Home › Forum › Ask A Member › Best years for OMC 10 horse? › Re: Best years for OMC 10 horse?
There is a carbon seal that the driveshaft roll pin compresses into the bottom of the crank/powerhead. This circulates oil mix that drips down in the crankcase and helps keep the motor lubricated. If this seal is missing, broken, or in most cases, the roll pin on the driveshaft is not replaced or broken when people service an impeller, than the motor runs without proper lubrication leading to accelerated wear and tear.
If you take a look at a parts diagram in the gearcase section you’ll see the parts we’re talking about. Basically a couple of cups, spring, seal, and metal ‘washer’ type thing that sits on the bottom of the crank. Both the 5.5 and 6hp motors share the same design. I mean, basically the 6hp is a 5.5 with needle bearings (slightly tuned carb….?…thought it was just the switch to needle bearings that upped the HP by 0.5)