Category Archives: Audi

Clutch replacement – Audi A3

The second generation Audi A3 wasmanufactured from 2003 until 2012 and was given a facelift in 2008. It is a hugely popular vehicle in the UK, with over 220,000 vehicles on the road, and is also a regular sight in aftermarket workshops. So with a few pointers from LuK, it should be easy for any garage to beat the book time of around five hours.

Nothing out of the ordinary is needed to complete the job, the only special tools required are a transmission jack, an engine support cradle and a long axle stand. A two-post ramp was used in this example, however a four-post ramp may not provide enough clearance. For safety reasons it’s considered best practice to disconnect the battery earth lead before commencing work. If the vehicle has alloy wheels it may be fitted with antitheft wheel bolts, so make sure you have the key before you start.

Open the bonnet and lift off the plastic engine surround. Unclip the battery cover and disconnect the battery terminals. Unplug the Mass Airflow Sensor (MAF) (pictured below) and release the clip and pipe connecting the air filter assembly to the inlet manifold.

Unclip and remove the small air plenum housing attached to the front panel and disconnect the small rubber pipe attached to the main housing. Remove the assembly by undoing the securing bolt and releasing the rubber grommet (pictured below) attaching it to the battery tray.

Undo the clamp securing the battery and lift it out of the tray. Remove the front part of the plastic battery surround by unclipping it and undo the bolts securing the base of the battery tray to the chassis. Release the electrical harnesses attached to the battery tray and slide out the tray (pictured below).

Disconnect the gear linkage cables by releasing the small clips at both ends (Figs 4 & 5) and stow the cables to one side.

Fig 4

Fig 5

Unbolt and remove the small gearbox support bracket and disconnect the slave cylinder. Remove the earth connection from the starter motor bolt (pictured below) and remove the bolt.

Unplug the reverse light switch (pictured below) and undo the upper bellhousing bolts.

Use the engine cradle to support the engine and remove the gearbox mounting bracket.

Raise the vehicle

Raise the vehicle and remove both front road wheels. Undo both front hub nuts and release the lower arms by undoing the bolts. Remove the intercooler pipe near the front bumper for better clearance and undo the gearbox rear steady bar. Undo the lower starter motor bolt and stow the whole unit to one side. Remove the nearside wheel arch liner and remove both driveshafts. Remove the inspection back plate on the gearbox and remove the exhaust manifold support bracket. While supporting the gearbox, remove the final lower bell housing bolts and lower the gearbox carefully to the floor.

With the clutch removed, check the Dual Mass Flywheel (DMF) for signs of heat stress and evidence of grease loss. The DMF should also be tested for freeplay and rock between the primary and secondary masses (LuK tool number 400 0080 10 is specifically designed for this purpose on all LuK manufactured DMFs). Full instructions and tolerance data for all LuK DMFs are contained on a CD which comes with this special tool.

Clean the first motion shaft splines and any debris from the bell housing (especially important when a release bearing has failed). It’s important to ensure that the release bearing is always replaced if the clutch and/or DMF are worn out. Put a small dab of high melting point grease (not a copper-based product) on the first motion shaft splines and make sure the new driven plate slides freely back and forth. This not only spreads the grease evenly but also makes sure you have the correct kit. Wipe any excess grease off the shaft and driven plate hub. Using a universal alignment tool and checking the driven plate is the correct way round (note “Getriebe Seite” is German for “Gearbox Side”) the clutch can be bolted to the flywheel evenly and sequentially.

Before fitting the gearbox, make sure the locating dowels are in place and not damaged. Refit any that have become dislodged and refit the gearbox. Make sure the gearbox bell housing bolts are secured before lowering the jack. Refitting is the reverse of the removal.

How to change a clutch on a Volkswagen Golf GT

The Double Clutch Gearbox is a semi-automatic transmission manufactured by VAG. This type of transmission has been utilised across the range of VAG models since being introduced in 2004 and it has proven to be a very popular choice for consumers and vehicles.

Unfortunately many garages in the UK IAM are not aware that this transmission can be easily diagnosed and repaired with a little extra knowledge and very little cost.

It may surprise many that the VAG Double Clutch Gearbox actually uses a Dual Mass Flywheel (DMF) which can be diagnosed in a similar manner to a manual gearbox. They are simple to replace and the parts are available from all local LuK supplying factors. To show how easy this is to do, in this month’s clutch clinic we will be looking at the replacement of the DMF on a Mk5 VW Golf GT TDi with the DQ250 wet transmission.

Check data sticker

Before commencing with the repair ensure that the vehicle you are working on does have a DQ250 type gearbox as this procedure does differ for other variations. The gearbox code can be identified on the data sticker in the handbook or in the boot. If you are unsure please call the LuK Technical Hotline who will be able to advise you accordingly.

