Re: Changing Water Impeller Rude 40HP Lark VI 1964
The first time you do it, it'll take the better part of an evening assuming everything goes well with no broken bolts. The next time will take a couple hours, perhaps less. Third time an hour or less.
Lower unit removal procedure:
1) Disconnect the shift wires next to the engine near the back.
2) Remove the back half of the midsection's exhaust shroud. There will be a pile of phillips screws that need to come out. If they're proving to be a hassle, invest in an inexpensive impact screwdriver. The kind you hit with a hammer.
3) Remove the access plate on the starboard side of the forward part of the exhaust shroud, and then remove the plate behind it. Snake out the electric shift wires so they're free. Soap helps. Do yourself a favour and first tie a string to the wires so you can use it later to feed the wires back up into the engine compartment.
4) Unbolt the lower unit and pull it straight down. You may have to force it with wedges if the driveshaft splines weren't properly greased. Don't worry, the only parts that can break are cheap.
Installation is the reverse of removal, but be sure to grease the splines and replace the o-ring on them if it's bad. Also, coat all the screws and bolts with gasket sealer or grease before re-installing. This will keep them from corroding in place.
Goop is basically what holds the wires into the lower unit, so be careful not to pull hard on them.
That will expose the water pump. Does your manual cover it from there?