Water pump noises can be an indication that your vehicle’s water pump needs to be replaced. Replacing or fixing it is something you should not delay since water pump failure can cause overheating that can lead to a more serious problem such as a destroyed engine. While most of the modern vehicles are equipped with water pumps that last for a long time, they are also susceptible to wear and tear like any other parts of your vehicle. If you begin to notice water pump noises, it is best to take heed of your vehicle’s early warning signs and check your water pump before it is too late.
What does the water pump do?
Before trying to check and diagnose what causes the water pump noises in your vehicle, you need to understand how a water pump works to make it easier for you to distinguish what needs to be fixed or replaced.
The water pump of your vehicle is the one responsible for the cycle of taking the coolant from the radiator and moving it through the engine block, cylinder heads, heater core, hoses, and back to the radiator. It is the one that sees to it that the engine maintains a constant operating temperature regardless of the temperature or the weather outside. The water pump is needed to cool the water down since the water from the radiator heats up as it flows through the motor. It pumps the water back to the radiator where it can cool down that can keep the engine from overheating.
The water pump has seven basic components which are the housing, impeller, shaft, bearing, hub or pulley, seal, and mounting gasket. All these components work together and ensure that it works perfectly. Water pumps can usually move 7 gallons of coolant in a mile drive depending on the power of your engine. The faster the engine, the faster it pumps. With the amount of work the water pump does, it is understandable why it is prone to wear and tear and why one should be swift to fix or replace it once it starts to show early signs of failure such as water pump noises.
Different kinds of water pump noises and their causes.
There are different kinds of water pump noises you can hear and each one has different causes. To help you know and diagnose your water pump issues, here are some of its most common noises and what causes it.
Clicking or Squeaking Sounds
Worn or failing bearings of the water pump can create this sound since it is responsible for supporting the shaft that connects the impeller and the pulley. Worn bearings are no longer rotating smoothly and this creates the clicking or squeaking sounds. You can sometimes experience or hear this sound when your engine is idling. The noise becomes more audible after you shut off the engine and loosen the tensioner. You can try to listen for noises as you spin the pump using your hand. Noisy pump bearings should be replaced as soon as possible to prevent further damage to the other components of the water pump. You will have to disassemble the pump housing to access it if you need to replace it. Just remember to check your vehicle’s owner’s manual to know the right replacement part numbers of your bearings before purchasing a new one.
You can check if your water pump bearing is faulty and if it is the one causing the noise by using a long screwdriver or a rubber hose. To do this, you have to start your vehicle’s engine. Make sure that you won’t touch any of its moving parts as you open the hood. Once you’ve located the water pump, touch its housing using the tip of the screwdriver or the rubber hose. You can then listen for sounds coming from it by putting the other end of the screwdriver or rubber hose against your ear. A faulty bearing makes the rotation of the shaft rough and irregular.
Rattling sounds can be caused by a number of reasons. One of which is a broken or a bent impeller shaft. You can hear this sound when your engine is cold and stops as it begins to warm up. This happens because when the engine is warmed up, the coolant will start to flow through the water pump and this provides the needed lubrication to stop the rattling noise. When this happens, it is recommended that your water pump should be replaced to keep any metal shavings from contaminating your vehicle’s cooling system.
Worn belt tensioners can also cause a rattling sound. You might want to check your belt tensioner if it is loose or worn out. You can try to spin your pump and check if it rotates smoothly. You can also check your tensioner the same way, loosen the belt tension and check its play. Rattling sound can also be a sign that your bearing is about to fail.
Whining or Groaning Sounds
These kinds of sounds usually happen when you have a faulty water pump pulley. The pulley is driven by the serpentine belt or V belt and is responsible for rotating the water pump. It is also prone to wear and tear and rust contamination that causes its bolt holes to crack. If the pulley is broken or cracked, it tends to wobble as it turns creating a whining or groaning noise. Pulleys with V belts can also be damaged when the belt is too tight or if the belt used is not the correct size and if it is loose, it can also create groaning noises.
To check your pump pulley, you can try to shake it lightly using your hand. If you notice any signs of damage or movement, then you will have to replace your water pump. If you try to rotate it and it spins freely, that too is an indication that the pump needs a replacement. A good pulley spins smoothly and tight.
