Crossover operation Nissan Murano second generation (Z51 body) requires careful attention to the cooling system, especially considering the high thermal loads on the series engine VQ35DE. The coolant in this car does not last forever: over time, it loses its anti-corrosion properties, which can lead to overheating and expensive repairs.
Many owners neglect routine maintenance, believing that the fluid is changed only when there is a leak. However, to preserve the life of the engine and thermostat timely replacement critical. In this article we will look at which antifreeze to choose, how to properly drain the old mixture and how to avoid air locks that often arise when servicing Nissan engines.
Choosing the Right Coolant for the Murano Z51
Cooling system Nissan Murano Z51 extremely sensitive to the chemical composition of the antifreeze used. The manufacturer strongly recommends using the original fluid Nissan Long Life Coolant (LLC) blue or green. Using universal mixtures or antifreezes of other colors (red, orange) can lead to sedimentation and clogging of the radiator.
The main feature of the original composition is the absence of silicates and phosphates, which protects aluminum engine parts from corrosion. If you decide to replace the brand, look for an analogue with the marking GLACIALBLUE or specification Nissan ES-52446M. Do not mix different types of fluids as their chemical additives may react.
The cooling system volume is approx. 9.5 liters (including the radiator and engine block), so for a complete replacement you will need 2 canisters of 5 liters each. Purchasing smaller containers is not advisable, since when topping up during operation, the volume will still not correspond to the norm.
Preparation for the procedure and necessary tools
Before starting work, make sure that the engine is completely cool. Open the expansion tank cap on a hot engine strictly prohibited due to the risk of severe burns from steam and boiling liquids. The ideal time to work is in the morning, when the car has been sitting overnight in the garage or on the street.
You will need the following tools and materials:
- 🔧 10 mm wrench or socket for unscrewing the radiator drain plug
- 🔧 Container for draining waste liquid (volume of at least 10 liters)
- 🔧 Funnel for convenient filling of new antifreeze
- 🔧 Clean rags and gloves to protect your hands
- 🔧 Distilled water (if you plan to flush the system)
It is also worth preparing a jack or stands to provide access to the bottom of the radiator. Some owners choose to remove the front bumper for convenience, but this isn't always necessary if you have a long enough wrench and good visibility.
⚠️ Warning: Old coolant contains toxic substances. Do not pour it down the drain or onto the ground. Use a sealed container and dispose of waste at specialized collection points.
- Blue (Original Nissan)
- Green (Analog)
- Red (Not recommended)
- Orange (Not recommended)
Step-by-step instructions for draining old fluid
We begin the procedure by opening the hood and unscrewing the expansion tank cap. This action is necessary to discharge the system so that the liquid drains faster. Make sure the cover is completely removed and does not interfere with access to other components.
Next, jack up the car or look underneath the radiator. Locate the plastic drain plug located at the bottom of the radiator. Carefully unscrew it with a key, substituting a previously prepared container. Be careful: the fluid flow can be powerful, especially if you open the reservoir cap.
After the main volume has flowed out, unscrew the lower radiator hose. This will help remove any remaining fluid from the engine block, since the radiator cap does not drain 100% of the way. Leave the system open for 15-20 minutes to drain completely.
☑️ Preparing for draining
If the drain plug shows signs of corrosion or does not tighten completely, do not use excessive force to avoid stripping the threads. It's best to use penetrating lubricant ahead of time. After draining, rinse the plug thoroughly and inspect the O-ring for damage.
Flushing the system and removing air pockets
If you notice that the drained liquid is rusty in color or contains mechanical impurities, it is necessary to flush the system. To do this, fill in distilled water, start the engine, let it idle until the fan turns on, then drain the water again. Repeat the procedure until the drained water becomes clear.
Engine Feature VQ35DE is a complex system of throttle valves and the presence of air channels. After adding new antifreeze air removal procedure is the most important step. Improper execution can lead to overheating and deformation of the cylinder head.
