how do i check lower unit grease or lube on a 1978 mercury 1150. and what to put in it if it needs it. is there a online site with all this info? there is a bunch of grease fitting on this engine.... thanks. im asking because mine set about a year before i bought it and when you engage prop forward or back there is a slight grid for a second then all is fine. it is idleing about 1800. i was thinking this could be it as well but not sure how to adjust the idle or what it should be set at...