Hi all recently purchased a gsxr1000 k7 which has been sat for 3 years with fuel in the tank the fuel pump is shot so I've ordered a new one but there's rust in the tank what's the best way of cleaning and getting rid of the rust ?
You can use a strong acid with some nuts and bolts in it (dangerous in that you can splash acid on you), you can use electrolysis, you can buy one of those gallons of rust-remover they sell at the hardware store (more expensive), or you could buy an entirely different tank.
P.S. I continue to like the rotating tank filled with drywall screws method. There are several variants that relate to how the tank gets rotated, i,e. clothes dryer, small cement mixer, jacked up lawn tractor wheel or car wheel. I'm suspicious of the car wheel as you don't want it turning too fast. Drywall screws ought to be better than nuts & washers because of their sharp, hardened edges. Perhaps nuts & washers to finish things once the rust is removed.
2 gallons evaporust from harbor freight, $12 a gallon, follow instruction, fill, rotate every 8 hours for 24 hours so every spec is removed, it takes it right down to clean shiny metal, no work, if you want to fill the tank you won't have to spin it to hit all spots, of course tape it off all that...
only thing is its bare metal from there, I believe these tanks have some sort of treatment or something and when a tank rusts that's all gone, they tends to rust easier from there on out using ethanol gas which attracts water right out of the atmosphere..
if you can find an ethanol free gas use it, keep tank topped you;ll have no issues, at least when storing for long periods, 3 weeks or longer, pure-gas.org..
you can remove the alcohol from the gas easy enough, videos all over youtube, really want e free for storing
I always dump the evaporust back into a container and save it, then rinse with water, dump, then use a half a quart bottle of 99% alcohol and rinse it around, dump, other half bottle alcohol, rinse around, dump... you really want to time this so that once the alcohol comes out the fuel pump goes on directly, mount tank onto the bike, connect everything and filled within like 10 minutes or so, fill with a gallon at first wait a few minutes see if pump leaks if not fill er up..
have everything ready to go while tank is derusting, go go go, again Ethanol free is your friend here, if you can find a clear race jug with a spigot on the bottom you can fill with e10 whatever unleaded, then add a cup of water or so, shake around a few times, water bonds to alcohol sinks to the bottom, syphon it off with the bottom spigot, E free gas..
watch a few youtube videos of the ethanol separation process they have it dialed in to the exact amount of water and soak time so forth, well worth it if your bike sits days at a time, especially long periods, always top off, maybe even clothes pin fuel and vacuum line then run the carbs dry so carbs have nothing in them, or use the drain plugs.. this is going to save you time and money.. if you ride every day every other day E unleaded is OK, keep it topped off if ya can..
I never reseal my tanks, my 600 is still bare metal after a few years now, but I start it once every 2 weeks or so and keep topped off with E free.. also if you find e free but it's 87 use octane booster to pump it back up.. some stations have a 101 E free, works well, if on budget make your own E free, keep her topped off when not riding