It’s a 4×4 driver’s worst nightmare – fire. With winter drives being a popular way to view game concentrated around water holes, fire risk from smouldering grass under your vehicle is something every off-roader needs to be aware of. We took a look at why vehicles burn, where you should look in specific vehicles and which vehicles are especially prone to picking up grass. To read our in-depth article, make sure you grab hold of issue 101 of Leisure Wheels magazine, on sale now!
THE VIDEO: We promised you a video of the Hattingh and Le Roux families vehicles on fire, and we’re working hard to get it for you – watch this space or sign up for our newsletter, and be the first to know when it goes live!
Until then, read our experts’ tips below, and comment with your thoughts on the dangers of grass.
What do the experts say?
Leisure Wheels columnist Francois Rossouw says there are specific danger areas, and ways of dealing with them. Two major culprits in the vehicle itself are cross members and sealing compounds.
The so-called cross-members — support structures which criss-cross under the car and form part of the chassis – intersect with the exhaust system. Grass collects there, and the heat from the exhaust system can set it alight.
Rossouw advises off-roaders to either buy asbestos exhaust bandaging, or move the whole system.
The bandaging can be bought at most DIY and auto-shops, and is wrapped around the entire exhaust system, fixed in place with wire or metal straps.
Many game rangers choose to move the exhaust system completely, due to the risk of veld fires. You’ll notice that game vehicles’ outlets are often far off the ground, often expelling gasses at the top of the vehicle.
While “die 4×4 ou” has never had a vehicle destroyed by fire with him around, he has experienced problems with a sealing compound used on the undercarriage of some vehicles.
“This sealing compound, which is used as a noise insulator on the underbody as well as inside the car under carpeting, seems to be quite flammable. I’ve seen how it starts burning, and that compound was dripping off the car.
“The grass was just a lighter, or catalyst, and had burnt out by this point, yet there were still parts of the vehicles starting to burn.”
Rossouw says that if manufacturers could make this compound from a safer substance, the chances of a vehicle on which it was used catching fire from trapped grass would be much lower.
Once that compound catches fire, says Francois, “it’s over”. A vehicle can burn out within minutes.
Keep these tips in mind
Check for grass and small seeds around the exhaust pipes, prop-shaft, in areas which are greased, around and on top of your petrol tank (if possible), inside the exhaust outlet, in the grill and radiator area and on the inside of the wheels and the suspension system. Also check inside the engine bay, especially if you don’t have a grass protector fitted.
Don’t rush it. Use the time to take photographs, and stretch your legs – but this is one aspect of your trip on which you cannot take short cuts.
If you’re on a self-drive trip, set some kind of alarm as a reminder to stop.
Always have a fire extinguisher in your vehicle.
Remember that a heavily loaded vehicle’s ground clearance may be reduced slightly, and therefore be more of a risk. The extra load also means the engine works harder, and therefore heats up more quickly.
Petrol is flammable – obviously — but the point is that none of the guides we spoke to had heard of a diesel vehicle catching fire. Petrol fumes need a spark to ignite it, whereas diesel ignites under compression. That’s not to say you can carelessly plunge through grass in your dCi or D-4D. It just means that drivers of petrol-driven vehicles should be extra careful.
When you get home from a winter excursion (and trips to areas that haven’t had their rainfall yet), have your 4×4 lifted for a thorough cleaning. A pressure hose should do the trick. Don’t assume that your vehicle is safe just because nothing happened. Hattingh (who tells his own story of losing a vehicle to fire in our next issue of Leisure Wheels) reports helping a client who, after driving 700km of tar road back home after a hunting trip, experienced a fire on his Isuzu 280. The gearbox had been leaking oil, and grass got stuck in it. It took hours of long-distance cruising for the grass to heat up to the temperature that set it alight. Luckily, the client’s vehicle wasn’t damaged, but the incident serves as a warning to overlanders.