Re: Lower Unit Oil Anybody
You don't state the year which is important. Later Forces had different lower units than earlier. If you have an earlier (pre-1990) lower unit, and if the oil is leaking from behind the prop: Drain oil. Remove the prop. Remove the anti-corrosion anode (two screws). Check to see if leaking is coming from around prop shaft where it exits the spool or from the circumference of the spool itself. If it is, remove the four bolts holding in the spool. Buy new bolt O-rings for re-installation. Make a puller from all thread rod. Pull out spool and check condition of seal. If seal is as bad as it sounds, (usual wear will cause weeping-not gross leaking. Sounds like rubber in seal is almost completely gone.) check prop shaft for straightness or roughness. Buy new seal from local Mercury dealer and install in spool. Note position of old seal in spool and install new in same direction. If it is not the seal, It could be the O-rings around the spool or corrosion of the gearcase. Check for corrosion and be sure the gearcase is perfectly circular--not bent, so O-rings can seal it. But you have the spool out so you might as well buy the two O-rings and replace them anyway--good preventive maintenance.
