This procedure can apply to both the VW Touran and the Mk2 Ford Galaxy fitted with the 1.9 PD TDI engine. The basic procedure is the same, but the access a little more tricky on the Galaxy due to the different chassis design.

On the PD TDI engines, the alternator pulley is fitted with a one way freewheel roller clutch, the purpose of which is to allow the alternator to 'decouple' from the acceleration/ deceleration forces produced by the crankshaft of the engine. Many vehicles are fitted with these type of pulleys, particularly diesels due to their higher compression, for those interested in the reasons why take a read here. After extended periods the one way clutch can fail, when this happens it increases the strain on the auxiliary drive belt and associated components (tensioner, idlers etc) and can lead to belt squealing (especially at low engine speeds- during low speed manoeuvres, gearchanges etc) or oscillations. It also places a greater load on the engine.

My method of testing to check if the clutch is working properly is to remove the auxiliary drive belt from the alternator pulley and spin the pulley in the normal direction of rotation (clockwise when viewed from the pulley end of the alternator) as rapidly as you can by hand, then stop it spinning as quickly as possible. If the clutch is working properly the alternator rotor (the alternator internals you can see spinning when you rotate the pulley- arrowed yellow in the last image in this topic) should continue to spin for a brief period- we're talking half a second or so here- after you've stopped the pulley from turning. If you can't observe this happen then the clutch isn't working properly.

The pulley is available as a genuine part from the likes of Ford (Ford finis no. 1469755) or VW but you can likely save yourself a whack of cash by buying it from a factor or somewhere like here (I opted for the INA part as they produce most of the OE fitment pulleys). Be sure you get the right one as there are several different types available, possibly with different diameters. The old pulley carried the INA reference of F-227628.6, the replacement part was INA's stock code 535 0012 10 (and the pulley itself had the number F-553470.07 on it). Most sellers list which part numbers (the INA F-xxxxxx references) the pulleys they are offering will replace, so make sure before you buy! To remove and refit the pulley you will also need a special 33 splined removal tool, there are plenty of these on the likes of  [eBay] such as this, you also need a splined bit to hold the alternator shaft still whilst you remove the pulley- more on this below. The replacement pulley also comes with the protective plastic front cap which just serves as an additional barrier to prevent water, dust and dirt ingress into the pulley internals. The replacement part box contents and the spline pulley/ alternator shaft holding tools are shown in the below picture:

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On the Galaxy, it is my belief* that the alternator needs to be removed from the vehicle to carry out this task. Alternator removal on the Galaxy is covered in Mirez's article here (the only thing I would add is that the tensioner on my Mk2 Gal has a lug that accepts a 16mm open ended spanner, not a 17mm as in the article). The reason for this is that there is insufficient space between the alternator pulley and the plastic engine bay front panel (with the alternator installed) to get the pulley removal tool AND the necessary alternator shaft holding tool in. There is room to get the splined pulley removal tool into the pulley no problem, but you have no means of holding the alternator spindle still in order to release the pulley from the spindle (the spindle holding tool has to pass through the centre of the pulley removal tool, to do this it has to be sufficiently long to pass through the pulley tool and fully engage in the alternator spindle splines- a standard stubby spline socket is NOT long enough to do this, but the long splined socket I used for the task is too long to fit into the available space!).

(*-If anybody out there has managed to do this task without alternator removal on the Mk2 Galaxy, let me know and I will amend this article accordingly!)

With the alternator removed from the vehicle the actual process of removing & installing the pulley from/to the alternator is exactly the same as outlined below for the Touran, just make sure that you torque the new pulley up before refitting the alternator to the vehicle!



Unlike the Galaxy, on the Touran this procedure can be carried out without removing the alternator from the vehicle, simply because, due to the different chassis layout, there is more space to work in. Crucially, there is enough space to get the extended alternator spindle holding socket in.

