Re: Lower unit stuck
Hooty's right, there are 7 (I ran out to the garage to check). So is does sound like you're stuck at the crank/driveshaft spline junction. Were this a Merc board, we'd be used to this situation (OMCs have better corrosion control than anyone). <br /><br />Here's the best solutions, drawing partly from experience working with Mercs. If the motor's running, I think the best solution is to loosen the lower unit bolts about a centimeter, then back the boat into the water with the trailer strap on, start the motor, and run it in forward and reverse a few times. I haven't had this fail to loosen the driveshaft spline on an OMC yet. Basically the gearbox housing, pushing back and forth by the prop, creates a torque (moment) on the exhaust housing, which becomes a tension on the driveshaft spline joint. Given the heat, vibration and impulse of running, the joint separates.<br /><br />If that doesn't work or if the motor isn't running, the Merc guys recommend loosening the bolts/nuts at the exhaust housing/powerhead junction, then "gently" dropping the combined apparatus from about 6" onto a rug. I can verify that this did work on a Merc 85hp. Examine the splines afterward and see how much damage you've done. You may not want to attempt to run to the Bahamas with this motor now. <br /><br />When you put it back together, obviously you want to grease the spline and run an O-ring to keep saltwater out. OMC gasket compound on the bolts holding the lower unit on, and on the mating surfaces, is also a good idea.
