According to Moss, filling a supercharger with oil to the bottom of the fill hole is too high.
https://www.google.com/url?q=http://www.mossmotors.com/graphics/products/instructions/C2257A73.pdf&sa=U&ei=ELOMU_eTIoP5oATW7ILAAQ&ved=0C BcQFjAA&usg=AFQjCNFrkC1jhZtMsEZFc0IbUisaV-aoMg

Eaton does not help as to fill “level” because they mention only the fill “volume” when dry. This volume is 7.3 ounces for my unit.
http://www.eaton.com/Eaton/ProductsServices/Automotive/AutomotiveAftermarket/Superchargers/FAQ/


Background:
As part of my coolant hose replacement plan, I have the supercharger off the car and went ahead and removed the hex key fill/drain plug. Initially, no fluid came out probably because I had the unit nose down and the fluid ran down the snout. Anyway, after trying different orientations I was able to get fluid to exit the hole. Fluid flow could be encouraged apparently by slight rotating the pulley. At one point I left it to drain into a pan and the fluid missed the pan going across my workbench (yuk) and I am unable to measure the volume of the fluid removed however I think I got most of it out. I’ve added about 6.5 ounces of Motorcraft SC oil and it appears to be at the bottom of the fill hole when the unit is level.

I just want to make sure that I’ve not overfilled it.

 

Sounds just right. I got two 4 oz bottles of SC oil and had a small amount left over.

Not sure why they are making a big deal out of volume or level. I just fill it to the bottom of the threads on the plug and call it good.

If you do over fill it generally comes out the front seal so it makes a big mess and most likely tore up the snout seal.
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