How often should you dip your fuel tank?

Dipping your Fuel Storage Tank is Essential

dipping a fuel tank. fuel dipstick

If you’re a fuel supplier, or your business relies on your vehicles, then you can’t afford to take chances with fuel quality.

Maintaining your fuel and your fuel tanks is critical -testing fuel quality regularly will save your business tens of thousands of dollars and keep your cash flowing in the right direction.

F.E.S. TANKS services clients from farmers to major retailers storing up to 1.5 million litres of fuel each day. We’ve distilled the top points from our clients to give you the low-down on how often you should test and why.


Why should I dip my fuel tank?

1. Regular dipping ensures you can detect fuel loss early and take action to stop it.

Dipping your fuel tanks is good business practice because it reconciles the fuel left in your tank with what has been sold out of the bowser, and will quickly pick up any discrepancies. This means you know quickly if you are losing fuel through leakage, theft or poorly calibrated dispensing systems.

A leaking fuel tank not only hits your business where it hurts by reducing your saleable supply – if left undetected it can mean serious safety issues and six-figure fines from the EPA, not to mention a hefty clean-up bill.

Keeping a close watch on the levels in your fuel storage tanks will also keep your fuel in good condition and protect your customers.

Over time, silt builds up in the bottom of all underground storage tanks. A common problem with old or low volume tanks is that when a truck is unloading product and pumping into the tank and a customer is simultaneously using a bowser, this silt is stirred up and makes its way into the customer’s vehicle, causing blocked filters and potentially more serious issues.

Many older underground tanks also have suction lines that run close to the bottom of the tank, increasing the chance of sucking water or silt into vehicles and causing damage. Maintaining proper fuel levels can minimise the risk and keep your fuel in top condition.

2. Fuel dipping can detect water and pollutants in your fuel storage tanks.

If water does get into your fuel supply it can do serious damage to a vehicle, and if you’re a fuel retailer or wholesaler a bad batch can destroy your reputation and leave you to pay significant reparations.

Water contamination in fuel tanks can cause anything from intermittent power loss to engine failure, and the damage done can range from blown injectors to cracked components and cost thousands of dollars to fix. More than that, if you’re a retailer one bad batch can do untold damage to your future sales potential.

Water in fuel also creates an ideal breeding environment for microbes which can degrade your fuel and cause phase separation, particulate contamination and tank damage due to acids produced by the microbes.

So what will I check for when I dip my fuel tank?

Essentially, when you dip you’ll be looking to ensure the fuel that is missing from your tank is equal to the amount you’ve distributed from your bowser or point of sale system.

You can keep a record of your levels with a fuel management system – if you’re supplying your own fleet of vehicles, a good system will give you an early warning if a vehicle is not performing well or needs servicing.

You should also test for water by using a water finding paste on your dip stick. Drain any excess water immediately to keep your fuel fresh and reduce the potential for microbial contamination.

Finally, using a fuel sample test kit is good practice to ensure your fuel is free from microbes and particulates.

How often should I dip?

If you’re a commercial fuel supplier, best business practice is to dip your fuel tanks daily to check fuel levels and test for water contamination. Ideally you would also use a fuel sample test kit regularly and keep up regular inspections of and maintenance on your tanks and fittings.

If you only store a small amount of fuel and use it irregularly, you should always dip your tank and test for water before you fill up. If you store your fuel for long periods, for example for seasonal farm work, it’s worth taking a sample before you fill up machinery to avoid unplanned down time and lost productivity due to damage and equipment failures caused by water or particulates in your supply.

What if I discover a problem?

If you discover a leak in your tank or microbial contamination, F.E.S. TANKS can help you find the best solution for your situation.

If your fuel is contaminated your tank will need to be filled and dosed with a biocide which will help address the problem. Older tanks are more likely to have this issue due to wear and tear over time which allows water leaks, and to issues such as condensation.

If you’re losing fuel and your tank isn’t leaking, we can help address issues like fuel theft with a range of security cameras and fuel management systems.

If it’s time to replace your tanks, F.E.S. TANKS has a complete range of fuel storage systems for sale or hire to suit all fuel storage needs.

Contact our industry experts to find out the best fuel storage options for your business.

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  1. How many days each month are you legally required to dip your under ground tank in a service station in South Australia

    • We don’t believe there to be legislation as to how often you must dip. The biggest consequence of not dipping is if you spring a leak in your tank and you have failed to find this leak in reasonable time you will be seen to be negligent by the authorities. So therefore if your tank ruptures and you find the leak in good time you have less risk of being fined by EPA.

      Regular dips will also go along way to support maintenance records / logs i.e. evidence of regular human intervention etc.

  2. Can dipping a gas station tank detect if diesel has contaminated the gasoline?

  3. Where to buy this item?

  4. How long should i leave the dipstick in the tank when doing dip. I am asking because i have a wooden dip stick, if i leave it too long will it soak up higher the dip stick or not. Dip stick is supplied by fuel service providers and calibrated by them

  5. Dear Sir/Madam

    At the company I work for we have 2200 ltr diesel tank and we only keep/store a maximum of 1500 ltr for a fleet of our forklifts.

    Every time we top it up to it’s full capacity i.e. 2200 we start to experience a huge variance of about 150-200ltr.

    What could be the main course of this problem?

    I doubt it could be theft because we have CCTV (cameras) installed to record and monitor the movement around the diesel tank.

    We top up 1500 ltr every 7 days but our tank dispenser doesn’t have the vapour recovery systems.

    Please advise.

    Kind regards

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