There is a crack in my lower unit gear housing beginning at the hub and forward about 3 inches. I took it to a welder and he said that the aluminum was too corroded to accept a good weld. The crack doesn't seem to affect performance and no water is leaking into the actual gear housing. I am thinking of Continuing to operate the unit in its present condition. Would appreciate any advice. Do you think it worthwhile to fill the crack with some sort of epoxy filler?