To reduce engine vibration during shutdown, a new throttle closing strategy has been introduced to reduce fuel injection in a smoother and more controlled manner. At the same time, the generator is switched off to reduce the load on the engine.
Changes to the ECM software and new engine calibration make shutdown even smoother. In addition, the optimized engine mounting and adjustment reduces vibration at start-up.
Components directly involved in starting and shutting down the engine have been upgraded or replaced due to an increase in the number of shutdowns and starts throughout the vehicle's life cycle. This section describes these upgraded and more durable components.
CAUTION: To ensure correct operation of the automatic system "Stop/Start", only recommended parts should be used when replacing components, since some components from previous vehicle models are suitable for TD4_e.
Starter
To increase reliability, taking into account the increased requirements for starting, the starter has undergone the following modifications:
- The seals have been upgraded.
- A wear-resistant contact material has been used to reduce wear on the starter solenoid.
- The drive gear is made of a stronger grade of steel.
Flywheel ring gear
Due to increased starting requirements, the flywheel ring gear is made from stronger steel with 25% more carbon, which increases the strength of the assembly.
Double flywheel
As in previous diesel models, a dual flywheel is installed, which allows for smoother operation when starting, stopping and running the engine at low speeds.
To provide even smoother operation for increased stop and start requirements, a new friction disc has been developed for the TD4_e dual flywheel. New friction disc, capable of withstanding seven times the pressure of a conventional disc, is made of PEEK (PEEK).
PEEK is a semi-crystalline thermoplastic resistant to organic and aqueous media. It has a high melting point, which makes it resistant to thermal degradation. In addition, it is one of the few plastics suitable for working in ultra-high vacuum. Commonly used in bearings, piston parts and pumps.
Battery with absorbent glass microfibre baffles
Conventional batteries lose their ability to hold a charge over time as the internal lead plates lose their properties during normal use due to constant vibration and erosion. The rate of aging depends on many factors, including charge and discharge cycles. Therefore, the powerful power consumption of the system "Stop/Start" adversely affects the life of this type of battery.
To counteract extended system discharge and charge cycles "Stop/Start" A high-performance battery based on glass microfiber absorbent baffle technology has been developed to reduce battery aging due to intensive use. The battery owes its success to absorbent baffles, which are thin sheets of glass microfiber between lead sheets. The glass absorbent baffle also absorbs battery acid, allowing more efficient use of the volume of the cans.
The glass absorbent baffle ensures proper operation of the electrolyte and also provides mechanical support for the lead plates, reducing vibration and therefore aging. This technology significantly increases the effective number of battery charge/discharge cycles. The battery also has exceptionally low internal resistance, allowing for a faster reaction between the acid and the plate material.
Absorbent glass baffle battery technology has the following advantages:
- The battery remains completely sealed thanks to the absorption of the fiberglass plates.
- Under freezing conditions, the expanding liquid cannot damage the plates as they are covered with fiberglass spacers; accordingly, there is almost no displacement of the plates.
- Vibration and shock do not harm the battery.
- Because the electrolyte is held in baffles, there is no need for battery maintenance.
The battery capacity is 80 Ah, i.e. it is theoretically capable of delivering 80 amps for one hour. During a typical engine start, a very high current is drawn for a fraction of a second, so the overall charge of the battery is hardly affected. Restarting the engine requires approximately 0.001% of a new battery's full charge.
If a new battery is installed in the vehicle, the BMS (battery monitoring) requires re-calibration, taking into account the increased battery capacity; this is done using Land Rover approved diagnostic equipment. If no diagnostic hardware is available, the BMS module will automatically recalibrate, however this may take up to 48 hours depending on how the vehicle is used. System "Stop/Start" will not function correctly until the BMS module is recalibrated.
In case of replacement of the BMS unit, it will be calibrated automatically; for more information, see "Battery monitoring system" Further.
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