150 Mag II....only turning 3000RPM @ WOT

[Scanos]

This is my best friends boat and I am helping him troubleshoot.....I was thinking initially highspeed stator but wouldn't that hit a wall at around 1600-1800 rpm instead? i have a DVA ordered but won't be hear until Monday.....are there any other tests that I can perform with a VOA until then....is it possible it is fuel related? Basically in a nut shell it winds up nicely with no bog up to 3000 RPM with a load and then that's it...will hold 3000 all day....needless to say the boat won't plane at that RPM. It will wind up to 6000 with no load. Thanks for any help offered.

[dynobo]

If you have a timing light connect it to each plug wire and attempt to accelerate. IF all 6 are responding at 3000 rpm then you may have a fuel problem, but my guess is the stator. If one bank of cylinders is shut down then you probably have a bad switchbox. If you have a similar motor (40 amp), just swap your stator over to his. In my experiences with carbureted NON distributor motors, the Merc/Mariner are usually the easiest to troublshoot.

[Dave S]

Stators........Try that you no good merc.:eek: My best .02.;)