Before starting the repair you will need to acquire a gearbox fluid re-filler tool which screws into the oil container and allows the oil to be pushed into the gearbox. You will also need a transmission jack, an engine support cradle and a long axle stand. A twopost ramp was used in this example however a four-post ramp may not provide enough clearance. For safety reasons its considered best practice to disconnect the battery earth lead before commencing work. If the vehicle has alloy wheels it may be fitted with antitheft wheel bolts, so make sure you have the key before you start.

Open the bonnet and lift off the engine cover. Remove the battery cover and disconnect the battery terminals. Undo the clamp holding the battery in place and lift the battery out of the tray. Disconnect the Mass Air-Flow sensor (MAF) and the air filter housing attached to the front slam panel. Undo the single allen key bolt (pictured below) securing the air filter housing and release the clips securing the assembly to the inlet manifold.

Disconnect any attached breathers and remove the entire air filter housing by pulling sharply upwards, allowing the rubber fixings to release.

tery surround and undo the fixing bolts in the base of the battery tray. Release any attached wiring harnesses and lift out the tray. Disconnect the gear linkage (pictured below) cable by marking the adjuster mechanism position and undoing the nut.

Remove the large circlip retaining the cable onto the securing bracket and release the cable and stow it to one side.

Remove the earth connection from the gearbox mounting bolt and clamp the coolant pipes connected to the cooler on top of the gearbox and disconnect them. Remove the electrical connections on the starter motor and both bolts securing it in place, allowing it to be removed. Disconnect the large round electrical connecter attached to the gearbox opposite the breather (pictured below).

Undo the bolts securing the coolant pipes for the oil cooler and stow them to one side. Use the engine cradle to support the weight of the engine and undo the upper bell-housing bolts. The gearbox mounting bracket can now be removed.

Raise the vehicle and remove the nearside front wheel and the wheel arch liner. Undo the nearside front driveshaft bolt and remove the lower arm nuts and release the lower arm. Undo the bolts securing the flanges to both sides of the gearbox and remove the nearside drive shaft. Unclip and remove the large intercooler pipe in front of the radiator and undo the single nut securing the electrical connectors (pictured below) attached to the side of the gearbox.

Drain the gearbox fluid and separate the two gearbox flanges by undoing the allen key (pictured below) bolt in the centre.

If the flanges are not removed the one attached to the long shaft fouls the DMF when trying to remove the gearbox and it makes it very difficult to remove. Undo the gearbox steady bar and the lower bell housing bolts and, while using the gearbox stand, lower the transmission to the floor.

Inspect the DMF

With the gearbox removed, visually check the DMF (pictured below) for signs of excessive grease loss.

The splines at the centre on the DMF locate onto the splines on the clutch attached to the gearbox and the condition of these splines should be checked for excessive wear. These types of DMF can’t be tested in the same manner as a conventional DMF so only a visual and audible inspection is required.

No reprogramming is needed to replace the DMF, simply unbolt the old unit and install the new one. Check the spigot bearing in the crankshaft for wear and replace if required. The seals on the clutch centre shaft and around the outer lip (pictured below) need to be checked for leaks and no fluid should be evident inside the bell-housing.

Before refitting the gearbox, make sure the locating dowels are in place and not damaged. Refit any that have become dislodged and refit the gearbox. Make sure the gearbox bell housing bolts are secured before lowering the jack. Refitting is the reverse of the removal.

Helping to prevent drive train noises

In the UK Schaeffler is renowned for its leading LuK clutch, INA tensioner and FAG wheel bearing brands, and the company always goes the extra mile to provide even better products for its customers. This was demonstrated by the efforts it made when building a new acoustic testing facility at its Technical Development Centre in Herzogenaurach, Germany.

A room within a room
A special feature of the facility is a ‘room-in-room concept’, where an entire room is spring-mounted inside a larger room so that it moves independently and can be completely isolated as it is decoupled from the oscillation of the rest of the building. Special bricks were imported from Sweden as the interior rooms had to be of particularly high density (at least 2,400 kg/m³). Unsurprisingly, it has been named ‘the wobble room’ by staff!

The company’s engineers in the Competence Acoustics Centre (part of the Technical Development team) investigate the origins of irritating noise using the latest state-of-the-art analytical methods to discover how noise is generated and what can be done to eliminate it at the beginning of development. As such, typical tasks include investigations of airborne sound and vibration behaviour in the vehicle drive train, as well as in the chassis and its components, such as ball screw drives and roll stabilisers.

