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1983 115 hp Mercury Outboard no output after 2700 RPM

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snowballak22

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I have a 1983 115 hp Mercury Tower of Power inline-6 that has no power after 2700 RPM. I've had the Link and Sink set by a certified Mercury Technician along with the carbs cleaned and properly set. It has set for twelve to fifteen years. All off the fuel lines have been replaced. Fuel tanks cleaned and new fuel added with 50:1 mix. New fuel filter and Mercury fuel connection to motor installed. I know that WOT in neutral is bad thing, but I did it once and it ran up to 4000 RPM. There is 115# compression in all cylinders. From what I have found that there is a Stator that has a Low and High Speed windings and this maybe the cause. Not sure where to go from here. Should all the electrical parts be replaced at the same time (Stator, Trigger, Switch Box (2), Coils (6) and .....) or is one at a time ok. I'm pretty sure that 115 hp Merc still has its original parts. thank you in advance for any help.
 
Download the CDI Electronics Troubleshooting Guide here:

http://www.cdielectronics.com/support/

The section for 6-cylinder Mercury ADI systems starts on Page 84 of the manual.

Many times a resistance check with an accurate meter will spot a bad stator, but ultimately you may need to purchase a DVA (Digital Voltage Adapter) to be able to read the high-voltages produced by the ign system, for troubleshooting.

HTH..........ed
 
The trigger and high rev windings sound reasonable, but they would hardly fail at all 6 simultaneously! The motor would lose a couple of cylinders and run rough.
My bet is fuel line pressure!
Fuel pump membrane, the vacuum hole to run the pump assembly somewhere there.
Try pumping the ball while running, may or may not give an indication, but it is a first easy try
 
Bad hi-speed windings in the stator Most Definitely can limit the rpm, so best not to discount that possibility until the stator is proven to be good.

I've had stators in the past that drastically changed resistance when hot, so it might be a good idea to check the stator cold, then take it out on the water for more testing (including the below).

Here's a blurb from the CDI Elex. troubleshooting guide that is appropriate:

HIGH SPEED MISS OR WEAK HOLE SHOT:
1. Disconnect the rectifier and retest. If miss is gone, the rectifier is usually at fault.
Remember a problem rectifier can damage a stator.
 
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