I just purchased an 1971 sterncraft with chrysler 85. The lower unit is leaking oil out of the little hole under the fill plug why would this weep oil?
Is the leaking oil gearcase lube, or exhaust residue oil (would be grey/black).<br /><br />If exhaust residue, it is just unburnt oil draining from the motor leg.
Its a gear case lube. I bought boat was not visable got home and noticed some oil. when i tilt the motor i see it coming out not much but enough to concern me.(Im worried there is a seal that is leaking and if i use the boat the lower end will seize up)
That hole you mentioned is an exhaust port and is a difficult place for gear oil to get. Rub your finger in it and take a whiff. This is a common place for oil gas mix as Roscoe mentioned. Lower gear oil has a nasty smell and smells nothing like gasoline. If it smells like gas it is unburned fuel. It becomes more apparent when you tilt your motor up because the floats in the carbs can not hold the needle valve closed and more gas starts pouring out the carbs.<br /><br />If this is gas oil combination (usually looks foamy white or gray) decarbing motor may take care of some of this. Early 70s and late 60 chrysler technology basically had drain valves for condensed gas to drain down the motor leg and the exit is those holes you mentioned. If you want to verify the integraty of your lower unit remove the drain plug for a few seconds and see if the oil coming out is almond colored or white. White means water is present in the lower unit. If oil is leaking out then water must be leaking in.
