How Do I Troubleshoot Water Pumps in Nissan Maximas?

A water pump is the component that pushes the coolant through the engine and back into the radiator to cool it off. If a water pump begins to go bad, it can cause your Nissan Maxima to overheat. You will need to troubleshoot the water pump, though, to make certain that is the problem. The troubleshooting is relatively easy if you follow a few key steps and a couple of tips.

Instructions

1

Check the coolant level in the reservoir. If it is below full, top it off with coolant.

2

Start the vehicle and allow it to warm up. Make certain that the cooling fans are turning on and off. If they are not, have them repaired or replaced.

3

Turn the vehicle off and allow it to cool down. Connect a pressure tester by opening the radiator cap and screwing the proper adapter onto where the radiator cap was.

4

Pump up the pressure tester until it reaches about 16 PSI then check for any leaks coming from the passenger side of the engine. If you see no leaks, allow the tester to sit for a few moments.

5

Check the bottom passenger side of the engine for a leak. The reason behind checking there is because that is the location of the water pump; and if the bearing is bad, it will leak from the weep hole. The weep hole is designed to open up and slowly drip fluid to indicate when the bearing goes bad. Replacement is necessary when a bearing fails.

6

Check the flow of the coolant by opening the radiator and allowing the car to warm up.

7

Look through the top of the radiator: the coolant should flow towards the engine from the top of the radiator. If it is not flowing, this is a sign of a faulty water pump or thermostat.

8

Eliminate the thermostat, as a problem, by trying to squeeze the upper radiator hose. If it is hard to squeeze, there is a thermostat problem that needs to be repaired then rechecked. Wear gloves or use a cloth when squeezing the hose as it is hot. If the hose is soft, then either the water pump fins are broken, or they are spinning on the axle of the water pump. Water pump replacement is necessary when the fins fail.