I have a bad oil leak on my 87??? 25hp Mariner. The oil is coming from where the lower unit bolts to the upper part. Coming right out of the little crack. The oil doesn't apear to be LU oil but more exhaust type oil. There are several small holes in the casting around the water intake and the oil seeps out of these also. I do alot of idiling with this motor and was wondering if this is making the motor load up by not cleaning it out. Any clues to why the oil would be coming from the mating surface of the LU??? I will try and get a pic of where the oil is coming from and post it up.