Smear water-finding paste on the bottom of the dip rod and dip the tank. Where the paste touches water it changes colour; that height is the water dip. MDG 2024 asks the dealer to record the water dip daily and to report any water to the oil company at once.
Taking a water dip
- Wipe the bottom 10 to 15 cm of the rod dry.
- Spread a thin, even layer of water-finding paste on it.
- Lower the rod straight to the bottom and hold it there for the time the paste’s maker states, often 10 to 30 seconds.
- Lift it out and read where the colour changes.
What the MDG asks
- Every day: “Dealer to maintain record of water dip on daily basis which will form a part of the daily stock register. In case presence of water is detected, he should immediately report to the controlling company office” (clause 1.4.1 b).
- Every tanker: check each compartment for water with water-finding paste, and a paste suitable for ethanol-blended petrol (clause 1.2 vii).
- Water in a compartment: the quantity, including what was removed as water, is made up by filling to the correct level and recorded on the invoice (clause 1.2 xi).
Counting the litres
Water sinks to the bottom. The litres up to the water dip are water; the rest is fuel. The dip to litres calculator takes the water dip and shows the fuel alone.
Figures here are for reference. Your oil company’s certified calibration chart, approved instruments and the Marketing Discipline Guidelines always prevail.
Questions
How does water get into a tank?
Through a loose dip pipe or fill cap in the rain, a leak in the tank or its pipes, condensation, or with a delivery. Any water is a reason to find the cause.
Why is water worse with ethanol-blended petrol?
Ethanol mixes with water. Enough water pulls the ethanol out of the petrol into a separate layer at the bottom, a phase separation. The petrol above loses octane and the layer at the bottom is useless. The MDG asks for a paste suitable for ethanol-blended petrol.
Should I take water off the stock?
Yes. Litres up to the water dip are not fuel. Type the water dip in the dip to litres calculator and it takes them off.