ok thats good then I open them and also the balls just in case....even though it dont make sense to me if it's breather there no sign of any oil on the bottom.And it seems to me if air can escape from the bottom why can't oil.
The balls just seal drilled holes, they can be covered. The 2 smaller silver rough looking things are the breather vents, they need to be open. They breath through the DS rotor shaft is hollow drilled to a depth that puts it between the air side seal and the oil side seal and the bolt that holds the gear on to the rotor shaft (left hand thread one) has a tiny hole drilled in the center of it that allows the gear case to breath but being on center while spinning no oil can ever get to it as it’s all centrifugally kept away from the hole. Be careful flipping the blower around, it’s ok to flip it over just don’t stand it up vertically with the snout up or oil will get in that passage and then leak out through those vents when it’s back in it’s proper orientation. The SC only hold about 8 oz of oil and if you fill it incorrectly through the top hole you will put the oil right into that vent hole in the center of the gear bolt and it will leak all over once on the car. Neither the upper nor the The lower plugs are level plugs, the SC is filled by volume not level of those 1/8” plugs with magnets on them. Personally unless leaking or over heated leave it alone, the oil does not need changed unless there’s a ton of miles on it, like 100,000 plus or it leaked or was severely over heated. The SC has magnets inside it that filter the oil before it’s fed down into the rear bearings, super strong ones, see the nail the one holds straight out from it in the picture? Both bearing oil ports have them and their actually opposite polarity of each other to catch all particles no matter their polarity. There is a hole in the center of the bolt in the smaller gear, I couldn’t find a picture of it but trust me it’s there. That’s the vent hole for the gear case. See the breather next to the shinny ball? There’s 2 or them, don’t seal them over with the blanket or you’ll push the oil into the supercharger and into the engine and you’ll have no clue it’s empty till it fails.