At least the engine oil filter has been changed once. It should have been changed about 5 times by now. Ask him how many times he has changed the oil/oil filter and what kind of oil he put in it. My
B2920 still had the gray hst and hydraulic filters when I bought it. That didn't worry me because it only had 112 hrs. 800+ without those being changed would give me a little more concern. I believe the hydraulic fluid should have been changed twice by now. I would be skeptical about the hydraulic fluid having ever been changed since the filters have not. I can't remember if you said anything about the look of the hydraulic fluid. Does it look fairly clear? It was talked about how the owner would have been smart to change the hst and hydraulic filters prior to putting it up for sale. It could be he got some of it right (in the wrong way) by changing the oil filter and oil just before putting it up for sale. Could it be that gray oil filter hasn't been off long? Then there is the coolant thing also. I would proceed carefully. Check for leaks thoroughly around the engine and underneath everywhere prior to running it. Then check again thoroughly after running it long enough to get all the fluids hot.
I know what you are going through as I just bought my
B2920 two weeks ago. Fun and extremely stressful all at the same time. I certainly don't want to discourage you, but do want you to be satisfied down the road with what you get. It is hard to keep the buying fever in check.