I did my 50 hr service on my BX2660 myself a few weeks ago. I just made sure I went to the dealer to get my parts and told them to give me everything I needed to do a 50 hr service myself. That way I had a receipt to further back up that I handled it correctly (and I enter it in my User manual chart.)
They gave me way more than what I needed for the 50 hr, so at first I thought "what have I got myself into" But it was easier than I thought .
1) Engine oil change and filter of course was easy, like a car.
2) Airfilter,, although they sold me a new one, and 50 hr does not show need to replace ... I read about how it could be cleaned three times before replacing and mine was quite clean , I will save the new filter for the 100 hr .
3) they sold me 2 fuel filters too but not needed at 50 hr and both looked very clean.
4) Hydraulic oil filter was not too hard to do, a quick change and you do not lose much fluid. Get yourself a "band type " filter wrench , it is tight quarters probaly on your BX model too!
5) Hydraulic Metal screen cleaning was tricky from behind rear axle, you do lose a bit of oil , but if you plug quickly with clean rag tightly pushed in, you can clean the screen with varsol and dry and put it back in with only a cup or two of oil lost. They sold me 2 gallons of fluid , but you are not required to change at 50 HR. Dealer told me just top it up unless I see something abnormal . Will use the fluid at 100 instead.
6) torque all the wheel nuts, grease the machine , check a few other things and your done.
I learned a lot about my machine and saved myself $200 bucks.
jake