How To Test A Car Water Pump: Steps And Tips!

There are two ways to know when a water pump is failing: You can check and fix it in advance, or you can simply wait for the engine to burn out. One of these two facts can make you solve the problems in the water pump in just 15 minutes and you would also be saving yourself a good amount of bills, the other will make you lose the water pump and cause damage to the engine. It is for this reason that you must learn how to test your car water pump and prevent more severe damage

Figuring out the issues with a water pump is so simple that just about anyone could do it, which is why if you’re in a car, and you’re afraid you’re driving with a bad pump and you don’t bother to fix the issues, you probably want your car stop working

How to test a car water pump

How to Check a Car's Water Pump
How to Check a Car’s Water Pump

It is convenient to test the devices in your car to avoid rapid deterioration in components, avoid future failures and improve the performance of the car. Read and learn how you can test an automotive water pump.

1. Listen for unusual sounds from the water pump.

If you hear a strange noise in the car, but you don’t know where it’s coming from, then take the tip of a long screwdriver and firmly apply some pressure to the water pump. Firmly press your ear into the round end of the handle, as if you were trying to put it on your head. The solid screwdriver will not pump sound concisely into the skull and your inner ear, allowing you to pinpoint the source of the sound.

2. Open the radiator cap and start the engine.

Open your radiator cap, start the engine and then bring it up to operating temperature. Look down at the open radiator cap at the water in the tank, and also at the upper radiator hose access if you can.

After the engine warms up, you should watch the water rush continuously into the radiator, try to notice if it is not dripping, especially at the moment when you rev ​​the engine a little. Dripping or lack of water flow could also reveal to you a faulty thermostatalthough in any case, something is not right.

3. Look at the steam emitted.

Notice the steam coming out of the top of the radiator hose. Slightly rev the engine and watch for steam coming off the top of the radiator hose or radiator cap without the water being rushed. If the thermostat is stuck halfway open, then it means the water pump is building pressure at the bottom of the thermostat and trying to force water through it.

That water is not going to get through, although an increase in outlet pressure could force the flow of pressurized water to rapidly decompress on the radiator side of the thermostat. This decompression could generate a jet of water vapor, something that a water pump that is defective but not sufficient would do. Therefore, the steam is the same as with a failed thermostat.

4. Liquid leak.

Establish whether or not you have any leaks around the water pump, as this is where failures usually start. Clean the area around the pump seal down to the water block and bottom of the well with detergent and water, then dry completely and thoroughly using compressed air or a towel.

Fill your hand with talcum powder and place it on, under and around the water pump. Some places are soaked in existing water or grease, however continue to apply the powder until you finally have a dry and even area. Start the engine and let it idle for a while so it can get up to temperature. Leaks can only occur under pressure, so heat is essential in this case.

5. Detect dark dots or streaks.

Look around the pump and spot streaks or dark spots in the powder. If the pump leaks or spills, the powder will tell you.. If, after 15 or 20 minutes of inactivity, there are no scratches or other obvious signs of a leak, then the leak – if any – is from somewhere else.

This does not mean that the water pump is in good condition, only that it does not have spills. For the engine, clean the hose and give it time to cool down and dry. Do not hit hot exhaust manifolds or electronic equipment with water.

6.Remove the tape and check the water pump shaft.

Hold the pulley with both hands, if possible, and try to move it back and forth, up and down, in and out, in all directions. Any water pump you use is going to have some play in the shaft, though if your pump moves more than 1/16th of an inch in either direction, then it’s time to change the water pump.

How to Check a Car's Water Pump
How to Check a Car’s Water Pump


In this way you will be able to test the water pump of your car, remember that there are elements that are very difficult to repair and the water pump is one of these devices, in most cases the water pump would be hopeless, and will require replacement.

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