Re: replacing a bellows
tilt the outdrive full up and hard over then inspect the clamps for the bellows and the shift cable. looking for tears cracks and corrosion, and or signs of water entering the boat around the drive input shaft, or water in the drive oil. water in the oil may mean a bellows failure or another problem. if the leak is not evident then pressurize the lower unit and find it, a radiator checker with a fill adapter works great for this. if the bellows is more then five years old then plan on replacing anyways. bellows are like impellers they shoud be changed regularly. if the bellows have flooded you will need to change the u-joints and shaft bearings to. older volvos are easy to do, merc can be a bit more difficult but still simple. the old omc,s are a major pain. if you have a merc change the shift cable at the same time so you dont have to due this again. for a merc you will not need the special trunion bolt socket a big allen wrench should due it.
if you have fooded a drive dont freek out yet, flush out the old oil, change the oil, fix the leak and try it out, if you have no weird noises, shifting problem or burning of the oil you are probably ok. mercs are more sensitive to floods then volvos. but most will live for years after a minor flood.
on the merc when a shift cable starts going bad it will die going into gear, always change the bellows everytime you change a cable, and check that all of the grounding wires are intact. it is also a good time for a impeller change and drive service.
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