To remove air, follow these steps:
- 🚗 Raise the front of the car on a jack
- 🚗 Open the expansion tank cap
- 🚗 Start the engine and turn on the heater to maximum (temperature "Hot")
- 🚗 Monitor the liquid level in the tank, it will drop as air escapes
What to do if the level does not rise?
If the level in the expansion tank does not rise and the engine temperature rises quickly, an air lock may have formed in the cooling jacket. Try gently squeezing the upper and lower radiator hoses while the engine is running (careful, it's hot!) to force air into the reservoir.
Monitoring fluid levels is critical. If it falls below the minimum, the pump will begin to pump air, causing water hammer and damage to the impeller. Constantly add antifreeze while the engine is running until the level stops dropping and hot air comes out of the heater.
Before starting the bleeding procedure, warm up the engine to operating temperature, then turn it off, wait 5 minutes and open the reservoir cap again - this will help remove large air bubbles from the system.
Technical nuances and common mistakes of owners
Many owners Nissan Murano They make the mistake of closing the expansion tank cap immediately after filling. This prevents air from escaping and creates excess pressure. The lid must be kept open until the engine warms up to 90 degrees and the cooling fan turns on.
It is also worth paying attention to the condition of the thermostat. If, after replacing the antifreeze, the engine heats up too quickly or, conversely, does not reach operating temperature for a long time, the thermostat may be stuck. On VQ35DE The thermostat is located in a thermostat housing, which requires periodic inspection.
The table below shows the main characteristics of the coolant for your car:
| Parameter | Meaning | Note |
|---|---|---|
| Liquid type | Nissan Long Life Coolant | Blue/Green |
| Freezing point | -34°C | Can be diluted with distillate |
| System volume | 9.5 liters | Including radiator and reservoir |
| Replacement interval | 90,000 km / 3 years | When operating in difficult conditions - more often |
Do not forget to check the fluid level visually through the transparent walls of the expansion tank. If the level falls below MIN, you need to add antifreeze. Periodic level checking is the key to a long life of the cooling system.
Proper removal of air from the cooling system is the most critical stage of the replacement, on which the VQ35DE engine does not overheat.
Diagnostics after replacement and level monitoring
After completing all procedures, you must let the car run in warm-up mode for at least 30 minutes. During this time, keep an eye on the temperature gauge on the dashboard. It should stabilize at the middle of the scale. If the needle goes into the red zone, immediately turn off the engine and check for air in the system.
The next day after replacement, be sure to check the fluid level in a cold engine. The antifreeze may drop to normal levels and will need to be topped up. Do not mix different brands of antifreeze, even if they are the same color - the chemical composition may differ.
Inspect the hose connections and radiator for leaks. Even a small amount of liquid may indicate a poorly tightened plug or damaged pipe. Leaks on Murano Z51 often arise due to the age of plastic clamps, which lose elasticity over time.
Frequently asked questions about replacing antifreeze
Is it possible to mix blue and green antifreeze?
Mixing different colors of antifreeze is not recommended, as this can lead to a chemical reaction and sedimentation. It is best to use only original blue Nissan LLC fluid.
How often does antifreeze need to be changed on a Nissan Murano Z51?
The manufacturer recommends replacement every 90,000 km or every 3 years. When operating in conditions of frequent traffic jams and high temperatures, it is better to reduce the interval to 2 years.
What should I do if the engine overheats after replacement?
Most likely, an air lock has formed in the system. It is necessary to repeat the bleeding procedure, possibly with the front of the car raised. If the problem persists, check the operation of the thermostat and fan.
Can distilled water be used instead of antifreeze?
Only water should be used in emergency situations. Water does not have anti-corrosion properties and may boil at a lower temperature than antifreeze. This can lead to overheating and engine corrosion.
⚠️ Attention: If you notice that the antifreeze level is dropping quickly, check the system for leaks. Radiator gaskets or heater hoses often leak on Nissan Murano Z51.
Following all recommendations for replacing coolant will allow your Nissan Murano Z51 serve you faithfully for many years to come. Regular maintenance not only saves money on repairs, but also guarantees your safety on the road. Don't put off replacing until later, especially if winter is approaching or you are planning a long trip.