[crossy]

I agree with Mike Reeh on this one about the fluid changes. In addition ,break the fuel fitting loose at the carburetor and put a rubber hose on it to redirect the fuel into a container(or down at the pump). crank it over until something comes out. hopefully it will be clean. if it is brown and smells like turpentine it's BAD fuel' and will probably be varnished up inside of everything where it was laying. I have seen fuel go bad in a few months and I have fired up old trucks that were sittting for 6-7 years. Pump/siphon as much as you can out of the tank and add 5 gallons of fresh and crank it till it comes out at the disconnected fitting.
They stink BAD and run terrible if the fuel has gone bad . but I have sucked the tank down and run 5 gallons of fresh through it and it cleans everything back up again with a can of fuel additive. With the beast that you are talking about it is only going to take 25 miles to run 5 gallons of fuel through it :-), DAVE