Symptoms of a Bad Water Pump: How to Fix it?

For your engine to run at a standard, designated temperature, it must have a constant coolant flow to the engine block. The water pump is the main component designed along with other cooling systems to ensure a consistent flow of coolant to the engine block. If the water pump work as it’s designated to, your engine will have an average temperature, run smoothly, and travel as far as you want it to. When the water pump begins to wear out or fails, it will cause catastrophic damages to other parts of the engine system.

Therefore, knowing the symptoms of a bad water pump is one of the keys to preventing a complete engine breakdown resulting from a bad water pump.

This article is a power-packed explanation of bad water pump symptoms and how a water pump works. You will also learn how to tell if the water pump is pumping.

How does a water pump work?

For an engine to run efficiently, it must quickly reach its operating temperature and maintain it at a constant level. The cooling system components that allow this to happen are the cooler, coolant, lines, thermostat, and water pump. Nowadays, the most commonly featured water pump is the mechanical water pump. They are closely linked to the engine system.

As the engine pulley spins, the drive belt pulley spins as well, allowing the axles to turn at the center. The axles on the center of the water pumps are linked together with many vanes that rotate the axles. This process creates suction and draws coolant from the radiator. Once the water gets to the pump, it gets pushed to the outlet pump walls via vanes generating force in the water pump inertia. It opens a drain and export coolant to the engine block, and to the cylinder head, back to the radiator to continue the process.

Symptoms of a bad water pump

You should note that water pumps, just like other engine components, wear out over time. Few factors can cause your water pump to fail. So, what causes a water pump to go bad? A water pump can go bad due to;

Bad/wrong coolant. It means that using incompatible or contaminated coolant can create corrosion in the water pump.

improperly installed/worn out belt. A misaligned belt or too tightened belt can cause the water pump to stop functioning optimally.

Low Coolant. A water pump running low or dry due to leaks will lose the lubricate needed to keep the seals in working order. If the seals overheat, it’ll go bad and cause more leaks.

water pump failure causes

Anytime you notice any of the following symptoms, you have to inspect your water pump quickly.

Coolant leak at the front of your car: The water pump is manufactured to function with gaskets and seals to ensure steady and adequate flow of coolant travels from the radiator to the engine block. So, if these seals and gaskets shrinks, crack, wear out, or break entirely, there will be coolant leak from underneath the water pump.  If you notice a leak of coolant that is red, orange, green, or pink in color, ensure you where the leak comes from or contact a professional mechanic to do a thorough diagnosis. Most often than not, it is a dripping coolant that you should replace before it causes severe engine problems?

Loosen or Noisy water pump pulley: if you start noticing a high pitched sound in front of your car from time to time, you might have a loosen belt that generates a harmonic whining or buzzing sound as it turns. The loose belt can result from a loosened water pump pulley or a worn-out bearing that operates the water pump. When the bearing inside the pump starts wearing out or goes bad entirely, it has to be replaced.

If you notice a buzzing or whining sound in front of your car while idling or driving, ensure you inspect your water pump or contact a professional mechanic for a proper diagnosis.

Overheating Engine: If the water pump goes bad entirely, it will lose the power to transport coolant through the engine block and the head cylinder. This can cause overheating, and if not given timely attention, it will cause catastrophic engine damage like engine knocking, burnt pistons, burnt head gasket, or cracked cylinder head.

If you find that the temperature gauge on the dashboard is rising, it’s surely that something is wrong with your cooling system, which is likely to be antifreeze leaking or a faulty water pump. You want to inspect your cooling system or contact a professional mechanic for thorough checks.

Deposit builds, Rust, and corrosion of the water pump: Over time, there will be a buildup of different minerals in the water pump due to gradual leaks. Inspect the water pump surface, you may notice rust a non-compatible coolant mixture, contaminated coolant, or radiator cap leak. Pouring the wrong coolant in your car will the normal process of the engine coolant. In addition to these symptoms, there may be small holes due to cavitation or corrosion.

If you notice these symptoms, you should follow the steps below and replace your water pump or contact a professional mechanic for proper diagnosis and fixes.

Steam coming from the front of your engine: Finally, if steam is coming from the front of your car while idling or driving, it tells your engine is very high in temperature which can also translate to an engine overheat. As explained above, it must reach its normal operating temperature quickly and maintain this constant flow for an engine to run efficiently.

If you notice steam under your hood while driving, you should stop your car at a safe place and inspect where the steam is coming from or contact a professional mechanic. It is a bad idea to drive an Overheating engine.

How to fix water pump leak

Fixing or replacing a water pump leak may be very difficult on some cars while on other cars, it can be a relatively easy job. If your engine runs on a timing belt, the water pump will likely be belt-driven, so replacing the water pump will require losing many components, including the timing belt. If this implies on your car, you have to contact a professional mechanic to replace your water pump. Kindly note that this guide will only be helpful if replacing your water pump does not require removing your timing belt.

This guide’s whole point is to show that you can replace the water at home and save hundreds of dollars. You are not going to do anything crazy. You don’t have to jack the car up. This is an effortless job, and you are using some standard tools.

Tools Needed:

  • A wrench
  • A Ratchet
  • Socket sets
  • Thread locker
  • Flathead screwdriver
  • Plastic gasket scraper

Other things Needed:

  • Water pump
  • Water pump gasket
  • Coolant
  • Drain pan
  • No-spill funnel

Now, you must use the correct coolant. Otherwise, you will damage your engine. Grab your vehicle owner’s manual and check for the specific coolant that your car uses. You can also check the coolant label, and its uses to show the cars that the coolant can be used on.