In addition, engineers also examine plain bearings and rolling bearings of all types and designs that are used in applications such as production machinery, wind turbines, hydroelectric power plants, railway, medical technology and household applications.

Vehicle test stand: here vehicles up to the size of a delivery van can be examined from a noise technical point of view.

Hi-tech equipment
Equipped with state-of-the-art measurement and computer technology, three test rooms and the so-called ‘wobble room’ have been installed in a 180 square metre area.

CTO Prof. Dr. Peter Gutzmer said: “This is an audible and tangible further extension of expertise at Schaeffler. With the new Herzogenaurach acoustic centre, we have created ideal conditions to further optimise the globally networked development activities at Schaeffler and adapt to customer needs even better than before.”

Especially in the field of drive technology, customers are paying more and more attention to low friction coupled with the quiet operation of the individual system components, and this is also true for bearings in electric motors and devices for the home and office environments.

Acoustic issues from all areas of automotive and industrial engineering can also be addressed quickly and competently.

Dr. Arbogast Grunau, Senior Vice President Corporate R&D Competence and Service, said: “The expertise concentrated here is the result of long-standing experience in product and system development and it is continuously being developed further.

“We use our network of competence to spread our knowledge and experience throughout the world, with training and seminars being an important medium. In this way we make an important contribution to Schaeffler’s global alignment, true to our motto ‘Together we move the world’ – here with a particular focus on noise optimisation.”

Examination of airborne sound and vibration behaviour of car wheel bearings in an anechoic room

Reducing outside noise
The test rooms include a large acoustic vehicle test bay, a room for fatigue tests and one with extensive adaptation options. The ‘room-in-room concept’ covers 30-50 square metres of floor space with the largest room weighing more than 130 tons.

The interior ceilings and walls of the test rooms are lined with up to 35cm thick acoustic broadband compact absorbers to meet the sensitive metrological requirements of the acoustic staff.

Dr. Alfred Pecher, Manager, Testing Competence Centre Acoustics, said: “This constructional measure means it has also been possible to reduce noise intruding into the test rooms from outside – such as the sounds of trucks passing by – to a minimum, and to obtain technically accurate measurements.”

 Even large-size bearings weighing several tons can get inside the acoustic centre by means of a crane system, designed specifically for this purpose. They can also be examined there.

How to change a clutch on a Audi TT

In this month’s ‘Clutch Clinic’, the experts at LuK offer some handy hints to help out any independent garages that may be faced with a clutch and flywheel replacement on the Audi TT 2.0Tdi Quattro.

The Audi TT was launched in 1998 and has proven to be a popular two door sports car in the UK. With three generations of TT, the latest being launched in 2014, available in various engine options, the likelihood of one of these arriving through your workshop doors is high.

The vehicle may be fitted with alloy wheels so before starting the repair make sure that the locking wheel nut key is available. For safety, disconnect the battery which is found in the boot. For this repair we used a two post ramp, a transmission jack and an engine support beam.

Install the engine support beam

Remove both front wheels to begin with, then disconnect the sensor switch from the air filter housing and vacuum pipe and remove the air filter housing as a complete unit. Finally remove the air filter housing bracket. Install the engine support beam, applying slight tension to hold the engine and gearbox.

Remove the three top gearbox mount bolts and mounting bracket, as this restricts the gear link cables from being removed.

How to change a clutch on a Audi TT

Disconnect the gear linkage cables, one is secured with a plastic clip and the other is a key way fitment held with a nut. Remove the three bolts holding the gear link bracket and slide the one linkage cable from a sleeve and stow the cables safely using a bungee tie.

Disconnect the reverse light switch. Disconnect the clutch slave cylinder hydraulic pipe and blank and stow safely.

How to change a clutch on a Audi TT

Remove the starter motor bolts, one of which holds in place the earth lead which will need to be stowed, and then remove the starter motor carefully. Remove the top two bell housing bolts and then raise the vehicle. Disconnect the oil level sensor switch and drain the transmission oil.

Remove the engine under tray liner and the front wheel arch liners from both sides. Remove the under tray framework, looking out for the difficult bolts blocked by the air conditioning hose. They are, however, accessible without the need to remove any pipework.

How to change a clutch on a Audi TT
Disconnect the drive shaft nut and bolt configuration from the axle drive.
Disconnect the ball joints on both sides and remove the splined bolts (six on each side), holding the drive shafts to the drive flanges and carefully remove the drive shafts from position. Remove the rear gearbox support.

How to change a clutch on a Audi TT

Disconnect the prop shaft from the transfer box and support the front end of the prop shaft.
In this repair we decided to leave the transfer box attached, the clearance is a little tight and it will take some patience to free the gearbox, but it will come free.

