How hard is it to do the bottom crank pulley on an 03 C5 hdi

[stu9]

Just that

Is it average home mechanic doable or no chance, when I say average, I can do some things, but not a c/head or gearbox

[Peter.N.]

Not at all difficult once you have removed the belt, getting the bolt undone can present a problem but if you put a socket on a long flexy bar with the end resting on the ground in front of the engine and just give the starter a blip, that usually undoes it nicely. The key that locks the pully also locks the camshaft drive sprocket so make sure it is still in position.

Peter

[stu9]

Ok....how hard/easy is to get the fan belt off

Do I need this key thing to lock the cam sprocket....where do I get it if I need it

[Peter.N.]

The tensioner has a bolt with a left hand thread in the centre, you need to get a long spanner or one with a tube over it to increase leverage and turn it anti clockwise, as if you were undoing a normal bolt, this will release the tension on the belt. Towards the back edge of the tensioner there are two small holes, if you push a drill or suitable sized rod into one of them, you need at least three hands to do this, it will lock the tensioner off so you can remove the belt. Before you do make a note of how its fitted, its very easy to get confused.

Peter

[RichardW]

A C5 will use the floating crank pulley, and therefore you should lock the crank and cam before removing the bolt. In practice (and what I think Peter did ) you will get away with unbolting it - the slop in the crank sprocket is small. I would still be tempted to use a crank locking device on the ring gear to undo the bolt, rather than relying on the brakes, which involves a fair amount of transmission wind up before it gets hold. If it's not been out before then you need a long breaker bar, or better still a windy gun, as that makes life easy (and you run less of a risk of upsetting the timing).