Portable diesel refuelling units have become almost a standard item on the back of utes across Australia. They are appealing not only for their convenience for onsite diesel refuelling all kinds of machinery but also for their simple operation.
However, there are a few things that owners out there may not know about their units.
RUNNING PUMP DRY
12 Volt diesel pumps are rotor and vane pumps and they don’t do very well running dry because of the fact that they rely on diesel to lubricate the pump. The rotor spinning rapidly heats up and causes more and more friction, putting strain on the motor until it eventually burns out. If your pump burns out due to running it dry, not only does it set you back on your job, but it isn’t covered by warranty either.
PROPER SIZE PUMP FOR THE JOB
Like with spraying, you need to pick the right pump for the job. If your filling up massive tanks, then a 40L/min pump is going to take forever and when it comes to refueling, time is money.
On the other hand, there is such a thing as too big. Or more specifically when your delivery and suction lines are too small or too long for your pump. Pre-made Rapid Spray diesel units are fitted with the correct size hoses already but if you are making your own unit or replacing your pump with something bigger, then hose diameter needs to be considered. As a rule of thumb, pumps up to 45L/min should be using ¾” delivery hose while pumps large (60L/min +) should pump through 1” hose. Any smaller and you risk burning out your pump as it is pushing more fuel out than the hose can handle. Hoses shouldn't be longer than 4-6m for a 40-45L/min pump or 6-8m for a 60-80L/min pump. If you are considering extending your hose length, think about increasing the diameter to reduce the strain on the pump.
WHEN 12V JUST WON’T CUT IT
There are some contractors out there that are pumping out thousands of litres every day. As most 12 volt diesel pumps only having a working cycle of 30 mins and are designed for intermittent use, these poor little pumps aren’t going to be able to handle that kind of punishment over an extended period. It’s time to go bigger.