Diverting Dust from Your RV Fuel Tank

If you've ever visited an Outback roadhouse, you may have come across some fuel bowsers that have fine powdery Outback red dust sticking to fittings, pipes and nozzles. When this dust is mixed with a bit of excess fuel or moisture, it can all resemble sludgy red mud. You may even have found that your vehicle's fuel cap area has had a similar appearance. The challenge here is not to let any of this muck end up in your fuel system.

But that's not all. Adding to this dilemma is the condition of the fuel inside the roadhouse storage tanks, fuel lines, and whatever filtration system they may be using. Underground storage tanks can become more susceptible after big rains and flooding – at which point it's possible that water can get into the tanks. And it could just find its way into your vehicle's tank if it's not filtered out.

Problems can also occur if these underground tanks are left empty. All the contaminants sit at the bottom of the tank and get stirred up the minute the tank gets filled with new fuel. If you just happen to be the next person to pump fuel out of it, you're really placing a lot of trust in the roadhouse filters – thinking they're going to collect all the gunk. If it somehow bypasses their filter system, then it might just end up in your tank, unless you have taken some precautions.

Aside from this scenario, you could be the type who likes to carry a back-up fuel supply in something like jerry cans. These are usually stored outside of the vehicle, where they can get exposed to a dusty and perhaps wet environment. This is just another instance where you'll need to take steps when decanting from them and transferring your spare fuel into your vehicle.

 The Dangers of Contaminated Fuel in Your RV

So what happens if you don't take steps to prevent muck from getting into your fuel system? Well, it's your vehicle's fuel filtration system that's your only line of defence. And while you'll find things will work for a while, you can expect the fuel system to eventually clog. You'll also likely experience the dreaded flashing engine light that's indicating a problem while your vehicle's engine begins to cough and splutter. After stopping the vehicle and running an eye over the vehicle's owner's manual, the last thing anyone wants to read is something along the lines of '… stop … do not run the engine… contaminated fuel is suspected… contact your nearest dealer immediately'. And here you are on some remote Outback dirt track without mobile reception. Ouch!

Driving with contaminated fuel means you run the risk of costly and severe engine damage down the track. For this reason, it's advisable to always carry a couple of spare fuel filters for Outback travel. So why a couple? We believe it should be a couple because if the fuel in your tank is contaminated, having multiple filters means you're able to change them over progressively when they clog up … all while continuing to use the fuel during travel. We're strong advocates for knowing how to change a fuel filter as well, but particularly when it comes to Outback remote travel. Don't let the day you take on contaminated fuel be your first attempt to change the fuel filter!

Clean v clogged filter

Filtering Funnels for Clean RV Fuel

They say prevention is better than cure, and this is where something like a good filtering funnel comes in handy. They've been designed to filter the fuel before it enters your tank. Although we're not talking about just any kind of filtering funnel in this instance. The type of filter you need is something that's capable of filtering out water and other fine foreign contaminants before they enter your vehicle's fuel tank. And at the same time, they need to filter hydrocarbons such as diesel and petrol. You could be thinking, "What do we mean by the term 'contaminant'?" 

Dirt and water that's been allowed to sit in stored fuel for a long period can often lead to microbial growth. This growth becomes very corrosive and forms electrolysis, which then leads to rust. At this point, there's a high risk of engine failure once these contaminants get into your fuel system.

The type of filtering funnel we take on Outback trips is oddly enough called a 'Mr Funnel'. These funnels come in a range of models and differ in their capacities and flow rates. The F3C 50 Micron model is the one we use – it's a plastic funnel that's Teflon-coated and fitted with a fast-flowing, inbuilt, in-line vertical style non-replaceable fluoropolymer-coated stainless steel mesh filter. 

Using these types of filtering funnels is very straightforward. Simply pass the fuel through the funnel as you would if using any other funnel; but you'll find the filtered fuel is the only thing that exits the funnel. What makes these particular funnels unique is the lower section that sits below the filter and acts like a sump. It's here where you'll see any water and debris that's been collected. We always use a Mr Funnel when topping up our tanks from jerry cans or filling up at remote roadhouses. We'll initially add about two litres of fuel to the vehicle before taking a quick look at the Mr Funnel sump for any contaminants. We'll then go ahead and continue to fill up completely if it's all clear. These funnels are a simple solution … they're worth their weight in gold, and great insurance for anyone who likes to venture beyond the city limits.

Mr Funnel in action.

Top RV Fuel Maintenance Tips

- Pack a good pair of fuel-resistant gloves to use while travelling to help keep your hands clean when dealing with fuel.

- Using a blower and some clean rags, clean all access points before opening, i.e. fuel caps, jerry cans; and when handling fuel bowsers, etc. 

- Aim to store your Mr Funnel, your gloves and some clean rags in a dust-free carry bag.

- Try using a transfer pump or even a siphon hose when decanting from a heavy jerry can, to help prevent a back injury.

- Avoid refuelling when a tanker is pumping fuel into the underground tanks, where possible.

- For more information on Mr Funnel, visit mrfunnelaustralia.com.au

More safety tips

For more RV safety tips about travelling off-grid and around Australia, check out rvSafe.

Category: Features
Written: Wed 02 July 2025
Printed: July, 2025
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