Re: looking for a used motor
Is the 50 not enough? <br /><br />On the OMCs, the 50-60hp twin (40 to 40+ cubic inches) is a good motor. Needs to be spun to make power (not much low end). In my experience, the HP rating on these might be a bit optimistic. Good fuel economy.<br /><br />The 60-75hp triples (50 or 56 cubic inches) have a good deal more beans than the 50/twins. More low end, though they will wind out on top too. Decent fuel economy. <br /><br />At 85/88/90hp, you can get into the 100 cubic inch V4s. These will 'feel' a lot stronger than the triples, AND will drain the gas tank a LOT faster.<br /><br />Be aware that HP ratings changed in 1986. A 1986 90 is same as a pre-1986 115, etc..<br /><br />I think the picks of the litter are the 70hp triples, or the 1986+ 88SPL, depending on how much you value power versus fuel economy. Both are great motors. <br /><br />The 88 has a really sweet powerband, and probably the best reliablity record of any larger OMC outboard. The 90 is the same motor, but with VRO. On the V4s, I would not go earlier than 1986, simply because the earlier 85/90 V4s are too detuned on top for all that gas they use. On a heavy cabin cruiser, good choice; but on a Tenn bass boat, you deserve some top end.<br /><br />On the triples, there's no reason not to buy an earlier one - back as far as the 1973 65hp, first year of mechanical shift. If you want power tilt, stay with the 1979 or later; the earlier power tilt units are a little flaky. <br /><br />Keep an eye on the middle cylinder compression on the triples - if they run lean or hot, that's where they often fail first. On either motor, compression should be with 8psi, highest to lowest, across all the cylinders. Ideally just 2 to 3 psi variation.<br /><br />Enjoy!
