Where's the chain drive case fill at? Or do I just tip the machine a little?
If it's anything like a 1845C, just remove the chain case cover/inspection plate and pour it through there. SimS
Attached is the page out of the 1845 owners manual. They forgot to include a picture of the covers/access hole for the chain boxes but they are rather large covers on top of the chain boxes four in total. If only changing the oil only one on each side need to be removed but on a "new to you machine" I would suggest checking the chain adjustments so all cover need to come off. In picture the red arrows point to the chain box drain plugs. The green arrows point to on the right side the hydraulic tank drain plug and on the left the fuel tank drain plug. If you need the chain adjustment info just ask!
I have a 1835 c the book says to put it in the hole at the hyd motor but I drilled a 1/2" hole in the top of each tank and thrided it used a bolt and rubber o ring after putting the oil in
Not sure I'm understanding this, where the book says to put oil in by the hydraulic motor it is referring to oil for the gear reducer that the hydraulic motor runs. That is completely different oil than the oil for the chain boxes. The chain boxes oil is put in through the chain inspection covers on top of the chain boxes.
on the 1835 c there is a very large allen key between the tires on the side you are to take out that plug and put the oil in through that hole I don't have that size tool so I put a hole in the top inside the cab and threaded it for a 1/2" bolt
Well I guess you do what you need to do, myself I would have just purchased or even made the tool to remove the plug. A little imagination with a hex headed bolt that fits the plug and you have the tool! In the original post you said "I have a 1835 c the book says to put it in the hole at the hyd motor" so that's why I said what I did! I'm assuming the plug you don't have the tool for is #9 and seal ring #10
that is the drain plug the round hole is where the hyd motor goes on the inside and the plate the goes on the outside has a plug in it that is where the oil goes in ok