! How many hours on the unit? Maybe the seller's will allow you to pull an oil sample? SE'S and SG's have been fairly reliable compared to their newer cousins, the "J" and "K". A lot depends on the kind of maintenance the machine has had. Something to try (a quicky without actually flow testing) when looking at the machine. With the seat facing front and with the engine at idle, start raising the loader boom and then turn the seat towards the rear while raising the loader. Does the loader pick up speed and start to rise faster? If not then there could be an electrical issue or a pump issue (pump runs about $2300 + labor). While this is no guarantee of pump condition or overall machine condition it will give you an idea if pump problems are starting. Good luck with your decision.