Mercury Keikhafer problem....

[CALVINIST]

Yesterday when I was out on the water, I was going full throttle when suddenly the motor jumped out of high gear. Fortunately, it runs in low gear, but I could no longer get in to high gear after that. When I got home I took off the prop to see if there was a shear pin, and I did not see one. The only thing I saw was the ridged shaft thea the prop slides onto. Any ideas what the problem is?

Thanks in advance.

[Valv]

I would suspect clutchdog inside gearcase. Check your cable linkage for adjustment, if it's a tiller you might have to to take it to a shop to have it fixed.

[Whoaru99]

Time to upgrade?

[MN621]

Perhaps you could describe what you mean by coming out of high gear. I'm not aware of any outboards that have multiple forward gears. Does the engine RPM go up but the speed goes down or is the engine laboring? Depending on which it is, I might suspect a slipped propeller hub(high RPM) or a cylinder cutting out due to a bad plug, plug wire, or ignition coil(laboring engine).

[Shack]

Ya! I know guys with Ford 6.0L diesel eng.'s with inj. concerns that swear it’s the tranny. I also know guys with coil over plug failures on their 4.6L and 5.4l and v10's that swear the same thing. In their case it's the plug or coil over plug. This could be the case. If I were you I would get a set of cup's and run eng. in drive way and see what prop is doing. Do not loose a finger, but I would be interested in seeing what prop is doing. At this time you can check for a plug issue as well. I would disconnect plug wires (one at a time) and see if there is any difference in eng performance with plug wire taken off. If you pull a plug wire (one at a time) and you get to one paticular cly. and there is no change in eng. rpm's, you have found your dead cly... When a cly. is operating properly (Spark and Comp) rpm's should change. If your motor would have only on plug, that’s a different story. Good luck