How to change a clutch on a Audi TT

You can also disconnect the transfer box if you wish and to do this you will need to remove the five bolts holding the transfer box to the gearbox. One bolt is a 6mm Allen key bolt that is only accessible through the offside drive flange and you will need a very long extension to reach it.

How to change a clutch on a Audi TT

Remove the clutch

Support the gearbox with the transmission jack and remove the remaining bell housing bolts. Carefully free the gearbox from the engine and lower to the floor, taking care as it is a heavy transmission. Remove the worn clutch, concentric slave cylinder and check the dual mass flywheel.

Test for free play

In this example the dual mass flywheel (DMF) was also replaced with the clutch and slave cylinder. However in most cases you have no need to replace the DMF as this can be checked whilst on the vehicle for signs of heat stress and evidence of grease loss. The DMF should also be tested for free play and rock between the primary and secondary masses. LuK tool number 400008010 is specifically designed for this purpose. Full instructions and DMF tolerances can be found by searching “DMF data sheet” on www.schaeffler-aftermarket.com.

Clean the first motion shaft splines and any debris from the bell housing (especially important when a release bearing has failed). Put a small dab of high melting point grease (not a copper based product) on the first motion shaft splines and make sure the new driven plate slides freely back and forth. This not only spreads the grease evenly but also makes sure you have the correct kit.

Wipe any excess grease off the shaft and driven plate hub.

Fitting of the new clutch will require a special tool. The clutch is a self-adjusting clutch. After checking the spigot bearing, check the adjusting springs on the new clutch cover to make sure they are fully compressed. Fit the clutch alignment tool and locate it into the spigot bearing on the flywheel. Place the driven plate over the alignment tool, making sure the correct side is facing the gearbox (‘Getriebeseite’ means ‘gearbox side’ in German).

Bolt on the pressure plate, tightening each opposing bolt progressively around the cover until the desired torque setting is reached. Remove the special tool and fit the remaining bolts.
Refitting is the reverse of removal.

How to change a clutch on a Audi A6

RECOMMENDED LABOUR TIME: 5 HOURS LUK PART NUMBER: 624330800 OE REFERENCE: 038198141GX

The vehicle may be fitted with alloy wheels so, before starting the repair, make sure that the locking wheel nut key is available. For safety it is best to disconnect the battery which is found in the boot. In this repair we used a two-post ramp, a long axle stand and a transmission stand and cradle.

Open the bonnet and disconnect the battery. The remainder of the work is from underneath the vehicle. Raise the vehicle and remove both under-tray sections. Using the long axle stand, support the front of the engine and then remove the front engine mount.

Heat shield removal
Remove both of the drive shafts from the transmission side and stow the shafts out of the way using a couple of bungee ties. The offside drive shaft also has a heat shield that should be removed.

At this stage it is possible to loosen the bottom four bell housing bolts, keeping in mind one of them is a nut and bolt arrangement.

Remove the gearbox stabiliser bar and body stabiliser bar. Remove the bolts that hold the exhaust to the main gearbox support bracket and disconnect the exhaust system from the clamping sleeve before carefully splitting the exhaust and support using a bungee tie. Support the gearbox with the transmission jack and remove the main gearbox support bracket.

Disconnect the reverse light connecter.

Remove the gear link stabiliser bolt.

Remove the upper gear link stabiliser bolt, which is a captive bolt and washer from the top of the gearbox. Remove the bolt that holds the pushrod in place and remove the pushrod. Remove the selector shaft nut and disconnect the lever from the selector shaft.

Clamp the hydraulic line at the rubber pipe section and disconnect the external slave cylinder, keeping the line connected and stow safely.

The remaining bell housing bolts can now be loosened and all of them can be removed. Keep in mind that the bell housing bolts are all different sizes. Carefully detach the gearbox from the engine and lower the gearbox to the floor.

With the clutch removed, check the Dual Mass Flywheel (DMF) for signs of heat stress and evidence of grease loss. The DMF should also be tested for freeplay and rock between the primary and secondary masses; LuK tool number 400 0080 10 is specifically designed for this purpose on all LuK manufactured DMF’s. Full instructions and tolerance data for all LuK DMFs are contained on a CD which comes with this special tool.

The correct kit
Clean the first motion shaft splines and any debris from the bell housing (especially important when a release bearing has failed). It’s important to ensure that the release bearing is always replaced if the clutch and/or DMF are worn out. Put a small dab of high melting point grease (not a copper-based product) on the first motion shaft splines and make sure the new driven plate slides freely back and forth. This not only spreads the grease evenly but also makes sure you have the correct kit.

