2001 yamaha 115 weak spark please help

bcas

Recruit
Joined
Jun 2, 2009
Messages
2
the left side of the engine has weak spark ill pull the wires on the right side while running and the engine almost dies i do the same on the left side and not much rpm change. starts and idles fine just loss of power and a little hesitation on acceleration i rebuilt the carbs but they were clean checked the fuel pump looked fine. i tried squirting fuel in while running in each cylinder and it bogged. i get on the throttle and see fuel coming through the main jets on all cylinders and im just at a loss please any input here would be great.
 

bcas

Recruit
Joined
Jun 2, 2009
Messages
2
Re: 2001 yamaha 115 weak spark please help

nobody has any thoughts here
 

blared

Cadet
Joined
Jun 3, 2009
Messages
23
Re: 2001 yamaha 115 weak spark please help

Sounds like electrical problem. I would recommend the 6 step voltage test with your volt meter. First check your battery, weak battery can cause low voltage or misfire on some cylinders. Check your battery cable voltages, If everything is good check the voltage on your ignition coils. Good luck.
 

cousinabe

Senior Chief Petty Officer
Joined
Nov 13, 2001
Messages
765
Re: 2001 yamaha 115 weak spark please help

check your stator output.
even though the tune up guide calls it high and low speeds its actually port and stbd bank.
lose 2 cylinders on one bank and its almost always a stator failure.
 
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