Removed my carb on the 383 for a rebuild and noticed a brownish "coating" in the float bowls that wipes right off with the finger. Rust sediment? Anything I can toss in the tank without dropping it to help break it down?

 

Not that I'm aware of, put a good fuel filter on it. You will probably be replacing the tank.

 

I agree with Iowan.....
I would add 3 inline filters, 2-Clear filters on the fuel tank side, then you can just delete them as they pick up the rust, but you will save having to rebuild the carb again...
I also would ad in some seafoam to the gas tank. 1 can with every fill up...
https://seafoamworks.com/product/sea...fuel-additive/

 

You may want to do a couple of clear filters between the frame rail and fuel pump, in case the hard lines are rusting out. Had this happen on my 83 CJ the ethanol tore up the rubber and mild steel lines. Tank is 20 gal plastic, so I know it was not the tank. In tank pump also had some rust. If you can find it, run non ethanol fuel along with the sea foam. If there is water in the bottom of the tank, this will help clear it out. Acetone or 99% Isopropal also works by binding with the water and burning it, also helps with shellac, be careful on the amount as it can cause other issues.
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