Wipe any excess grease off of the shaft and driven plate hub. Using a universal alignment tool and checking the driven plate is the correct way round (note “Getriebe Seite” is German for “Gearbox Side”) the clutch can be bolted to the flywheel evenly and sequentially.

Before fitting the gearbox make sure the locating dowels are in place and not damaged. Refit any that have become dislodged and refit the gearbox. Make sure the gearbox bell housing bolts are secured before lowering the jack.

Refitting is the reverse of the removal.

For the latest in online support log on to www.repxpert.com.

MEET THEM AT MECHANEX
Schaeffler Automotive Aftermarket’s three quality brands – LuK, INA and FAG – will all be in attendance throughout 2015 at our MECHANEX trade shows.

Offering visitors the opportunity to talk to Schaeffler’s group of experienced experts who will be on hand to offer helpful demonstrations and workshop hints, attendees can also find out about the latest technologies that will soon be appearing in their workshop.

Accessory Belt Drive System maintenance – Various models

Vehicle make(s): Various, including Audi, SEAT, Skoda and VW models
Engine: 1.9 TDi 8V

Developments at OE level mean that different models in the same vehicle range may be equipped with different Synchronous Belt Drive Systems that require specific sets of tools to complete the job. While this requires additional garage investment that must be recovered, it is the introduction of new drive system components in the ABDS that is likely to add significantly to the overall cost of drive system repairs.

When it comes to ABDS maintenance, things are tight and not just in relation to the tension on the belt. Garage customers have rarely been more aware about the price of parts and the cost of vehicle repairs, but it’s hard to convince them to spend now and save later.

Gates, one of the world’s largest manufacturers of OE belts and tensioners, argues that if a symptom is cured but the cause of the problem remains undetected, the vehicle will be back for a rectification job. And next time, the problem may be more serious.

Vibration control
In order to deal with a lot of vibrations in the ABDS, modern engines are equipped with technology such as Overrunning Alternator Pulleys (OAPs) and Torsional Vibration Dampers (TVDs). Until recently, these components were rarely encountered in the aftermarket, let alone considered parts for inspection at belt replacement time. Now found in models in increasing numbers, they are expensive to replace, but even more expensive if not replaced as part of a preventive maintenance schedule.

Function and role
TVDs have important roles to play inside modern cars. In order to extend the operational lifetime of components powered by the belt, they absorb vibrations from the crankshaft. If the TVD fails, or its ability to dampen vibrations reduces through wear, there is a significant risk of damage to the belt and possibly the driven accessories. If left unchecked, a broken crankshaft becomes a very real possibility.

OAPs are more recent additions to ABDS technology. These have been designed to overcome variations in different component speeds within the drive. OAPs are special kinds of pulleys, which allow alternators to continue to run on when the engine speed decreases. This reduces the potential for belt slippage on the alternator pulley. Reduced Noise/Vibration/Harshness (NVH) and increased component life are important benefits.

Consequence of failure
By absorbing vibration and allowing the engine to perform to its true potential, OAPs and TVDs are inevitably subject to wear and begin to fail.

For example, an OAP that is underperforming generates vibrations that adversely affect the smooth running of the belt. The cumulative affect is to increase stress on the tensioner bracket, which begins to experience material fatigue. The ultimate consequence is the rupture of the tensioner bracket.

Analyses of examinations by Gates Inspectors on the aforementioned models show that rupture related to OAP wear will always take place at the same point: shearing takes place just above the connection of the tensioner bracket with the hydraulic damper. In such cases, shearing of the tensioner bracket is a symptom of the additional vibrations generated by the worn OAP and not the cause of the premature belt failure.

Mistaken identity
Unfamiliar with the components, mechanics often confuse the symptoms that are generated by wear of these components as problems with the belt. This is especially true in the wake of scheduled maintenance, where the OAP has not been considered for replacement at the same time as the belt.

Customers should be advised of the potential risks to the drive system if not replaced.

Conclusion and recommendations
OAPs as well as TVDs are not designed to operate for the lifecycle of the car. They are service items. So, it makes sense to replace them at the same time as the ABDS belt.

Product test – Diagnostic Associates DA-ST512 Service Tool

With JLR models a regular fixture in his workshop, Darren Cotton of AVC UK in Surrey was only too happy to put a new, specialist diagnostic servicing tool through its paces.

When it comes to identifying the right diagnostic tool for your business, there are many choices available to workshops. Some may be ‘all-makes’ or ‘universal’ in their coverage, while others are specifically designed for the more specialist user.

Either way, with most tools making pretty bold claims in terms of their capability, it always helps to be able to try them out first. I was happy, therefore, to take the DA-ST512 Service Tool from Diagnostic Associates for a test drive this month, and to let PMM’s readers know my thoughts.

