Trouble starting Mercruiser 4.3 MPI V6
Hi, I have been having trouble starting my 4.3 MPI Mercruiser that is installed in my 2007 Trophy. I have had it in and out of the mechanics and they can't figure out what is wrong so I thought someone on here may have a suggestion...
50% of the time it starts fine regardless of whether it is hot or cold but the other 50% of the time it just cranks over and over until I pump the throttle... The mechanics thought it maybe the IAC valve so we tried another one- still the same....
While cranking it over the voltage to the Lowrance GPS drops to a point where it just cuts out and has to be restarted. I thought maybe the batteries weren't up to the job so I replaced them with larger cells that are now 750 CCA that I charge after every trip just to be sure but still the problem persists.
I now leave the motor running all day rather than this rigmarole of having to restart the GPS after every drift so the hours are clocking up and I would like to sell the boat soon so I would really like to sort this out so as not to pass it on to the next owner....
All suggestions are very welcome.... Thanks in advance.....
Winta.....
NEVER PUSH YOUR GRANNY WHEN SHE'S SHAVING
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dodgy
Posts: 4569
Date Joined: 01/02/10
Does sound like the fuel
Does sound like the fuel draining back to the tank and has to be cranked back up again. A leak in the fuel system somewhere.
Does anyone know where the love of god goes, when the waves turn the minutes to hours?
carnarvonite
Posts: 8643
Date Joined: 24/07/07
Starter motor
I'd be checking the brushes on your starter motor if its taking that much power to spin it over. No doubt Kempy, one of the sites members will have an idea as well
Vinesh87
Posts: 2751
Date Joined: 02/04/11
My 4.3 kills 1 of my
My 4.3 kills 1 of my raymarine 50% of the time.have 2 900cca batteries but it starts perfectly every time. Only drops to 11v very momentarily just has a crappy tolerance.
Will be watching this thread closely,good luck!
tim-o
Posts: 4657
Date Joined: 24/05/11
Voltage drop whilst cranking
Voltage drop whilst cranking is normal and the HDS just has a low voltage shut off Id say. A dual batt set up with one as a cranking only batt and the other for accessories will solve this, like a 4x4 set up. As for not starting, give it some carb cleaner in the throttle body, if she goes, you have a fuel prob, low pressure or inj pulse. No go with that can indicate you have too much too fuel to begin with or an ignition issue. Pull the plugs when it happens, they tell the story, may be fouling up, should be platinum but check they are the right ones fitted, but you may have an over fueling issue. If they look good and are wet check for spark, but will be hard if they have coil packs on the plugs. You been to Hitech in Wangara?
I am, as I've said, merely competent. But in an age of incompetence, that makes me extraordinary.