Symptoms of a failing water pump
Aside from water pump noises, there are also other symptoms that you will encounter if you have a failing water pump. Keep in mind that it is better to act on it and have it repaired or replaced immediately. It is always a wrong idea to wait for more signs and delay repairs and replacements.
- Temperature warning light is on. This means that your engine is overheating. If your water pump is not functioning as it’s supposed to, the water or coolant stops circulating through the engine. This in turn leads the engine’s temperature to rise quickly. You might notice a steam under the hood caused by the coolant boiling out from the radiator. Rising engine temperature can also be caused by a loose or a worn out impeller. The water pump impeller should also be firmly connected and attached to the shaft. If it is not, it can fall off stopping the flow of the coolant. Keep in mind that there are also other parts of the vehicle that can cause overheating such as a faulty radiator, cracked head gasket, and a stuck thermostat.
- Coolant is leaking. The water pump has a weep hole that is made to allow the coolant flow through it when the interior seal degrades. When this happens, the coolant bypasses the seal which leads to an external leaking. Worn and cracked water pump gaskets can also cause leaking since it allows the coolant to penetrate between the pump and the engine block. There are instances where you can just remove the water pump and replace the gasket to fix it but if your water pump is driven by a timing belt, most mechanics would recommend a water pump replacement. Remember that there are vehicles that are equipped with a plastic pan underneath the engine. This can conceal leaks and can give you the impression that the leak comes from a different location. It is better to check your coolant level regularly and remove the pans to see if there is a leak.
Additional tip. Coolants that are acidic and contaminated can be the leading cause of broken water pump gaskets, seals, and other internal components. Fresh coolants have buffers that control its pH level. That is why it is very important to maintain a regular schedule for coolant replacements. This will ensure that your coolant stays fresh with additives that help the water pump gasket and seals healthy. It also protects the working parts of the water pump and prevents corrosion and other contaminations.
How to conduct a water pump test?
When you notice the early signs of a failing water pump such as overheating and water pump noises, you can immediately do some simple checks or tests so you can determine what causes it. Here are some of the tests you can do at home.
- The Flow Test. This test is done to make sure that your water pump is working fine. To do this test, the engine needs to be cold. If you used your vehicle before starting this test, you will have to cool it down first. When it is cold, you can proceed to remove the radiator cap. When you’re sure that it is properly filled with coolant, leave the cap off and turn on the engine. The thermostat will open as the engine begins to warm up. You will know if it is open when the radiator hoses are hot. If it is, check the radiator and see if the coolant in there is flowing. In most cases, the coolant will look like it's spinning in the radiator. A clear indication that the water pump is faulty is when you see no movement of liquid in there. It means that the pump is no longer pumping. When doing this test, you need to be extra careful since the coolant expands as it heats up and it might spill. If it starts to boil and spray everywhere, stop the engine and leave the key in the ON position to allow the radiator fan to continue working, cooling down the coolant. If you’re sure that it has cooled down, reinstall the radiator cap and clean your vehicle’s front.
- The Squeeze Test. This test can also determine if you have a bad water pump. Make sure that you are wearing heat-resistant gloves to protect your hands. To start, turn on your vehicle’s engine. Wait until the engine achieves the normal operating temperature. When it does, squeeze the upper hose of the radiator as tightly as you can and release it. If you feel the surge of coolant being pumped through as you release the hose, then your water pump is working just fine.
- The Shake Test. This test is done to check if your water pump has bad or failing bearings. To do this, you will have to remove the fan belt that is driving your water pump. It won’t take much effort to remove it if your water pump is driven by a serpentine belt. But if it is driven by a timing belt, it might require some time to have it removed. Once you remove the fan belt successfully, hold the pulley firmly and shake it up and down and side to side. There should only be a little or no movement at all. If you can feel the pulley move, then it means that your bearings are failing and a water pump replacement has to be done soon.
Water pump plays an important role in your car’s overall safety operation. You should always be mindful of it and the early warning signs it gives when it is about to go bad or fail. Water pump noises are one of the symptoms. If you happen to hear it, you need to take action as soon as possible and get the right diagnosis to correct it. Delaying any maintenance, services, and repairs could lead to a more serious damage. Make it a habit to check your owner’s manual for the recommended schedules to prolong the life of your water pump as well as the other working parts of your vehicle.