This unit certainly falls into the ‘specialist’ diagnostic category and has been derived from the popular range of service ‘dongles’ that Diagnostic Associates launched to market in recent times. Specifically designed (and approved) for Jaguar/Land Rover vehicles, it is a dedicated servicing tool that also doubles up as a ‘Pass-Thru’ unit to work with SDD (Symptom Driven Diagnostics). 

Tool basics
The DA-ST512 comes as a handheld unit that connects directly to the OBD2 diagnostic connector and, using its simple menu structure displayed on the back-lit LCD screen, it will perform a vast amount of applications on JLR models (2005 onwards).

The device is very easy to use, extremely quick and has a high quality feel to it. It also benefits from a long lead that is attached to the diagnostic socket to make manoeuvring light work.
The unit will power up instantly when connected to the OBD2 socket and, with the ignition on, it identifies the vehicle within seconds, displaying the vehicle details and VIN. Using its dynamic menu system, it is able to identify which of the installed applications are suitable for the vehicle it is connected to, meaning you can go straight into the function you desire.

Available functions
The basic operation package consists of six applications:
1. Service Interval Reset (SIR)
2. DPF Dynamic Regeneration (DPFDR)
3. DPF Adaption Reset (DPFAR)
4. Electronic Park Brake Release (EPBR)
5. Tight Tolerance Mode Toggle (TTMT)
6. VCI Gateway Module (J2534)

It also features another 17 applications that are available for a small fee, however all can be used on a ‘trial’ basis for a maximum of three times before the function is made unavailable (until you pay for it that is!). This is a great feature because if you were looking to add an application you can ‘try before you buy’ – something I’ve not seen on many tools before.

Putting it to the test
So what sort of use did I get out of the applications? The short (and honest) answer is ‘plenty’. Here’s a quick overview of the types of task I was able to undertake during the test period:

Electronic Park Brake Release (EBPR)
This function will force the brake to move back to its mount mode and release the brake pads from the disc, enabling you to replace the brake pads safely. In the case of Land Rover vehicles it can also perform the ‘un-jam’ function before moving to the mount position. The device again made a rapid connection and readers will no doubt agree that functions like this save a lot of time in the workshop.

Diesel Particulate Filter Dynamic Regeneration (DPFDR)
Having this on the tool is very handy, as it negates the need to tie up SDD or any other device you would use for this operation. Like all the applications on this device, it only takes around 30 seconds to start the procedure. Once the vehicle has reached target temperature, and if the soot content is higher than 60 grams, the unit will emit an audible sound for three seconds at 10 second intervals. This now means the vehicle must be driven above 40kph for 15 minutes before a short, high-pitched sound confirms the process is performing correctly.

Service Interval Reset (SIR)
This was the most popular application that I made use of. Other tools on the market seem to struggle with resetting JLR service lights after servicing but the DA-ST512 had no such problems. Within 30 seconds of connecting the device, the application will remove the service warning from the instrument cluster and reset the counters (including oil counter reset, where applicable) and this worked every time…

Read/Clear Diagnostic Trouble Codes (DTCs)
This function allows you to read and clear the DTCs for all the ECUs on the vehicle or you can select an individual network such as: H Can, Low Can and MOST. It’s very quick and displays the codes correctly, along with manufacture code and description. Adding the live data viewer to the device will also give you some quick assistance and information to aid your diagnosis.

Tight Tolerance Mode Toggle (TTMT)
If you carry out wheel alignment in your workshop then this application is vital. The vehicle’s suspension (on some associated models) will need to be locked at a known level to allow geometry checks and adjustments – this is where you will need to use TTMT.

Headlamp levelling
Which is a typical task for body repair shops – can’t be done correctly if the conditions are not met, so the tool again proved very proficient in this area. The process can take up to two minutes to enter or, if you walk away and leave it in TTMT, a “PROCEDURE COMPLETE” message will be displayed.

J2534 Symptom Driven Diagnostics
This function is one of the tool’s hidden gems: one minute it’s a quick service unit, carrying out all of the aforementioned functions, and the next it will double up as a Pass-Thru device which can work in conjunction with SDD to give you main dealer capabilities.

For the function to work you just download the driver from the Diagnostic Associates website. This is very simple to do and works very well, however the instructions for installing and connecting must be followed precisely. Again, this is all featured on DA’s website.

Device registration and updating
This process couldn’t be any simpler and only takes a few minutes. Once registered, you can download the DA App Hub (a PC-based application) from the Diagnostic Associates website and this will allow you to update the current applications you have on the device (for FREE). It’s very easy to navigate and will instantly display the updates that are available on the home screen. Furthermore, you can purchase a raft of additional applications (such as suspension height calibration) as you see fit. All of these cost between £15 and £55 and represent excellent value-for-money.

