Crossover operation Nissan Murano the second generation (Z51 body) often confronts owners with the need to maintain attachments. The alternator, a key element of the charging system, may require replacement or repair over time. On cars with a VQ35DE engine, which was installed on this model, access to the unit is complicated by the layout of the engine compartment.
Many car owners try to solve the problem on their own, but do not know which way to approach the problem. An incorrect approach can result in damage to hoses, clamps or the housing itself generator. In this article we will analyze in detail the algorithm of actions, the necessary tools and technical nuances that are critical for successful dismantling without wasting time and nerves.
Preparation of the workplace and necessary tools
Before you begin to physically impact vehicle components, you must ensure safe working conditions. Crossover Nissan Murano Z51 has a fairly spacious hood, but the dense layout of the engine requires careful preparation. You will need a pit or a lift, since some operations are more convenient to perform from below, as well as a set of keys and sockets.
The main tool for this procedure will be a set of sockets, including extensions and universal joints. Pay special attention 14 mm head for unscrewing the fastening bolts and by 10 mm to remove battery terminals. Also, do not forget about the pry bar or crowbar, which will be needed to tension the belt and remove the pulleys.
- 🔧 Set of socket heads (from 8 to 17 mm) with extensions
- 🔧 Ratchet wrench with crank and cardan
- 🔧 A prybar or a long screwdriver for working with the tensioner
- 🔧 Torque wrench for correct tightening during assembly
- 🔧 Rags and container for draining antifreeze (if required)
It is important to ensure that the engine is completely cool. Working with a hot engine VQ35DE may cause burns, especially when removing the cooling system pipes. If you are planning to shoot upper radiator hose to improve access, this should be done only after the system has cooled down.
Removing protective elements and turning off the electrics
The first step is to de-energize the vehicle. Remove the negative terminal from the battery using a 10mm wrench. This is a mandatory safety requirement, since if the wrench is accidentally shorted to the body generator A serious electrical fault may occur.
Next, you need to dismantle the plastic protection elements. On Nissan Murano Z51 This is usually a plastic shield at the bottom of the engine compartment. It is attached to plastic clips, which are easily broken if handled carelessly, so use a special spatula or flat-head screwdriver, prying them out carefully.
After removing the protection, you will have a view of the belt drive. Please note the condition automatic belt tensioner. It is located in the central part of the engine and is a complex unit that requires careful handling. Do not attempt to disassemble it unless necessary.
⚠️ Attention: When disconnecting the battery for Nissan Murano The audio system code may be reset. Make sure you have the PIN code for the radio before removing the terminal, otherwise you will have to contact your dealer to unlock it.
Loosening the belt and removing the pulley
The key step is removing the drive belt. To do this, you need to release the tension using an automatic tensioner. Take a 14 mm socket (or 17 mm, depending on the tensioner modification), place it on the tension roller bolt and smoothly turn clockwise to release the belt.
By removing the belt, you can access the alternator pulley. Here lies the main difficulty: the pulley is secured with a bolt with a left-hand thread or has a specific design. In some cases, a special tool is required to keep the pulley from turning, but often a pry bar can be used against the gear teeth (safe on metal).
If you find that the pulley cannot be unscrewed, do not use excessive force. Use a penetrating lubricant WD-40 and give it time to soak into the carving. Excessive force may strip the splines or damage the generator rotor, rendering the unit unsuitable for repair.
The nuances of working with a tensioner
Automatic tensioners on VQ35DE engines lose spring force over time. If, when removing the belt, you notice that the pulley is loose or does not hold tension, it is strongly recommended that you replace the tensioner assembly rather than try to repair it. This will save you time in the future and prevent the belt from breaking during operation.
Disconnecting communications and fastenings
After removing the pulley and belt, proceed to disconnect the electrical connectors. Open the protective plastic cap on the back generator and disconnect the main power connector. Also, do not forget to unscrew the nut securing the thick power wire (plus), which goes directly to the battery through the fuse block.
Next, you need to remove the mounting brackets. On the engine VQ35DE The generator is secured with two main bolts: one at the top and one at the bottom. The top bolt is often difficult to access due to the intercooler pipes and crankcase ventilation system. Sometimes you have to remove the upper radiator hose or the intercooler itself to gain normal access.
If access from above is blocked, try to perform the basic operations of unscrewing the lower bolt from below the car. This is often easier and faster. Use an extension to reach the bolt located deep in the engine pan.
