I see no need to invest any significant amount of effort or money until I know that I at least have a well running engine that doesn't sound like it is about to explode. I would not invest the time and money in repairing a major engine defect or replacing the engine. As such, the first thing that I would want to know is the condition of the engine. What I mean by that is that there is no point in spending money, time, and effort on new tires, a new battery, flushing fluids, new fuel pump, repairing a rusted fuel tank, etc., etc., only to find out that the total cost to get it back to a safe and reliable riding condition is beyond the amount of time and effort that I am willing to expend on it. I would get it started first. If the engine has suffered a major mechanical failure and needs a major repair or to be replaced I won't do that, so I need to know that up front. Once it is running I can further assess to determine whether going further is justified.
I would drain all of the fuel out of the fuel tank. Below is a link to a simple way to accomplish that. I wouldn't pull the fuel pump to examine it or the fuel tank at this point. Pay attention to the condition of the fuel that you drain out to see if it is full of water or not. There is no question that you will need to remove the fuel pump (and probably replace it) and inspect the inside of the fuel tank for rust if you intend to put this motorcycle back on the road but I wouldn't do it if I don't have to until I know whether or not the engine runs and how well it runs. There is always the possibility that you will have no choice but to do this in order to get it to start if the fuel pump is all rusted out but you have nothing to loose by trying to start it first.
I would put in two gallons of fresh fuel and make sure that there is engine oil in the crankcase and anti-freeze in the radiator and then connect a known good battery to it. I see no reason to spend money on a new battery at this point- Connecting a car battery to it using booster cables is fine at this point. The fuel pump is located in the lower fuel tank under the passenger seat. In a quiet environment, with the engine kill switch in the run position, turn the ignition switch on and listen for the fuel pump. It should run for about three seconds after the key is turned on. If it doesn't you will need to diagnose why, which may well be a rusted fuel pump/tank. If the fuel pump does come to life you have nothing to loose in trying to start the engine. Crank the engine over and see if it will start and run. If it won't crank or start and run there is no point doing anything else until the cause of this is determined, which again may well bring me back to the rusted out fuel pump scenario. If it does start and run I can then further evaluate it to determine how well it runs and if there is any obvious major defect that needs to be further investigated. If the engine runs fine then I would move on to evaluating the rest of the motorcycle, including examining the inside of the fuel tank and the fuel pump. I would then proceed with going over the whole motorcycle to see what needs to be replaced or repaired. After that evaluation has been completed, and if it is still worth investing my time and money in to it, then the end goal becomes going over it from end to the other and accomplishing all of the maintenance items that will need to be brought up to date to make this a reliable and enjoyable ride.
Draining The Fuel Tanks
