Bosch Automotive Aftermarket in Philippines

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Up-to-date information for a successul workshop

No. 06/2018

Auxiliary Drive

Alternator Overrunners from Bosch

Alternator Overrunners from Bosch


  • OAP (Overrunning Alternator Pulley)
  • OAD (Overrunning Alternator Decoupler)

Both OAPs and OADs have a simple overrunning clutch.

OADs also have a torsion spring to absorb energy. This enables rotational irregularities in the crankshaft to be evened out better.


While the engine is running, a faulty alternator overrunner can be identified by the rough running characteristics of the pulley and any associated noise. It can also result in the vehicle battery not being charged due to the pulley being able to spin in both directions. OAPs and OADs always rotate freely in one direction. OAPs will immediately lock in the opposite direction, and OADs rapidly build up resistance to turning in the opposite direction until they lock. If any of the failure symptoms mentioned above are present, the alternator overrunner must be replaced.

A correctly functioning overrunner can be identified by smooth operation and the alternator coming to a delayed standstill after the engine is switched off.

Resulting damage

If the alternator overrunner becomes jammed, the engine’s rotational vibrations cannot be evened out. At low engine speeds, these vibrations cause the belt to run roughly and the tensioning components are subjected to higher than normal loads. Not only does this increase belt wear but other components in the auxiliary drive (e.g. tensioning and deflection rollers, torsion vibration dampers) may also fail prematurely.

Subject to the application, the overrunner can either be replaced in the vehicle or with the alternator removed and placed on a firm support (e.g. workbench).

Alternator Fitting

  • Depending on the rotational direction of the alternator, the overrunner has either a left- or right-hand thread.
  • Insert a suitable fitting tool (1) into the overrunner’s serration (2), and use an appropriate insert/socket (3) to hold the rotor shaft in place.
  • Use a ring spanner (4) to loosen or tighten the overrunner. Tightening torque: 80 Nm.
  • If the alternator overrunner is designed for use with a cover cap, fit the new cover cap supplied.


When removing or fitting the alternator overrunner, never lock the alternator fan as this can result in damage to the fan.


If the alternator overrunner has failed, tensioning and deflection rollers may also be damaged. They must also be checked for correct function and replaced if necessary.

High-pressure injection valves
No. 04/2018

Great to work with: High-pressure injection valves

Treating high-pressure injection valves properly enables them to be repaired effectively

Repair of high-pressure injection system components

Bosch supplies spare parts and special tools for the repair of the high pressure injection systems. ESI[tronic] 2.0 gives a complete diagnostic sequence to be followed with installation instructions including measurement values, fault patterns and even signal images. With this sort of help from Bosch’s detailed instruction manual, spare parts and special tools, it is a relatively easy task to remove or replace high-pressure injection valves and combustion chamber seals.

Removal and installation of high-pressure injection valve (HPIV)

  • Read ESI[tronic] 2.0 instructions carefully
  • Use appropriate tools to remove HPIV and replace the combustion chamber seal
  • Avoid damage to the valve tip (valve leakage)
  • Prevent the ingress of foreign bodies and dirt during installation
  • If the HPIV is to be reused, never use impact tools during the installation of the HPIV into the cylinder head
  • Do not apply oil or grease to the white Teflon seal
  • Apply a thin coat of clean, silicone-free engine oil to the blue seal before installing the fuel rail
  • When removing and reusing the HPIV, always replace the specified spare parts (service kits)

Important Notices

  • The engine must be cold during the repair work
  • The Fuel high-pressure system must be depressurised when working on it
  • Never disconnect fuel lines while the engine is running

‘Step by step’ removal and installation instructions for HPIV and HPP can be found on the Internet

Bosch installation instructions - Gasoline high-pressure injector (Video)

Bosch installation instructions - High-pressure injection pump (Video)

