I changed my fuel filter this evening and this is what came out of it when I removed it.

Could this be the culprit for the brown sludge I have been finding in my AST? Could this be the reason why the coolant I recently flushed out of my system is dark brown?

I am assuming that the inside of my gas tank is rusting.

Please share thoughts & concerns regarding the matter... On top of the main fuel filter (which was a total pain in the *** to replace), I intend to install a second filter --- this brown mess can not be good for anything but disaster.

 

Here are pics

 

If you're getting this crap in your coolant too, you've got more problems than gunk in your fuel system.

 

There is no connection between the cooling system & the fuel system, other than both are present in the engine. They are, however, definitely isolated from each other.

It’s unusual to find rust in the fuel tank, but these cars getting up in the years. You read more & more about cars sitting for years with a blown engine under a tarp outside. Finally being sold & resurrected back to life.

Both the cooling system & fuel tank could get corrosion from lack of use & the elements.

I would flush & fill the cooling system & replace the thermostat. You can inspect the interior of the fuel tank from the fuel pump access panel in the trunk.

 

good advise, i would drain the fuel tank remove the fuel pump and have a look in the tank, 1 hour job max, then at least you know, dark brown coolant is a sign of coolant leak i speak from experiance