Water Pump Failures: Causes & Fixes

Without a properly functioning water pump, there will be no cooling in your vehicle, which will cause your entire engine to overheat and fail. Here are some of the most common water pump failures, their causes, and how to fix them.

Shaft Breakage

Your bearing is the part of your water pump where the impeller is allowed continual rotation to keep the system running. The shaft that connects your impeller to your bearing can cause the system to fail if it becomes damaged, because the impeller will no longer receive mechanical support from the bearing.

This type of break typically occurs at the top of the shaft, near the bearing, resulting in a clean fracture.

What Was The Cause of Such a Failure?

Bearing overload is the culprit in this type of failure. If at any point your bearing was overloaded with excessive vibration or imbalance, the shaft will become damaged because it cannot handle the additional pressure. If there is a blue discoloration present on your shaft, you'll know that the overload was gradual, with heat slowly building up until it became too much for the shaft and resulting in a breakage. The heat build-up would be a direct result of excessive imbalance in your pump's system.

If there is no blue discoloration, then the fracture happened quickly due to rapid engine acceleration from excessive vibration or imbalance.

How Do You Fix It?

The best way to fix the problem is to hire a professional. The mechanic will come out, dissemble your water pump and assess the damage by checking the pulleys in your system. If the pulleys appear to be fatigued, he will replace them before continuing on to review your pump's belts and fan. If the tension in your belts is not tight enough, your mechanic may need to also replace these. Same for if the fan is bent or damaged in any way. All of these parts play an integral part in controlling the vibration and balance of your water pump.

Seal Leakage from a Dirty System

Your seal is one of the most important parts of your water pump because it protects the bearing from coolant and other contaminates that may get into your system. Over time, your seal will need to be replaced because it comes in contact with coolants and contaminates regularly. The only way to avoid this is to maintain a clean system by regularly replacing coolant. A leak in the seal will cause rust to form on your seal and likely begin to contaminate other parts of your pump, causing them to fail as well.

What Was The Cause of Such a Failure?

A dirty system causes your seal to wear much faster than a clean system because of the excessive amount of contaminates present. If your system is not properly pressurized, air will enter the seal and build up more rust. In most cases, it is contaminated water that does the trick, damaging the seal and completely ruining your water pump.

How Do You Fix It?

You'll need a new water pump installed and a complete flush of your contaminated system. This means hiring a professional to run the flush, install the new pump, check your system pressure and ensure that the system is getting the right mixture of coolant. If the issue is with your water, you may also be advised to use distilled water to avoid future fates.