cleaning up rust in petrol tank

[vwnate1]

As mentioned Oxalic or Phosphoric acid diluted with tap water and sloshed around inside the tank will do the trick easily and leave you with clean shiny metal again .

A hand full of pea gravel, sheet metal screws or flat washers (the cheapo stamped kind as they have sharp edges) , I use a couple packages of BB's, pour them in along with about 1/2 the tank's capacity of the dilute mix and shake the beegeebers out of it, let sit then shake some more, repeat as much as your arms will handle then drain into a large holding container, using a BIG funnel lined with felt or other cloth to catch and separate most of the rust / dirt / etc. particles, look in the tank and re fill with the strained solution and shake some more until there's zero rust left .

Save the strained solution as you can use it to clean most any ferrous , copper or brass parts, DO NOT USE ON ALLOY OR CARBYS ! .

YOU will do a better job than any shop because YOU CARE and so won't rush the job, like most old vehicle repairs, taking the time to make it 'Just So' is important and not going to be done on the clock .

This method is cheap and easy .

All big box hardware stores sell Oxalic and phosphorus acid cheaply and it's not going tp burn your skin .

No need to buy distilled water etc.

Use the BLOW of any shop vac to help dry it faster, using phosphoric acid means no chance of flash rusting unlike vinegar .

Never, EVER vacuum a fuel tank no matter how clean you may think it is ! .

No need to coat it unless you're not going to use the car or if you discover pin holes .

If you're rich, look up your local "GAS TANK RE NEW" franchise, they can save paper thing worthless tanks but are NOT CHEAP .