I have a rude tracker 40hp motor that came on a pontoon i just purchased. I went to check the lower unit gear oil, and noticed that the bottom drain/fill screw is loose, the next screw up is loose, the next one up is loose, and the top one under the cav. plate is loose. The bottom one is a flathead, middle two are phillips and kinda long, and the top is a flathead. Im going to tighten and refill the L/U, but I dont know which screw to leave out to tell when its full. I would think it would be the top flathead screw, but its nearly at the level of the water pump. Does it fill that high with gear oil? Or am i looking at the wrong screw? Thanks!
(no, none of the screw holes are marked full/vent)
(no, none of the screw holes are marked full/vent)