I used gasoline, dangerous I know but old habits die hard .

As Leathermang mentioned is important to tip it towards you so any old dirt/crud/swarf will wash down and out .

use lots of lint free towels here and don't do this until you're ready to install and fill it up .

I always add a rare earth magnet from Harbor Freight ~ $6 buys you a tube of five and once you see the collected swarf you'll be a believer in drain and fill plug magnets .

__________________
-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better