Your engine can overheat at any point, but summer is notorious for frying 4x4s. Thankfully, overheating is something that can usually be fixed on the spot – you don’t have to call someone out to tow you away unless you’re very unlucky. So, what can you do to prevent a 4WD overheating, and what should you do if it does overheat?
Join us as we look at how to stop a 4x4 engine overheating and the main offenders when it comes to a 4x4 meltdown.
Check Your Radiator
If you’re experiencing 4WD overheating, it makes sense to check the main component of your vehicle’s cooling system first. The radiator cools down fluid after it’s done a circuit of the engine. Check yours for any signs of damage, including leaks, which can be patched with metal putty.
Also check the radiator’s fins, which can become clogged with all manner of things while you’re driving, such as dirt, mud and grass seeds. Bent or damaged fins may also affect cooling efficiency, but these can be carefully straightened out with pliers.
Check Your Radiator Cap
The radiator cap is an important part of any car’s cooling system, allowing coolant to circulate under pressure and thereby raising its boiling temperature. A higher boiling temperature means the coolant is more efficient at removing heat from your engine and thus helps prevent your vehicle from overheating.
The radiator’s cap is crucial to this cycle, as it helps to maintain the necessary pressure. A fault with the cap can cause your engine to overheat quickly. If your engine is running a bit too hot, pull over and give the radiator time to cool down. When you’re safely able to touch the cap, carefully remove it (the fluid inside may still be under pressure and squirt out, so keep your face well clear). Check the gasket on the underside of the cap – if it’s split, brittle or hard, it may be unable to seal properly and hold pressure. Carrying a spare cap will help you avoid 4WD overheating due to radiator cap issues.
Check Your Coolant
If you’re wondering how to stop a 4x4 engine overheating, check your coolant levels before setting off on your next road trip. While coolant has a higher boiling point and lower freezing point than water, it doesn’t displace heat as well. This means that adding water to your coolant may help stop your 4WD overheating.
You’ll have to use distilled water though, since tap water can rust the inside of your engine and cause corrosion within your 4x4’s cooling system. If you don’t have distilled water and it’s an emergency, you can temporarily use tap water. Just be sure to flush and refill the system as soon as you can.
Check Your Water Pump
The water pump - as the name implies - pumps coolant around the engine to prevent overheating. Since your pump relies on your 4x4's belt system, it's best to check your belts for any sign of damage. If they're torn or cracked, you should replace them (and while you're at it, get a spare for the future).
If the belts aren’t the issue but the pump is still playing up, you may need to take a closer look to figure out how to stop your car from overheating. Check for leaks around the pump housing, as this could be the cause of the problem. The effectiveness of your water pump comes down to cooling system maintenance, so be sure to use fresh coolant every couple of years (and keep it regularly topped up).
- Fans. As these draw air through the radiator, a malfunctioning fan could be causing engine overheating.
- Hoses. Make sure they aren’t cracked or brittle.
- Head gasket. Bubbles in your coolant, oil mixed in with cooling fluid, or slime under the oil cap indicate that your head gasket has blown. It’s time to get a new gasket fitted, but in the meantime, you can dry a tube of stop-leak.
- Engine and radiator for dirt. Either of these being covered in dirt or mud can cause your engine to overheat. Cleaning your engine bay between trips can help with this.
Remember: when your engine first shows signs of overheating (steam under the hood, your temperature gage in the red, or a strange smell coming from the engine area), one of the first things you should do is kill the air conditioning and turn up the heater. This will draw heat away from the engine for a bit, giving you enough time to find a safe place to pull over. From there, go over our list of problem points and save yourself a costly repair bill!