In the intricate symphony of engine components, the water pump plays a crucial role in maintaining your vehicle’s cooling system. But what happens if you suspect this vital component has failed but leaves no visible signs of a leak?
A water pump can fail when no leak is evident. The working of a water pump is internal, so if the impeller, bearing, or shaft fails, there is no reason for you to find a leak. A Leak commonly occurs because the internal or external water pump seal has failed. The problem with a water pump that isn’t leaking and determining it is faulty is it’s quite a task to check, so you should be aware of the other symptoms of a failed water pump so that you can put two and two together.
Function of a water pump
The water pump’s job is to push coolant around the engine. Doing this regulates the temperatures inside the engine by moving the coolant into the radiator, where it is cooled and then back around the engine again.
A water pump works by spinning an internal impeller rotated by the timing belt or serpentine belt, which is driven by the speed of the crankshaft. The higher the engine revs, the faster the flow of coolant. Imagine there was no water pump, so nothing pumping the coolant around the engine; in that case, the coolant would not move as no forces are acting on it, trying to push it through the engine. The result would be the engine overheating as no moving coolant carries the heat for cooling. This is precisely the same scenario if a water pump stops working.
Can a water pump be bad and not leak?
A water pump can be faulty or fail without exhibiting any visible leaks. While a coolant leak around the water pump is a common sign of a problem, internal failures that do not necessarily result in external leaks can occur within the pump. Some examples of internal water pump failures include bearing wear, impeller damage, or a faulty seal.
These types of failures can cause issues such as poor coolant circulation, reduced cooling efficiency, or even complete water pump failure. Therefore, it’s essential to consider other symptoms.
One thing to also consider is just because you can’t see an obvious leak does not mean there isn’t one. Water pumps usually have a weep hole, which allows coolant to leak when the internal seal fails. The leak may only be small to start, i.e., just a few spots on the ground after sitting overnight, but a complete failure could occur the next time you drive. This highlights the importance of being aware of all the signs the water pump may have an issue.
Signs the water pump needs replacing
It’s essential to be aware of all the signs a water pump needs replacing, especially when there is no leak and you suspect a failure. The most common include:
- Coolant leakage around the water pump area.
- Overheating engine.
- Whining or squealing noise from the engine.
- Coolant reservoir frequently needs refilling.
- Engine temperature fluctuates abnormally.
- Steam coming from the radiator or engine bay.
- Rust or corrosion on the water pump housing.
- Visible wobbling or looseness in the water pump pulley.
- Coolant smells sweet or has an unusual odor.
- Timing belt shows signs of wear or damage.
How to check the water pump operation without removing it
To do a very basic water pump operation check, first, ensure the coolant level is filled to the correct level. Ensure the reservoir cap is present and secure. With the engine idling, you should see a steady flow of coolant being pumped into the coolant reservoir; this indicates coolant is passing through the radiator hoses.
If the reservoir is dirty and it’s tricky to see what’s going on, you can do this with the reservoir cap removed to see inside the tank; however, the engine must be cold to touch before removing the cap. Coolant spits violently and will erupt from the coolant reservoir if you remove the cap when the engine is hot.
How often should you change a water pump?
As a general guideline, water pumps should be replaced between 60,000 and 100,000 miles or 5 to 8 years. Water pumps are not like serviceable items such as the oil filter and spark plugs that need replacing regularly. One thing to be sure of is every car is different, and if there is a reason why the water pump needs to be replaced more often and on schedule, it will be indicated in the car owner’s manual/service schedule.
To check the condition of a water pump is very labor intensive and often requires the removal of the timing belt. For this reason, the water pump is not inspected, and unless there is a reason to change it earlier, it is replaced at the same time as the timing belt.
Is it ok to drive with a worn water pump?
You should avoid driving with a worn water pump at all costs. A worn water pump can lead to various problems that could be minor or completely catastrophic for an engine, and unfortunately, there is no way of knowing which you will get. There are a few reasons why driving with a worn water pump can be problematic:
- Engine overheating – A worn water pump will not be able to circulate coolant efficiently, which means there are no means to cool the engine. Overheating can occur and, depending on the damage, could mean an expensive rep bill.
- Coolant Leaks – A worn water pump can develop leaks, losing coolant. Insufficient coolant levels can cause overheating and potentially result in engine damage.
- Belt Damage – In some vehicles, the water pump is driven by a belt connected to the engine. A worn water pump can cause increased strain on the belt, leading to belt slippage, damage, or failure. In most engines, if the timing belt fails, the engine will be a total write-off.
A working water pump is vital in keeping engine temperature levels under control. So you should never drive if you suspect it has failed, especially without inspecting it. When there is no leak, the problem with a suspected water pump failure is that it will usually be an internal failure that you can’t see. To proceed, you must check the coolant flow, which is possible without removing the water pump. But that still won’t give you an idea of its condition, so it will probably need removing and replacing anyway!