Re: chaning gear oil(lower unit oil)
LU gear oil should be filled from the BOTTOM connection. Buy one of the hose connections sold at the marine stores that will thread into the lower unit opening and a tube of new gear oil.
Remove both plugs from the lower unit. The top fitting is a vent, the bottom is the fill/drain fitting. The bottom fitting should have a small magnet on it. This will capture any shards of metal that will shear off the gears (if you find anything more than fines of metal, a closer, internal inspection is required).
Old gear lube should not contain any water, either. If you do find water a pressure and vacuum test MUST be run to find the leaky seal.
To fill, connect the hose from the bottom LU connection to the tube of new lube. Squeeze the lube in. Those hoses are fitted with a ratchet connection (valve) to pinch the hose. At this point, the tube will be nearly empty. disconnect the tube from the hose and refill the tube, the reconnect it. Open the valve and squeeze lube into the LU until you have lube dripping out the top connection. Put the vent plug back in, then the bottom plug. Be sure to replace the seals on those fitting before putting them back in.
Stores sell pumps designed to do all this, but I have found this the best and cheapest way to do it. With gas headed to 4 bucks a gallon
, I know where my money will be going
!
