There are many types of tensioner that the Haynes (and the internet) mention, especially since this engine is in so many other cars as well. The commonest ones are...
- Manual tensioner, by means of adjuster bolt which moves the whole alternator.
Spring loaded tensioner with a 3/8" hole in it. Put in 3/8" driver and turn to retract the tensioner.
Tensioner roller with a big nut on with a smaller Torx-headed screw inside it. Undo Torx screw half a turn, then undo big nut.
My particular Xsara doesn't have any of these. In the belt, it has:
- Crankshaft pulley
Two rollers. The bottom one has a plastic cap on and is an idler roller. The top one is the tensioner.
Start by taking off the plastic engine covers and disconnecting the battery negative cable (I don't usually bother but for this job, you should). Then proceed as follows:
1. Use a 13mm socket on the nut in the centre of the tensioner roller to retract the tensioner enough (push the socket handle/spanner back towards the windscreen - this will compress the tensioner spring) to slip the belt off the rollers and pulleys.
2. Remove the exhaust manifold heat shield to give yourself a bit more room to work. Four 10mm bolts.
3. Remove the PAS pump mounting bolts. It's retained by one 16mm nut on the right hand side, and two 6mm Allen bolts on the left hand side. These two are only accessible through the holes in the pulley. One is at the back and one is underneath. Once you've undone these, you'll be able to move the PAS pump around on its flexi hoses and get at the alternator without having to remove the PAS pump altogether.
4. Pop the plastic cap off the idler roller with a short, flat-bladed screwdriver or similar. It's easy to pop the cap off but it's a bugger to find a correctly sized screwdriver to get in there! You want something not more than 80mm long with a small flat blade on.
5. Remove the idler roller. It's held on by one 16mm nut in the middle.
6. Disconnect the electrical connections to the alternator - one fiddly black plastic connector (there's a locking tab you need to prise up) and one big cable (held on with a 13 or 14mm nut, under a round black rubber cover). This is why you should disconnect the battery first - that big cable is directly connected to the battery live. If you touch the body of the car with it, sparks will ensue.
7. Undo the alternator mounting bolts, bottom ones first. There are four:
- One at the bottom which was behind the idler roller that you've removed.
One on the exhaust side of the alternator at the bottom.
One at the top on the left hand side of the alternator.
One at the top on the right hand side of the alternator (quite close to the exhaust manifold).
8. Lift out the alternator. Replace with shiny new one. Refitting is the reverse of removal. Try and remember which way the belt went