which engages a clutch and allows you to rev the engine in neutral.... he showed me the theory - in practice it didnt work because - the battery connections needed tidying up!

    But now for some reason in njeutral the engine ticks over a bit higher than normal - i wonder is that something to do with priming it so much when it wasnt needed or if its because of that button under the clutch.... as i say prob better to ask online b4 calling the doc out!


  • #5
    fergal.b
    Moderators, Motoring & Transport Moderators, Sports Moderators, Paid Member Posts: 6,386 Mod ✭✭✭✭fergal.b


    What ever you primed in will be burned up with in a minute and the fuel line pressure returned to normal it won't cause the engine to hold higher revs.
    Some controls have a neutral rev leaver that lies flat across the top make sure it is fully down.


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