Re: Lower Unit
geo...look at the lobes on the clutch dog and gear. These mate when in gear. The mating edges should be sharp or will be rounded slightly from use. The lobe edges come into contact with each other as the engine is put in gear and over a period of time will round off. Extreme rounding of the edges will cause the engine to jump out of gear and back in while under way. May be OK at lower speeds but usually when extreme wear is the case, the engine will feel like you've hit a log when it jumps in and out of gear. Mostly the wear is caused by incorrect shifting. When shifting into gear, make the shift crisp. That is, get it in gear. Don't let the "gears grind". Engine idle should also be in specs to. The higher the idle, the rougher it is on the gears when shifting. If you are going to do any type of work on the lower unit, I highly suggest getting a service manual or the engine. iboats store offer generic service manuals that will cover several models. Usually the OEM manuals are the most detailed with info and graphics.
