i clean my bb4 pump at the end of the year, or if i suck some sap up, with diesel. i usually let it run for half an hour or so, then drain and fill back up with oil. On the subject of oil turning yellow/white... i bought a large container of pump oil last season that would be clear when cold, then once the pump would run, would turn cloudy for the first 20-30 minutes, then would be crystal clear. can't recall the brand, but i was told it was normal for some oils? not 100% sure if that's correct, but my pump preformed normal with it. for what it's worth...
Awfully thankful for an understanding wife!
“The only place success comes before work is in the dictionary.”
- Vincent “Vince” Lombardi
Good luck to all!