Cleaning out the gas tank?

[jtolbert]

So, my spiffy "new" '83 GS1100GL's gas tank has been sitting with old gas in it for a while and looks to have some rust inside...Nowhere near the worst I've seen, but I'm interested in cleaning it up as much as possible.

Are there recommended vendors to get a replacement petcock/strainer from, or should I just take mine out, clean it up and re-use it? It flows fuel fine, but the lever is hard to operate and I'm not sure what condition the strainer is in. The bike runs fine with the petcock it has, so I'm curious which way you all would go.

Is there a good way to clean out the inside of the tank? My Dad suggests throwing in some carb cleaner and BBs, but I'm not sure about that.

Thanks.

[MissFabulous]

For cleaning the tank, all the research I've done tells me that the POR-15 kit (about $35) works better than using Kream, which can cause problems down the road for some.

Carb cleaner won't likely deal with the rust... it's designed to melt away the gunk that old gas leave behind, not rust, which is chemically very different.

As far as the petcock, the rebuild kits are supposed to be junk and it's better to replace then instead of rebuilding. All three of my bikes have petcock levers that are really hard to turn, but whether or not it's gunked up is another matter. No doubt someone else with more experience will chime in on cleaning it properly. If it worked, it's probably fine, unless you find out it has revving or other fuel issues, then it's a good place to look. I'll let smarter and more experienced brains take over from here :-D

[gustovh]

Well I ran across a thread a couple weeks ago on removeing rust from the tank useing electrolisis. I beleive that it would work well in you case, and without a lot of rust in the tank now, after treatment you would not need a liner, just keep it full of gas when you are not riding it and you will be OK.
As for the valve, take it off the tank, remove the 4 screws holding on the back and carefully remove the back, there is a spring on the vacume side so be careful. I bet that you will find a fine orange powder in the cracks. Clean everything up and put it back together. the lever might be stiff, but does it leak, if not don't mess with it. Be sure that when you replace the back that the valve is on on.
V

[ptm]

Look for posts (or info on the web) that describe using phosphoric acid - it removes the rust without hurting the metal and it's a lot faster than electrolysis. I did it on mine and it came out great.

Unless the tank is badly rusted and a lot of metal has been eaten away, I wouldn't go the route of lining the tank with POR or Kream. Just don't let the bike sit for long periods without a full tank of gas.