citric acid

[vmaximus]

I need to clear some light rusting from inside of a small petrol tank and am going to use citric acid but what ratio do you need to mix the citric crystals. Thanks. Pud.

 

[awemawson]

It's not critical. A 1/2 pint mug full in a gallon of warm water is fine.

 

[The_Yellow_Ardvark]

1 tablespoon to 1ltr of water.

 

[vmaximus]

Thanks chaps for your quick reply's.

 

[bigegg]

I just chuck some in a cup of boiling water until it won't dissolve any more.

 

[pedrobedro]

I work on the plenty to one ratio for anything like this

 

[Wallace]

A 5% mix (19:1Water:Citric) up to 20% (4:1 Water:Citric). Much the same instructions as another similar product.

 

[Screwdriver]

I just chuck some in a cup of boiling water until it won't dissolve any more.

This is the best way to ensure you are dissolving all of your acid. The reaction is typical in that it responds very positively to temperature. I always dissolve mine in hot water before diluting to taste. The actual concentration is less critical since you an make up for a weak solution just by waiting longer.

The key is temperature though and if your acid is a lot colder, you'll be waiting a lot longer.

 

[Turbo]

Add a handful of s/s nuts or washers - they act as an abrasive if you shake the tank.