Mariner 115 help

[monark1800]

Last Monday, I launched my boat, pumped the ball a couple of times, then tried to start. No fire, pumped the ball,still nothing. Repeated this several times before realizing kill switch was off. Boat immediately started.
The water was rough, so it was a long low RPM ride to the fishing spot. Later when I tried to run fast down the lake, the motor would bog down, then rev up and down. Eventually ran fine.
Saturday, I took it out in 35 degree temps. Not running very hard because of the cold. Boat started missing real bad and cutting off. I found if I bumped choke it would clear up momentarily. Loaded up and went home. Changed ball out because it wouldn't get hard. Boat started,

Help!! missed badlythen wouldn't start. Changed plugs, still won't.fire.

 

[Bondo]

Re: Mariner 115 help

Ayuh,... Sounds like Water or other Crud in yer fuel,...
Check the Filters, 'n if Crud is found, ya might haveta clean the carbs...

 

[monark1800]

Re: Mariner 115 help

Can that be done without buying carbon kits? Changed water separated and found no water in it.

 

[CharlieB]

Re: Mariner 115 help

Use a small bowl, pull the float bowl drain plug and catch the fuel. See what comes out. Pump the primer to 'flush' each carb to see if anything ugly drains out. Repeat on each carb.

Sometimes I spray a bit of carb cleaner into the carb vent, maybe even remove the idle mixture screws and rinse them out as I flush the carb.

If this doesn't cure it, it is time for a full carb disassembly and cleaning.

Just noticed your statement about replaced primer bulb, check to be sure none of the carbs are flooding, also check for air sucking into the system, aftermarket quick connect fuel fittings often fail to seal well under vacuum. They hold pressure fine when pumping the bulb but still let air suck in as the fuel pump sucks on it.

Temporarily replace a fuel hose to the carbs with a clear hose, start the motor and watch for air bubbles passing thru, indicating air sucking in before the fuel pump. Replace the clear hose when finised, it is only for testing and potentially hazardous to continue use.

 

[monark1800]

Re: Mariner 115 help

If a carb is flooding, will gas run out the throat of carb while squeezing bulb? Are the bowl drains easy to get to?
The clear tube is not an option yet, the motor wont start. It does have a healthy flow from fuel pump while cranking tho.

 

[CharlieB]

Re: Mariner 115 help

Pull the spark plugs and check for spark on each wire with an adjustable gap spark tester set to 7/16 inch to verify the ignition is functioning correctly.

It is possible for the motor to be severely flooded and/or the spark plugs to be fuel fouled.

Pull the lanyard to kill the ignition, leave the plugs out and crank the motor for 15 - 20 seconds, rest the starter a few minutes then repeat. Do not overheat the starter.

Clean the plugs and allow to dry, reinstall and attempt to start.

 

[monark1800]

Re: Mariner 115 help

Update: found out yesterday that the new fuel line is crimped just upstream of the bulb. As long as I squeeze the kink to open it up, the bulb will get solid. Motor then fired and ran fine.