Begin by pulling the large metal canister shaped fuel filter housing (arrowed red in the below image) up and out of it's retaining bracket. There is no need to disconnect any fuel lines. The filter housing is retained by 4 lugs on it's rear face into a pressed steel bracket and should dislodge with a firm pull upwards:

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Close up image of the top 2 lugs (circled yellow) below, they are retained by sprung metal 'arms' in the filter bracket:

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With the filter housing dislodged from the bracket, it can be swung out of the way and rested on top of the washer bottle filler neck as per the below image, there is now space to access the alternator pulley and belt tensioner:

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The plastic cap (arrowed orange in the below image) can now be removed from the alternator pulley- it just clips on, and will require a fine flat bladed screwdriver in order to gently lever it off. Also note the 4 cutouts (circled red) in the pressed steel bracket that locate & retain the fuel filter housing:

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With the cap removed, the auxiliary drive belt can now be removed from the alternator pulley only- do not remove it from any other pulleys! To do this, use the open end of a 16mm spanner on the lug on top of the belt tensioner and rotate the tensioner clockwise (as indicated by the red arrow in the below image). The tensioner can now either be 'locked off' by lining up the hole (arrowed blue in the below image) with a corresponding hole in the rear of the tensioner body (circled red in the second from last image down in this topic) and inserting a suitably sized pin/ nail/ allen key etc or just gently released (once the belt has been freed from the pulley) under spring tension until it reaches it's own backstop:

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With the belt clear, the 33 splined pulley removal tool can now be inserted to the pulley (the tool I purchased had a 22mm hex head- visible in the ring end of the spanner & arrowed orange in the below image- which is larger than on some of the pulley removal tools available- to me the larger hex head is preferable as the pulley was very tight on the spindle and the larger head allowed a larger spanner to be used and therefore more force to be applied). The spindle holding tool/ socket (arrowed green in the below image) can then be passed through the centre of the pulley removal tool (as per the below image) and engaged in the splined end of the alternator spindle. Said spindle holding tool must be long enough to pass through the pulley removal tool and fully engage in the alternator spindle. On the alternator fitted to the Touran that I carried out this procedure on, the spindle was splined to accept a 10mm 12 pointed male spline bit. I do not own one of these, but found a 10mm male XZN socket engaged snugly and did the job*^{(see note below)}. Using a ratchet in said socket to hold the alternator spindle still, anticlockwise force can be applied to the spanner to release the pulley from the spindle- it was very tight to crack off but once released span off with no further trouble:

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The below image shows the alternator spindle with the pulley removed (and the shaft holding spline profile):

(*- The 'XZN' profile is also known as 'triple square' - a 12 pointed outline, in effect, three squares overlaid on eachother and each one rotated 30^o relative to eachother. The 'teeth' of each of the 12 splines therefore have 90^o points. In contrast, the 'spline' profile, although also having 12 splines, does not have 90^o points, they are only 60^o. Therefore 'spline' and 'XZN' are not the same. The Wikepedia article here explains the differences better (along with drawings).

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With the old pulley removed, the new part can be fitted as a reverse of the removal procedure. The little leaflet supplied with the replacement pulley states that the pulley needs to be tightened up to a torque of 85Nm, which is fairly hefty. Obviously you can't torque it up via the spanner and splined removal tool, so you need to hold the spanner and splined removal tool (and therefore the pulley itself) steady whilst you use a torque wrench to rotate the XZN/ splined socket and alternator spindle anticlockwise (i.e, use the torque wrench in the opposite direction to normal!). Once the pulley is torqued up, spin it up by hand and check that the clutch is working properly, if all is well then you can clip the new plastic pulley cap onto the pulley and refit the auxiliary drive belt (ensuring that the belt is also correctly located in the grooves of the crankshaft and air con compressor pulleys, and that you remove the tensioner locking pin if you used one!) and the fuel filter housing to it's bracket, which just needs pushing down to secure once you've lined the 4 retaining lugs up in the retaining bracket holes.