Mercury will not plane out

[mickeyc]

I have a 1989 black max 135 I am having trouble with. It has always ran great but now I can not get it to plane out. Power seems normal until I go to full throttle and then I am just not getting the power it needs to come up on plane. it is almost like its not going to full throttle. I have checked the compression and all cylinders are at 140 except #3 it is 130.
The plugs are new. I don't fill any missing just low power. Thanks for any help Mickey

 

[Iceman66]

Re: Mercury will not plane out

Do a dva -output reading on your stator,maybe you are missing the high-speed winding from stator.
A bad rectifier can also cause this problem,disconnect the two wires from stator to rectifier and take it for a run.

 

[powderhoundbrr]

Re: Mercury will not plane out

I would be looking at the carbs. Give em a good clean and see what happens.

 

[Iceman66]

Re: Mercury will not plane out

Doubt this is a carb problem,the rpm would go up and down.

Check this,page 83 and 84: CDI Electronics Practical Outboard Ignition Troubleshooting