2005 Mercury 125 2 stroke fuel problems

Bradley5715

Recruit
Joined
Mar 6, 2020
Messages
4
Okay so I have changed just about everything and still seems to be losing fuel pressure. Will idle and start out strong but after a short distance will slow down. Pump primer, and will keep going strong. I have rebuild fuel pump, replaced fuel line, changed fuel filter, and even put a small fuel tank beside the motor with a shorten fuel line. I took the pump off to see if I had good crank case pressure and it seems to be there. Any help would be great.
 
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QBhoy

Fleet Admiral
Joined
Mar 10, 2016
Messages
8,348
Is this an optimax 125 ? If so I’d be looking at injectors perhaps. Look for unburnt fuel out the exhaust too.
 

flyingscott

Fleet Admiral
Joined
Apr 8, 2014
Messages
8,291
Don't hook up an electric fuel pump. Does.it.idle.correctly? Make sure your fuel pump is.in good shape and rebuilt correctly. The fact you pump the.primer and.it runs good leads to a fuel pump issue. Are all the fuel.lines in good.shape no kinks. Are the carbs clean.and set correctly?
 

Faztbullet

Supreme Mariner
Joined
Mar 2, 2008
Messages
15,937
Since you rebuilt pump go inspect it as if you installed the rivets to tight it will buckle the rubber check disks and cause them not to seal.
 

Bradley5715

Recruit
Joined
Mar 6, 2020
Messages
4
Thanks everyone for the responses. Went out today with a glass filter right before the carbs and it stayed full with no air. I think when I pushed the primer ball before, I was over feeding the motor, which would make it pick up speed. I notice that the hotter it got today the worst it would run. I have changed the voltage reg. and stator a while back after finding burnt wires. I may try a trigger assembly.
 
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