VERDICT: A cracking, cost-effective unit that I’d recommend to any workshops that want to improve their JLR servicing capabilities!

What to do if you encounter thermostat failure

A scenario that will sound familiar to most garage technicians is when a customer reports that, when in traffic, the temperature gauge rises into the red danger zone. A failed thermostat is confirmed as the cause. It’s a problem that could lead to severe engine damage and, usually, it’s a straightforward repair job that won’t break the bank.

For drivers of certain VW group applications (fitted with V6 engines) and some Vauxhall/Opel Group models (fitted with 4 cylinder engines) the cost of the repair can be a lot more expensive. That’s because in these engines, the thermostat sits directly behind the Synchronous Belt Drive System (SBDS) or timing belt assembly. It means that in order to fit a replacement thermostat, the drive belt must be removed.

Examples of VW group applications with such a configuration include the Audi A4 2.4 (Petrol), Audi A4 Cabrio 2.4 (Petrol) & 2.5 (Diesel), Audi A6 2.4 (Petrol) and Audi A8 2.8 (Petrol). Vauxhall/Opel models with similar layouts are the Astra 1.6 and 1.4 (Petrol) and the Corsa 1.2 and 1.4 (Petrol).

Overhaul procedure
Gates advises that if the thermostat on any one of these vehicles fails ahead of a scheduled SBDS overhaul, you should consider bringing the overhaul procedure forward. It is not just good engineering practice, it makes sound economic sense.

Most experienced drive system installers accept that a used timing belt must not be refitted. This is because the correct ‘installation tension’ only ever occurs once – at the point of installation on a cold engine. These parameters are set when the engine is on the OE assembly line.

Installation tension is a critical aspect with respect to overall engine performance and it can only be achieved with a new belt. Most installers also accept that it makes little sense to install new belts without fitting new tensioners and it’s also a good opportunity to replace the water pump (where fitted) in order to ensure that a subsequent leak will not compromise the integrity of the new drive.

For this reason Gates introduced its Kit Plus Water Pump range in 2005. It was a move that gave installers – and their customers – peace of mind. Installers can be sure that the correct water pump is always being supplied. Customers are reassured that in the event of a problem, only one warranty inspection is required because the water pump, belt and tensioner is from a single source.

Kit’s the business
The supplier’s latest initiative is a kit designed to resolve the situation that technicians might face when vehicles with a thermostat located behind the SBDS arrive on the garage forecourt.

Available from this month, the range of ten PowerGrip® Kit Plus Water Pump Plus Thermostat kits also include all of the appropriate seals and gaskets. The initiative fits perfectly with the Gates principle that overhaul, as part of a preventive maintenance approach, is a better investment than a series of piecemeal repairs.

As the cost of replacing the thermostat on these models is relatively small in comparison with replacing the timing belt and its associated tensioners, the new kits provide a cost-effective solution.

Helping to prevent drive train noises

In the UK Schaeffler is renowned for its leading LuK clutch, INA tensioner and FAG wheel bearing brands, and the company always goes the extra mile to provide even better products for its customers. This was demonstrated by the efforts it made when building a new acoustic testing facility at its Technical Development Centre in Herzogenaurach, Germany.

A room within a room
A special feature of the facility is a ‘room-in-room concept’, where an entire room is spring-mounted inside a larger room so that it moves independently and can be completely isolated as it is decoupled from the oscillation of the rest of the building. Special bricks were imported from Sweden as the interior rooms had to be of particularly high density (at least 2,400 kg/m³). Unsurprisingly, it has been named ‘the wobble room’ by staff!

The company’s engineers in the Competence Acoustics Centre (part of the Technical Development team) investigate the origins of irritating noise using the latest state-of-the-art analytical methods to discover how noise is generated and what can be done to eliminate it at the beginning of development. As such, typical tasks include investigations of airborne sound and vibration behaviour in the vehicle drive train, as well as in the chassis and its components, such as ball screw drives and roll stabilisers.

In addition, engineers also examine plain bearings and rolling bearings of all types and designs that are used in applications such as production machinery, wind turbines, hydroelectric power plants, railway, medical technology and household applications.

Vehicle test stand: here vehicles up to the size of a delivery van can be examined from a noise technical point of view.

Hi-tech equipment
Equipped with state-of-the-art measurement and computer technology, three test rooms and the so-called ‘wobble room’ have been installed in a 180 square metre area.

