You're just sitting in the parking lot with your pickup idling, waiting for your sister to return from a quick errand. Suddenly, you look at your dash display and see your engine temperature indicator rising slowly but steadily into the red level. Do you smell something burning?
Panicked, you shut down your vehicle and get out to take a look. Unfortunately, you don't dare touch the hood as you can already feel the blistering heat rising from the metal several inches away.
You just had your truck serviced last month. How did this happen?
The short answer is that there are many reasons an engine overheats, even those you meticulously maintain. Most importantly, however, you want to catch engine overheating issues as soon as possible and fix them immediately, as prolonged high engine temperatures can cause irreparable damage.
Over the many years we have supplied replacement parts to our customers for new and rebuilt diesel engines, our technicians have learned a thing or two about why engines overheat. To save you some research time, we compiled a list of the five most common reasons for engine overheating and how to avoid them.
1. Malfunctioning Thermostat
Your vehicle's thermostat opens and closes to control the coolant flow to and from the engine and the radiator and keeps your engine running at an optimal temperature. If the thermostat gets stuck in the 'Closed' position, the hot coolant can't get to the radiator to cool down. With no way to release the heat, the engine will eventually overheat.
The best way to keep your thermostat working correctly is to test it regularly. First, locate the thermostat in your engine. You can usually find it at the upper end of your radiator hose. Second, start your car and place your hand (you might want to use a towel to keep from burning yourself) on the upper radiator hose. Be careful to keep your fingers away from the engine block and the radiator fan.
If the thermostat is working correctly, the hose will feel cool until the engine heats up to about 185 degrees or after about five to ten minutes of run time. Then you should feel a sudden rush of intense heat as the thermostat opens to allow the hot coolant to travel to the radiator. If the hose feels hot right when you start the engine or stays cool after your vehicle has reached the temperature where the thermostat should open, you have a faulty thermostat.
2. Clogged Fuel Injectors
Diesel fuel injection parts, especially the nozzles, are sensitive components that regulate how the combustion chamber receives fuel to power the engine. If the injectors become clogged with debris, they can't deliver the fuel effectively, and the engine will have to work harder than usual to provide the same power. This can easily lead to your engine overheating.
A great way to keep your diesel injectors clean is to use a fuel cleaner additive once or twice a month and have your fuel system professionally serviced about every 45,000 miles (or less if you do a lot of heavy hauling).
3. Low or No Coolant
Coolant represents the lifeblood of your engine's climate control system. Often when your engine overheats, you don't have to look any further than your coolant. If it is low, empty, or contaminated with rust, your car's engine will have no way to cool down.
It's a good idea to pop the hood every few months and look at your coolant level to ensure it doesn't sink below the minimum line on the tank. If you suspect engine cooling issues, you can also invest in a coolant test kit to see if it's time to flush your radiator.
Vehicle manufacturers may differ widely on their recommendations for when to check your coolant. Still, auto enthusiasts generally agree that you should get your coolant replaced or at least looked at every 50,000 miles or so. That is because coolant can become acidic and cause corrosion in the coolant system, leading to overheating and expensive repairs.
4. Cooling System Air Pockets
Trapped air in your cooling system can prevent your engine thermostat from working as it should by blocking your temperature sensors. And as we stated above, if your thermostat isn't working correctly, your engine can't cool properly.
Many things can cause air pockets, including a leaky radiator hose, broken head gasket, or malfunctioning radiator cap. One of the most common reasons stems from incorrectly flushing your cooling system. It's critical to pay attention to your vehicle manufacturer's refilling instructions and bleed out any remaining air pockets before restarting the engine.
Check often for leaks underneath your car or truck, and monitor cooling components for cracks and breaks. Another sign you may have trapped air in your coolant system is when your car heater stops working, so it's also essential to pay attention to your interior climate functions.
5. Water Pump Failure
Your water pump plays an essential role in your engine cooling process in that it serves to circulate the coolant around the engine. If the pump seals are worn down or broken, you may experience a coolant leak under your vehicle, meaning there will be less coolant in your system to keep your engine temperature down.
Generally, water pumps fail due to years of wear and tear. You can extend the life of your pump by using the manufacturer-recommended coolant and holding to a regular service schedule.
For more information on how to keep your diesel engine in great shape and on the road, stop by www.goldfarbinc.com and chat with one of our diesel parts experts.
Infographic
Do you know why your vehicle’s engine temperature is rising to the red level? Your engine might be overheating. But why? There are several possible explanations for this and professionals have listed five of them. Knowing how to spot the issue and how to fix it will help you deal with the situation.
