140HP Mariner/Merc Starting and Idle issues when warm?

[Edwardcollins]

I just bought a 5 meter fisher plate boat and it has a 2004 model two stroke 140hp mariner on it with only 180 hours on the clock. I have used it a few times with no dramas but suddenly one day out at the reef it took allot of cranking to get it going and then once I did get it going it would stall if I just let it idle. Its very intermittent because sometimes I can go out all day and not have a problem but now its becoming worse. Fuel system has been completely over hauled trying to find the problem so now it must be electrical? Any help will be much appreciated.

 

[schematic]

did you take a good fuel sample?
water in fuel?

If no water, keep a timing lite with you and check for spark at each plug, next time its hard to start.

 

[tommarvin]

Whats a 5 meter fisher plate boat?
A fuel system overhaul includers this, how old is the gas carbs will run on old gas EFI will not
The gas goes from the tank to a fuel water seperator. You need the big screw on water seperator.
Then it goes through a on motor fuel filter need a new filter then it goes to a fuel pump.
Now you get to remove the carbs and clean them like all the you tube videos remove all the carbs tear them apart and clean all the openings with a wire on something fishing line weed wacker,whatever fits
If you did this, then its spark ,I think you need a inductive timing light like schematic said above, check for throttle advane with the timing light too..

 

[jimmbo]

I would like to see a picture of this 140 Mariner

 

[Edwardcollins]

New fuel, new water separator, mechanic also checked the timing. Fisher is a brand of plate boat here in Australia. Thanks guys

 

[jdaghir]

Has the fuel pump been rebuilt and ALL the fuel lines from the water separator up to the carbs themselves replaced? Doesn't do much good to rebuild the carbs if 14 year old fuel lines and fuel pump diaphram are deteriorating and clogging the carbs back up again. Idle jets are usually pretty small - doesn't take much to block them.