Depends on what's in there, and how much of it... Sediment/sand/dead gas varnish? I've cleaned a lot of that out several boat fuel tanks, using a mix of automatic transmission fluid, carb cleaner, and a box of 5,000 BB's, works well when you can hang the tank from a rope and tilt/slosh it around. Rust? You might try the above, but unless you are absolutely sure you can get it ALL out (behind baffles, sumps, etc), I'd lean towards a new tank, it can be cheaper/simpler in the long run. POR-15 is really amaznig stuff, don't know if they have anything for gas tanks, tho...
Getting the crap out is a problem. Last time I fixed my gas tank I installed a drain plug in a lower corner. That way I could get all the water out of it after I had fixed the leaks and for leak test. I also dropped a magnet inside to grab any lose metal. I then covered up the drain plug with a big blob of clear silicone just for safety sake.
I remember back in my Street Rod Days we use to drop the tank and pour in a sealer. You would slosh it around and pour out the excess. It would harden up and seal up pin holes and rust. It worked quite well back in the day. It's been a while but I think a company called "Midway" use to make it. I dont know if there around anymore.
I found something close.... http://www.prp-porstore.com/merchant.mvc?Screen=CTGY&Category_Code=TankSealers This should do it $7.00 1/2 pint
It doesn't have any rust and my clear inline filters don't go brown they stay clear. I do plug up filters every time I run it low though. The first time I plugged one it would barely run and now it just runs rough and my idle speed drops from 650 to 500 RPM. I am tired of replacing the filter every fill up. I know if I didn't run it low It would be less of a problem but I want this sediment or whatever it is gone. So steamcleaning or soapy water should work fine? Also should I run the regular filter in the carb aswell as the inline filter? Thanks for the suggestions, Sean.
No Rust? That's great! I'd hesitate to use water as a cleaner, it's not too good at cutting fuel sediments, kinda like mixing oil and water...and I'm not sure how you'd be able to reach every part inside there with a steam cleaner. Drop the tank, take out the sending unit, that should give you a big enough hole to see inside with a flashlight, or shine a light in the filler neck...Anyway, see if there are internal baffles, and if so, how big are the openings around the baffle-to-tank edges. If there are baffles, the openings should be big enough for BB's to pass. Mix up three quarts auto trans fluid, one quart carb cleaner, and a box of BB's, I think 5,000 come in a $4 box at Wal-Mart. Dump it all in, slosh it all around, might let it set for maybe a half hour, then slosh it some more. Dump it all out, you might have to get a magnet to chase down that last BB. Then put in a gallon or so of gasoline, slosh it around to cut the trans fluid, and drain it. That should leave you a nice clean gas tank. Make sure your fuel pickup and sock are clean, and your lines are clear, and you should be on your way.
Thanks, I am starting that now. Should I run a inline filter aswell as the carb one. Or just the inline?
I went with just an inline. But used the big can type. They are usualy on the shelf near the oil filters. Big silver can nipple end filter. I then removed my carb filter. It was dirty n e ways. I also put my filter before the fule pump. 2-3 inches before. I just used water to clean my tank. Worked well but your gonna kill some grass. I have also never seen worms jump out of the ground so fast as when water n gas mix gets on the ground. They jump out and get 2-3 inches of air. My tank was just rusty on the out side, clean n nice inside. I just used water to get the gas out and to leak check it as I fixed it.
I thought the fuel might spray differently into the carb without the internal one. So I only need the inline filter?
nope. It would not affect spray. The only thing that would do that is too much fuel psi. You can run both though if its clean. Mine wasn't so I ditched it.
Hey, glad to hear it!!! And my brother-in-law thought I'd never amount to anything... (Plus, now you've got 5,000 oily BB's you can use to slingshot at neighborhood cats, etc...) Have Fun!
