On a mercruiser o/d you have a gasket between the o/d and the bellhousing.This could cause a slight leak.You also have 2 rubber bellows.one for the shift cable and one for the drive shaft.Check between the grooves for cracks.These are usually where a leak is from.The gasket should be replaced everytime you remove the o/d and the bellows should be inspected every year.they usually last 4-5 years. CC
Get a clymer manual to help you through it.Everything is done from outside the boat except the shift cable inside the shift bellows.The motor does not have to come out.I would not attempt it without a manual.CC
