Strange vibration noise when hard lock steering left

[malcsj1]

I have seen several posts, but none that quite pinpoint my problem.
I first notice a problem a few weeks ago when pulling into my driveway turning in left, and a strange vibration noise coming from front of car. Its only on the left side, and seems to only occur after driving a mile or so.
Noise only occurs when moving, and does not sound like screach of a slipping belt.
I checked under the car and noticed inner CV joint gaiter had all grease around it, so got garage (at great expense) to replace, thinking this was the problem. Seemed to be ok when I drove home, but noise has re-appeared
Seems only to occur when warm, as I was in car park, driving round in circles (left and right) and could not reproduce the noise. Car has done 95k miles. Any ideas on what simple checks I can do, to get a better understanding what the problem might be?

[barlidge]

If you haven't done so already the first thing to eliminate would be the alternator pulley. I know it doesn't sound as though it would be the likely culprit it often can be.  It should free wheel in one direction but not the other, I'm sure there's a guide on here in the library.

[malcsj1]

Ok, missed your reply, but I went out to buy a new drive belt, as the original looked a bit cracked, so thought I would get a replacement. (none in stock, so ordered). I did ask about alternator pulley and was going to be another Ã,£60 +vat (with discount) so did not buy today. Slackened off belt, and alternator pulley does rotate in both directions turning alternator , when I press on belt on top of pulley. Wonder why it makes a noise, and what harm does it do turning in both directions, but will probably replace it anyway, and see if it fixes it. Did another carpark test, and noise happens on both left and right lock, but more pronounced on left lock.
Thanks for your advice, and I'll update with any progress but probably next week now.

[Chrispb]

When you say you can turn the pulley both ways with the belt removed that is correct now what you need to do is carefully through the slots  in the alternator casing is prevent the fan blade turning using a flat screwdriver while turning the pulley, you should be able to turn the pulley to the left (anticlock) but not to the right (clockwise).
If you cant turn the pulley to the left then the clutch has seized in the pulley.

[barlidge]

Sorry I may not have described it very well, when you spin the pulley in one direction it SHOULD spin the alternator, but in the opposite direction it should free-wheel, stopping the alternator spinning by gently putting something non metalic in the fan baldes can help diagnose this.

If its solid in both directions then its seized and can cause your symptoms.

[barlidge]

Chrispb beat me to it lol!

[malcsj1]

Doh! Yes I just looked up the library post on how to change the alternator, as I think the cost of the pulley (ok its a genuine Ford one) is not far short of the cost of a new alternator (on line, not Ford) which includes a freewheel pulley.
I also saw the instruction on how to use a nail  once the tensioner is pulled right back, and lock it off, Very handy!
So yes, it does spin feely in one direction and not in the other with alternator locked off with a screwdriver.
However I did carefully spray some WD40 behind the pulley (not on belt), and could not re-produce the noise when I went for a test drive. I suspect this is only a temporary fix. As the car is 95k miles old, replacing the alternator with a new one wouldn't be a bad thing I guess, but are these online makes any good? RTX was the one I saw.

[barlidge]

Hopefully you solved it then, if it does return can you note if the vibration is there when stationary and rotating lock to lock.

[malcsj1]

Ok fitted new drive belt and new alternator and unfortunately noise is still there. 
I took off tensioner to make access easier. Is surface that contacts with the belt supposed to be smooth?
Noise is not there when stationary, turning full lock. Left to right and back.
Does not seem to be brake related, as I am not applying brakes when noise occurs.
Noise comes after a couple of miles driving and is an irritation but will just live with it for a bit.
Alternator library guide was good, just struggled with getting the 2 wire connector off, as was not obvious how it came apart.

[insanitybeard]

When you say the inner CV boot was split, was it just the boot or the complete joint that was replaced? What you describe sounds like a CV joint on it's way out, especially if it's only occurring on one lock. Have you checked the condition of the front suspension arm bushes/ retaining bolts etc for condition and tightness? Not sure if knackered front suspension top mounts/bearings could cause the symptoms you describe but I know they can give trouble. And it may be worth checking the lower arm ball joints for that matter. If you can get both front wheels off of the ground so you can move the steering freely lock to lock and check for roughness that would be a good place to start.