Step 1: Park your Car: Park your car on a strong, level floor, and engage the hand brakes.

Step 2: Allow the car to cool: you want to make sure that your car is cool. When systems are always pressurized when the vehicle is hot, you don’t want the hot coolant to come out and shoot at you when you remove the water pump.

Step 3: Remove the battery terminal cables: To get access to the water pump and perform a safety job, you have to remove the battery terminal cables.

Step 4: Remove the water pump belt: you need to remove the water pump belt because it wraps around the water pump pulley. Grab your spanner and get it on the drive belt tensioner and pull down to release the tension on the belt so you can easily get the belt out of the pulley.

Step 5: Drain your entire cooling system: place your drain pan under your radiator and remove the outlet hose and your radiator to drain out and flush your coolant.

Step 6: Unbolt the water pump bolts: you have to remove the bolts holding your water pump by breaking it free with your wrench. water pump bolts could be in different sizes, so you have to remove the bolts and place on the same holes on the new water pump. You have to do this one at a time in order to track where comes from. This will make installing the new water pump a lot easier.  Make you don’t see coolants coming from the thread holes. Because if you see coolants you have to add some thread locker on the bolts while reinstalling them.

Step 7: Pop off the water pump: After losing the bolts, you have to pop off the water pump.

Step 8: Clean the mounting Surface: Before you go on with mounting the new water pump, you have to clean the old gasket and sealant debris on the mounting surface.  To do this, you should grab your plastic gasket scraper and scrape off the old gasket debris. I do not recommend using a metal gasket scrapper, it can scratch the surface and cause a leak. If you’re having a hard time removing the gasket debris, applying a little bit of brake cleaner will help remove it easily.

Grab your smooth sandpaper and do a final cleaning on the mounting Surface so that when you mount the new water pump, you won’t have any leaks from the surface. Now, grab your clean rag and clean the surface and inside the water pump housing If any debris fell inside, you won’t want that to circulate to the engine.

Step 9: Mount the gasket on the water pump. Grab two water pump longer bolts and fix them on the water pump, place your gasket on it and apply a little gasket maker. You want to make sure that you’re using a gasket marker that is compatible with coolant, else the gasket is going to wear off and you’ll have a coolant leak.

Step 10: Mount the water pump.  Apply water thread locker on the bolts before mounting the water pump.

Step 11: Tighten the water pump bolts. You can now go ahead hand-tighten the first two bolts to hold the gasket and water pump in place. Hand-tighten the other bolts and get them ready for torquing down. It is important that you torque them down in a Crips-cross pattern.

Step 12: Reinstall the drive belt. Now is a pretty time to replace your drive belt if it is old or has some cracks on it. You have to fix back the drive belt just the same way you removed it. You want to make sure that the belt is centered on the pulleys and not misaligned.

Step 13: Fix back the battery terminal. You have to fix back the battery terminal and torque them down.

Step 14: Refill your coolant. Remove your coolant reservoir cap and refill it. You want to make sure there is coolant on your engine before starting it, if not, you will run your water pump dry and damage it.  You can use a spill-proof funnel to refill the coolant.  This will help remove any air trapped in the system. For a visual presentation on how to do this, watch this video.

Frequently Asked Questions (FAQs)

What does a bad water pump sound like?

What does a bad water pump sound like? Often, the problems that happen with the water pump result from worn-out bearing inside the water pump pulley and not the pulley itself. When the bearing starts going bad, it causes a grinding, whining, or buzzing sound in front of your car.

When should I replace the water pump?

Water pumps should last the life of a timing belt. The water pump can last up to 70,000 – 90,0000 miles. If your water pump has covered 70,000 – 90,000 miles, it is ideal for replacing it when doing extensive work that requires taking off the timing belt.

Should you replace the thermostat when replacing the water pump?

The thermostat may have encountered a lot of issues due to the bad water pump. So, the thermostat should be replaced when replacing the water pump, especially if the thermostat has not been replaced for a very long time.

Can a leaking water pump cause rough idle?

Can a bad water pump cause rough idle? Yes. Due to the effects of a bad or damaged water pump like engine Overheating and leaking coolant, your engine will experience rough idle.

How expensive is it to replace the water pump?

The cost of replacing a water pump depends on your car make, model, year, and how difficult it will take to replace your water pump. On average, you can spend around $250 to $700. The water pump’s actual cost should be $50 – $100 while the service fee should be around $200 – $600.

How do I know if my water pump is working?

Your water pump might be working fine if you do not notice any of the following signs of a bad water pump;

  • Coolant leak at the front of your car.
  • Steaming coming under your hood.
  • Engine Overheating.
  • Loosen or Noisy water pump pulley.

Final Thought

You must have known water pump failure causes, symptoms of a bad water pump, and how to replace a bad or failing water pump.

These symptoms will not appear immediately after your water pump starts going bad, so you have to ensure you fix or contact a professional mechanic once you notice any of the symptoms above.

Osuagwu Solomon

Osuagwu Solomon is a seasoned automotive technician for the past 9 years, and a technical writer. He loves writing about auto professional repair guides, DIY repair guides, and buyer’s guide. After spending six years in the automotive workshop, he decided to impact his knowledge to people aside his domain, and he has achieved this by centering his Automotive writing skills on REPAIRS.

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