I'm sure this also applies to other similar NH machines as well. My oil cooler return line had worn through where it passes through the frame/engine mount area so needed to replace it. Apparently they redesigned it by using a hardline from the cooler to the front under the seat and then a regular hose from that to the control valve. Because of this you need to lower (or remove) the fuel tank so you can gain access to put the hard line in. Here are the steps to remove the tank (most steps are in the service manual but lacking info towards the end): * For full tank removal you will need a bit more clearance from under the machine so raise it safely on blocks 1. Lift boom and lock 2. Open rear door and raise hood 3. Remove left side engine bay cover 4. Remove left side fender (above wheels) 5. Remove the rear belly pan (under the engine) 6. Disconnect the 2 fuel lines on the top of the tank 7. Disconnect the fuel level sensor (2 wires) 8. Disconnect the filler spout/tube 9. Drain the fuel from the tank. Underneath the tank, disconnect the tube that connects to the front of the tank. Underneath the seat is where you will find the other side of it. Both sides are held by a regular hose clamp and of course the one under the seat faces away from you to make it harder for no reason other than giving the assembly workers a chuckle at what's to come about 2000 hours down the road. I have a 12v pump to fill the tank so I used it to remove most of the fuel through the fill spout and the rest from this hose at the bottom of the tank. 10. I'm doing this by memory and feel like I'm missing something obvious on top of the tank, but maybe not. Use common sense. 11. Here's where the manual is vague. It says to 'remove fasteners' or hardware from the fuse panel and lift it up and out of the way. There's more to it than that. The left fender that you removed in the beginning? You need that out of the way because even though the fuse panel is loose, the bracket that it was mounted to is still in the way and will block the front end of the fuel tank from pivoting up. The tank has to be removed by tilting the rear of it down (hence the front pivoting upwards towards the bracket) and eventually pulling it down and out. This bracket needs to come out and is held in by two bolts that are kind of hard to see from outside the frame, in between the rear wheel and the frame. Removing those two bolts will allow the bracket to be removed. Before removing the bracket you will probably need to disconnect the ground wires that are in the way first. One bolt holds the wires down. 12. Remove the tank fasteners. There are two. The front of the tank is held by a small bracket and one bolt on the inside of the cab under the seat. The second fastener is right near the fuel filter in the back and is kind of a pain to remove as well because you will probably need another wrench to hold the back side, which of course is hard to get to. 13. At this point the tank should be able to be removed. Mine was stuck to the point where I thought I missed some fasteners but it was just stuck with years of gunk. Again, the rear of the tank needs to pivot down and once the fill spout and top of the rear tank clears the frame you can then pull the tank back and out. This was kind of a lot of work. Like most things I could probably do it again much quicker next time but I don't want to. Regarding my issue with the oil cooler line, if I had to do it over again I would just have a new hose made up and replace it without having to do any tank removal (actually it was enough to just lower the tank in my case but it's literally all the steps anyway). Hope this helps someone. In my google searching I saw 'skid steer mechanics' saying the engine needs to be pulled out to remove the tank and I knew that was wrong because the service manual does give most of the steps and now I know for sure.
I just replaced the fuel tank in my ls170 and I printed your steps and had no issue. From start to finish I’d say was around 5-6 hours. I’d say at least a couple of hours lifting and lowering was the biggest issue. While doing job I also replaced the common 3/4” hose that connects front to rear. Thanks for your post BobbyP