CTO Prof. Dr. Peter Gutzmer said: “This is an audible and tangible further extension of expertise at Schaeffler. With the new Herzogenaurach acoustic centre, we have created ideal conditions to further optimise the globally networked development activities at Schaeffler and adapt to customer needs even better than before.”

Especially in the field of drive technology, customers are paying more and more attention to low friction coupled with the quiet operation of the individual system components, and this is also true for bearings in electric motors and devices for the home and office environments.

Acoustic issues from all areas of automotive and industrial engineering can also be addressed quickly and competently.

Dr. Arbogast Grunau, Senior Vice President Corporate R&D Competence and Service, said: “The expertise concentrated here is the result of long-standing experience in product and system development and it is continuously being developed further.

“We use our network of competence to spread our knowledge and experience throughout the world, with training and seminars being an important medium. In this way we make an important contribution to Schaeffler’s global alignment, true to our motto ‘Together we move the world’ – here with a particular focus on noise optimisation.”

Examination of airborne sound and vibration behaviour of car wheel bearings in an anechoic room

Reducing outside noise
The test rooms include a large acoustic vehicle test bay, a room for fatigue tests and one with extensive adaptation options. The ‘room-in-room concept’ covers 30-50 square metres of floor space with the largest room weighing more than 130 tons.

The interior ceilings and walls of the test rooms are lined with up to 35cm thick acoustic broadband compact absorbers to meet the sensitive metrological requirements of the acoustic staff.

Dr. Alfred Pecher, Manager, Testing Competence Centre Acoustics, said: “This constructional measure means it has also been possible to reduce noise intruding into the test rooms from outside – such as the sounds of trucks passing by – to a minimum, and to obtain technically accurate measurements.”

 Even large-size bearings weighing several tons can get inside the acoustic centre by means of a crane system, designed specifically for this purpose. They can also be examined there.

How to change a clutch on a Audi A6

Heat shield removal
Remove both of the drive shafts from the transmission side and stow the shafts out of the way using a couple of bungee ties. The offside drive shaft also has a heat shield that should be removed.

At this stage it is possible to loosen the bottom four bell housing bolts, keeping in mind one of them is a nut and bolt arrangement.

Remove the gearbox stabiliser bar and body stabiliser bar. Remove the bolts that hold the exhaust to the main gearbox support bracket and disconnect the exhaust system from the clamping sleeve before carefully splitting the exhaust and support using a bungee tie. Support the gearbox with the transmission jack and remove the main gearbox support bracket.

Disconnect the reverse light connecter.

Remove the gear link stabiliser bolt.

Remove the upper gear link stabiliser bolt, which is a captive bolt and washer from the top of the gearbox. Remove the bolt that holds the pushrod in place and remove the pushrod. Remove the selector shaft nut and disconnect the lever from the selector shaft.

Clamp the hydraulic line at the rubber pipe section and disconnect the external slave cylinder, keeping the line connected and stow safely.

The remaining bell housing bolts can now be loosened and all of them can be removed. Keep in mind that the bell housing bolts are all different sizes. Carefully detach the gearbox from the engine and lower the gearbox to the floor.

With the clutch removed, check the Dual Mass Flywheel (DMF) for signs of heat stress and evidence of grease loss. The DMF should also be tested for freeplay and rock between the primary and secondary masses; LuK tool number 400 0080 10 is specifically designed for this purpose on all LuK manufactured DMF’s. Full instructions and tolerance data for all LuK DMFs are contained on a CD which comes with this special tool.

The correct kit
Clean the first motion shaft splines and any debris from the bell housing (especially important when a release bearing has failed). It’s important to ensure that the release bearing is always replaced if the clutch and/or DMF are worn out. Put a small dab of high melting point grease (not a copper-based product) on the first motion shaft splines and make sure the new driven plate slides freely back and forth. This not only spreads the grease evenly but also makes sure you have the correct kit.

Wipe any excess grease off of the shaft and driven plate hub. Using a universal alignment tool and checking the driven plate is the correct way round (note “Getriebe Seite” is German for “Gearbox Side”) the clutch can be bolted to the flywheel evenly and sequentially.

Before fitting the gearbox make sure the locating dowels are in place and not damaged. Refit any that have become dislodged and refit the gearbox. Make sure the gearbox bell housing bolts are secured before lowering the jack.

Refitting is the reverse of the removal.

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MEET THEM AT MECHANEX
Schaeffler Automotive Aftermarket’s three quality brands – LuK, INA and FAG – will all be in attendance throughout 2015 at our MECHANEX trade shows.

Offering visitors the opportunity to talk to Schaeffler’s group of experienced experts who will be on hand to offer helpful demonstrations and workshop hints, attendees can also find out about the latest technologies that will soon be appearing in their workshop.