Re: Tohatsu M50D linkage or lower unit problem
Sounds like a problem with the gears, unless your linkage adjustment is way off. If it is off, then what will happen is when you shift to forward, the linkage will move up, but not all the way, causing the cam to raise, but not all the way, causing the clutch rod to move forward, not all the way, allowing the clutch spring to move the dog forward, but also not all the way and thus not engage completely. <br /><br />As I recall, there is no adjustment on manual shift models. If it is such a case, you should be able to tell by not being able to shift into reverse completely, meaning that the lever will not go back all the way, yet already engage when running. <br /><br />Try the following test, while not running, spin the prop by hand in nuetral. Then put in Forward and try the same into forward direction. It will either be hard to turn or click. Then put a little pressure in the opposite direction, but not enough to turn prop. Note if the prop has any free spin without clicking. If it does, then put back into nuetral test again for free spin in both directions. Then into reverse and do the same. When shifting into reverse, you will need to play with the prop a little so as to line up the dog with the gear. Then back into nuetral and check the same. <br /><br />Make sure that you do not apply enough pressure when trying to turn the prop in gear to actually turn it. You are just seeing if the lower unit gears and dog have actually engaged. Make sure that the ignition is off and that the kill switch is out so that you won't start the engine by accident. <br /><br />If you have reverse but not forward, if reverse is hard to shift into even though the dog and gears are lined up, if it doesn't come out of reverse, or doesn't want to go into forward, then most likely, you have a bit of dirt or a burr in the clutch shaft area. The dog moves from F to N to R by being pushed by the cam, thus you can man-handle it into place. From, R to N to F, a spring pushes the dog forward as the cam releases the clutch rod, so no matter how hard you try, the spring may not be strong enough to move an obstruction. I had this problem before. It may go away on it's own, but then the burr is still in there, just floating around somewhere else. The lower unit is not hard to disassemble, and as a matter of fact, you don't even need to remove it from the leg in order to pull the propeller shaft housing and clean the parts. If you do decide to do yourself, and pull the housing, make sure to drain all oil first, and tilt motor up all the way so that you don't risk having the forward gear fall out. It is attached to the forward bearing and is basically held in place by the pinion gear from the drive shaft and the bearing race. If it falls out, you need small hands to get it back in. A manual (shop) helps because it will have illustrations of the internals of the lower unit. Good luck.