☑️ Preparation for dismantling the generator
Removing the unit from the engine compartment
When all the fasteners are unscrewed and the communications are disconnected, you can begin to extract generator. This requires caution as the knot is heavy and has a complex shape. Carefully tilt it, being careful not to catch hoses and wires of nearby units, such as power steering or air conditioning compressor.
In some configurations Nissan Murano Z51 removal of the generator is only possible through the top if it does not interfere with the dismantling of other large components. In other cases, it is more convenient to bring it out from below if there is enough space. Assess the situation visually before making any effort.
If you are planning a replacement engine mounts or generator bracket, then this moment is ideal for inspecting them. Check the condition of the rubber bushings, as their wear can lead to vibrations and subsequent failure of new parts.
- Brush wear
- Diode bridge fault
- Bearing failure
- Problems with the voltage regulator
- Other
Features of installing a new unit and diagnostics
Installation of new or refurbished generator is done in the reverse order of removal. The main rule is not to tighten the fastening bolts until the final assembly of all components. This will allow you to adjust the position of the unit if it is not seated tightly.
After installing all the fasteners and connecting the electrics, be sure to check the correct belt tension. Although the tensioner is automatic, make sure it is not in its limit position (fully extended or fully compressed). This may indicate that the belt length is incorrect or the tensioner itself is worn.
Before starting the engine, make sure that all tools are removed from the engine compartment. Start the engine and let it idle. Keep an eye on the charging lamp on the dashboard - it should go out immediately after starting.
| Parameter | Meaning | Note |
|---|---|---|
| Pulley bolt tightening torque | 100-110 Nm | Use a torque wrench |
| Generator mounting torque | 40-50 Nm | Top and bottom bolts |
| Belt diameter | 6PK2250 | Check the markings on the old belt |
| Battery voltage (at idle) | 13.8-14.4 V | Checking with a multimeter |
| Engine type | VQ35DE | 3.5 liters, V6 |
It is critical to check the voltage at the battery terminals immediately after installing a new alternator. If the voltage is lower than 13.5 V or higher than 14.8 V, then the new unit is defective or incorrectly connected.
Common errors and maintenance tips
One of the most common mistakes when replacing is the use of non-original bolts. On Nissan Murano bolts with a certain strength are used. Replacing them with cheaper analogues can lead to thread breakage due to vibration, which, at best, will require repeated disassembly, and at worst, will lead to the generator falling onto the road.
Also, do not neglect replacing belt when removing the generator. If the belt has cracks, traces of oil or wear, it must be replaced. An old belt can slip on a new generator, causing overheating and rapid wear of the bearings.
Please note the condition contacts in the power connector. Contact oxidation can result in poor connections and false charging fault messages on the dashboard. Clean the contacts with fine sandpaper or treat them with contact lubricant.
⚠️ Attention: When installing a new generator Nissan Murano Z51 Make sure you do not reverse the polarity of the wires. A positive-to-ground short circuit can instantly destroy not only the new alternator, but also the engine control unit (ECU), leading to very expensive repairs.
FAQ: Answers to frequently asked questions
Do I need to remove the radiator to replace the alternator?
In most cases, to replace the generator with Nissan Murano Z51 There is no need to remove the radiator. It is enough to dismantle the upper radiator pipe and, if necessary, the intercooler to gain access to the upper mounting bolt. Removing the radiator is a last resort and is only necessary in cases of serious damage or specific modifications.
How to determine if the generator is faulty?
The main signs are dim headlights at idle, a lit battery light on the instrument panel, a grinding or howling noise from the engine compartment (wear of bearings), as well as unstable operation of the electronics. Accurate diagnostics can be carried out with a multimeter by measuring the voltage at the battery terminals with the engine running.
Is it possible to drive a Nissan Murano without a generator?
Technically it is possible, but only for a short distance and with consumers turned off (headlights, air conditioning, audio system). The engine will run on the energy stored in the battery. As soon as the battery charge runs out, the engine will stall. It is strictly not recommended to drive modern cars without a generator., as this may lead to complete discharge of the battery and damage to the electronics.
How long does it take to replace a generator?
For an experienced technician, replacing the generator with Nissan Murano Z51 takes from 1.5 to 3 hours, depending on the availability of the engine compartment and the need to remove additional components (pipes, intercooler). A beginner may need more time, especially when unscrewing hard-to-reach bolts.