Alternator issue? Or something else to check first...?

Sorry I think I misunderstood, I couldn't get it to pivot like in the video (to be fair I didn't try a breaker bar) so I just undid the whole tensioner and put it back on. It seems to be exactly where it was before, but I'll get a breaker bar on the nut like in the video tonight, and see if it works.

Cheers for your help, I'll update you when I've had a chance to check it works with some more leverage.

At a wild guess (and depending on the length of the spanner) you are probably looking at something like a 50lb pull required to move the tensioner, obviously less with a long breaker bar but don't be afraid to give it a good tug

You also need to look at where you position the spanner on the bolt as that will make a big difference in the force needed (all to do with leverage and mechanical advantage). Just position it at the same angle in the video.

I've got a 450mm breaker bar so I'll give it a go with that tonight (didn't get a chance yesterday). On my way to work the power steering seemed to be playing up... if had this for seconds at a time before, but only when I've gone through a big puddle or a ford.

It was totally dry today so I thought it could be the belt slipping, so I've bought a new belt tensioner as I'll need to sort it out before Friday.

From looking online, I'm starting to wonder if the belt is actually the problem.... Do you have any bright ideas I can check over tonight please?

There are two different belt lengths for the 300tdi, its all to do with the alternator pulley as there are two different sizes (about 50mm diameter and the other is about 60mm). Did the alternator that you fitted come with the pulley fitted and is it the same diameter as the one you removed? 60mm uses the longer belt and 50 the shorter. If you have the small pulley with the long belt then the tension will be reduced and be the cause of your PS issue if it is slipping.

I did read that, and check and the pulley sizes were the same with the same number of grooves. I can't hear it slipping at all, so I'm guessing it's all okay.

It appears that my PS only sometimes doesn't work, and is only at slow speeds.

I checked my PS fluid yesterday and if anything it appears too full. My guess is that maybe I have an air-bubble in the system, pushing the fluid up?

Is it easy to bleed the air out of the system? I will have a look on here for a 'how to' - but if you have any other suggestions they would be welcome.

Thanks for your help as always.

There is a bleed point on the top of the power steering box, look for the square black cover held on with 4 bolts (with what looks like a bolt in the middle)just behind the radiator on the left as you look at it. I don't think it will need bleeding as it normally does a good job by itself, if you do open it do it with the engine stopped, if it is running you will get a gush of oil plus all the spinning bits are a bit of a hazard. Just open it a bit and move the steering from lock to lock and watch the fluid coming out, as you may guess that is a two person job. If the level is too high just syphon some out of the reservoir

Excellent, I'll take a look at that tonight - thanks.

I had a little look through a manual I found online, and they're showing a way to bleed it via the fluid reservoir? I'll post back when I've had a look/decided what to try.

Thanks

Alternatively