I took it upon myself to service the final drives on my 2013ish 303.5ecr -- It has the three hex plugs, 2 equally near the outer edges of the cover plate, and one smack in the center. My assumption is the lowest is drain (either one near the edge) and the center is the fill + level check. Odd thing is that going by this, I can drain everything out the bottom, and when I go to fill via either the top or center, it's maybe 2-4fl oz of gear oil, then it starts flowing out the center. I can jam the gear oil thing in and try to pressure-feed it in, but just comes out the same hole with more force... Is there a kind of trick to this? Any kind of gear oil thing i've ever dealt with is drain X amount from the low plug, reinstall, then fill close to X amount until it comes out the fill hole. Manual says the same.
Post a machine Serial Number please. I’ll upload the procedure from the manual - which TBH if you do your own maintenance you should really have your own copy
The trick is to fill it from the drain plug, with a hand pump. Overfill slightly and when you pull the pump out to put the plug in you'll still be at the full mark.
How easy the oil goes in usually depends on the position of the planetary gears inside the final drive. You could try rotating the final drive a bit, say fill point at 1 o'clock instead of 12 o'clock. That only works if the level check hole is in the center. I've had to fill compartments from the drain hole before but something about that doesn't feel right. In those small final drives I usually give a pump or two before I put the drain plug back in, just for good luck.
Thanks for all the advice, I'll give that a shot. I'll grab a maintenance manual though - the owners manual trivialized it which made me initially think I was just being dense but it sounds like there's a trick to this.
I've got the same lay out on my 304.. I put the drain in the 6 o'clock to drain the oil and then reinstall the plug and fire it up and then turn the final until the fill is at the 10 or 2 o'clock position to refill until the oil comes out the center fill level hole