If you have oil in your main reservoir you fill the satellite reservoir most of the way and then bleed the system. If the satellite reservoir does not start to fill when you loosen the fill cap than your oil pump is not working properly. It may not be working properly for a few different reasons outside of the pump being bad. The Merc is a pressurized sealed system if you have a leak somewhere it wont pressurize the satellite bottle, fill cap must be really tight, hose line connections must be tight. Lines are usually held on with zip ties make sure they are tight at hose connection.