Re: 1987 45hp mariner ? help
Hi Stereoguy,<br />Your 87 45 hp jap crap was made in Fondulac<br />WI. In the Mercury Marine Plant. It is the same motor as the 4 cyl Classic 50 Merc. The motor should idle at 650 RPM in forward gear most all day. I don't think that the stator<br />is your problem. When the stator doesn't work<br />your motor won't run or rarely run. A strong 45 HP has 125# compresson. Gauges vary in how they read so your in the good range. I think the motor has an air leak in the crankcase,bad gasket maybe, or the carbs need<br />new needles in the seats and the idle adjusted by someone who knows what they are doing to sync the spark advance to the throatal position. I set them 2 degrees advanced from the factory setting for the pickup and dead on for max advance. The carbs are set at one to 1.5 turns open depending on what the motor wants. Use L77-JC4 Champion plugs or NGK equivlant set at .040.<br />As for the shaft,the cavatation plate should be even with the bottom of the boat. The motor is made to run on a boat with a 19 to 21 inch transom with 20 in. being ideal. Measured from the top of the transom to the bottom of the boat. Max RPM is 5500,so set it up to turn max, then the prop pitch will be small enough to troll slow. Use Merc premium tc3 oil for a clean burn, it has more deturgents in it to kep the pistons clean. Once or twice a yr run a spray can of <br />Merc Power Tune through the motor to clean the carbon out of it. If you need to drop the motor 2.5 inches use an after transom to<br />do it. The extension kits are 5 inches and don't work that well for long service.<br />Get a new service center, the only difference between the motors is yours is grey and theirs is black. If they don't know that, what do they know?<br />...have fun...corm<br /><br /><br />------------------<br />cubic inches = power<br />power = speed<br />speed = FUN