High-pressure injection valves

Special tools

  • Set 0 986 616 097 with assembly drift and adjustment ring for installation of the combustion chamber seal
  • For the removal of a high-pressure injection valve:
    • Spindle extractor 0 986 616 100
    • Impact extractor 0 986 616 101 (only use when valves are seized)

Spare parts

  • O-ring for high-pressure injection valve (HPIV)
  • Combustion chamber seal (Teflon ring)
  • Support shim
  • Hold-down tool

Bosch air filters
No. 03/2018

Bosch air filters

Explore product characteristics and customer benefits

Terminus for particles of dirt of all kinds

The tasks of an air filter are to protect the motor from particles of dirt in the entrained air, to protect the motor from abrasive wear and to assure the supply of air for air/fuel mixture preparation.

Regularly change the air filter according to the vehicle manufacturer’s instructions!

Consequences of a clogged filter:

  • Reduced air intake, leading to decreased engine output and increased pollutant emission
  • Higher fuel consumption
  • Problems when starting the engine
  • Premature oil contamination

Quality is worth paying for. Find a comparison of Bosch air filters here:

Bosch air filtres
Sales arguments at a glance

Customer benefits:

  • Long service life, high particle collection rate, wet strength, and high tensile strength
  • High level of dirt absorption capacity and low flow rate resistance
  • Stable pleat geometry
  • Perfect fit

Product characteristics:

  • Multi-layer, specially impregnated filter medium
  • Large filter surface area
  • Specialist impregnation of the filter medium
  • Precisely adapted shape and high-quality gasket material

Bosch Aerotwin
No. 02/2018

Aerotwin passenger car flat-blade wipers

Bosch Aerotwin: leading technology in the field of flat-blade wipers

Bosch Aerotwin

Development and innovation

Maximum comfort, trailblazing design

All components are developed based on specific vehicles, and cutting-edge tools are used to fine-tune the wiper system.

Bosch uses the wind tunnel to perform tests under various wind conditions and speeds up to 160 km/h, for instance.

Large-scale manufacturing

Special, multi-award-winning Bosch rubber mixture

Consistently high rubber mixture production quality thanks to sophisticated lab analyses prior to production approval.

The wiper rubber is durable due to its high resistance to abrasion, UV light and aging as well as high cold and heat elasticity.

Performance and stress testing

Safety and reliability are the foremost principles

Strict performance and stress tests carried out in the testing laboratory as well as directly on the vehicle are the basis for the consistently high quality of Bosch windscreen wipers.

Subject to testing are, among others, resistance to environmental and ozone impacts, chemical stress and abrasion.

Performance tests assess wiping quality, noise generation, high-speed performance and service life to ensure long-lasting wiping quality.

Bosch Aerotwin
Wiper rubber with Power Protection Plus

The aerodynamic design and patent Power Protection Plus wiper rubber ensure optimum visibility in any weather conditions.

Find all benefits at a glance here >

Cabin filter range
No. 01/2018

Cabin filters

Quality testing of the FILTER+ cabin filter

FILTER+ cabin filter

Quality testing: Filtration efficiency

An important quality criterion for a cabin filter’s performance is its filtration efficiency or its capacity to filter out particles. Bosch had its FILTER+ and a similar OE filter tested by the independent institute Flatech GmbH, Germany. Measurements were made in accordance with ISO 11155-1.

Test results*

Particulate matter test:
Bosch’s FILTER+ offers highly efficient protection against respirable particulate matter (particle size < 2.5 μm), surpassing even a similar OE filter.

Pollen test (ragweed and birch):
Bosch’s FILTER+ provides the same high degree of efficient protection against allergens as a similar OE filter.

*find graphs and more information in full article below

Cabin filter range
Workshop Tip

Bosch recommends that you change the cabin filter once a year or every 15,000 km.

Consequences of a clogged filter:

  • Reduced vision from fogged windows, resulting in reduced safety
  • Increased pollutant concentration inside the vehicle
  • Allergic reactions, e.g. sneezing
  • Reduced cooling capacity of the air-conditioning system resulting from deposits on the evaporator