ive had a quick browse at alternator issues and have a fair idea of what im looking for but started a new thread as i havnt posted on here for quite a while as, number 1 i havnt had any issues and number 2 havnt done any mods lately.
so the problem
started car ok from cold no issue ,good weather warm not red hot ,approx a few minutes into journey of stops and starts 0-30mph pulled up to go around a parked car against a wall and heard what i thought was a lawn mower on other side, went to pull round noticed power steering had gone , looked down and noticed not charging light was on.managed to haul the car into a side street and turn around still running no issues just the not charging and power steering off(and an awful noise).
so was quicker to return to home before battery drained as suspected alternator goosed or belt had broke , life was restored in power steering and light went out just as i was joining back on main road and stayed ok to home.
popped bonnet and belt is still there , was replaced by me back in 2014(thanks to this forum tracing last post on belt number i posted on here 2014 pk6 1360)
it has signs of cracking on inner ribs as it goes over a pully but not terrible and about same as original belt(2006 so orig was 8 years old) i replaced for no issue but had had cambelt done so was time,ordered a belt yesterday.
so only just checked further today started again from cold no issue, no sounds or screeches rattles etc
battery voltage was a bit low 12.2v before cranking , but not unusually low for my car sometimes see 11.8v as low milage trips always(6-7mile).
so with car running voltage a good 14.05-14.01v
with lots of load high beams, rear heater,blower etc and air con was seeing 13.8v slowly dropping to 12.8v over 30 secs or so, i think then something must had dropped off as shot back up to near 14v could have been glow plugs(as i have extended afterglow in maps years ago)
so alternator not failed id say
battery on charge for now as not charged during summer weather
so plan is when it arrives old belt off feel pulleys on crank and alternator for issues and fit new belt and hope for the best , the noise is whats throwing me , very mechanical , then just stopped and went as normal and is now.
any thoughts welcome

Update
Battery not issue, just checked fully charged in just a couple of hours
Might have been winding window down or body computer waking up dropped that first voltage reading

well hopefully not too big an issue
belt off pulleys cleaned and spun bearings all feel ok plenty of life left, the tension roller for the aux belt still has plenty of oommph on the spring.
also the dampened crank pulley feels tight no sign of excess movement in the rubber cushion.
but considering this belt has only been on 4 years and i said it looked to be cracking similar to original 8 year old belt its actualy split accross and delaminated





hopefully this was the cause of the mechanical noise and not a consequence of something else going on.
just goes to show cant tell by looking(unless id wound engine round and checked every inch of it.
can only suspect it split and either jumped out of grooves and lost drive and re seated in v grooves or it got caught with a flap tucked and lost drive and then reseated
either way strange it reseated really and didnt throw the belt.
also incase this belt and new one are gates make

12.2v is rather low for a battery if you're often read that low voltage I'd day it's time for a new battery
Fyi 12.2 is around 50% charged

The belt doesn't look melted so I don't think it jammed, with the driven pulleys still spinning.. but that is a nasty looking bit of "falling apart".

It sounds like the belt was making the noises as it was still going round... but for a while at least it sounds like it was not turning the alternator at the normal speed.

The new belt should sort it... but you do need to run the beast on longer trips occasionally to keep the battery in good shape.

Ralf S.

just tidying this thread up
alternator ended up dying , not charging at all all sorted now replacement alternator
more details in this thread
https://www.fiatforum.com/stilo/462792-alterator-escape-route.html?p=4359663
but looks like that belt was damaged as a consequence of something starting to fail in alternator although very hard to say as was not new by any means.

If the pulley bearings were jamming then the belt might have been turning it but occasionally jamming on it...

But what make is it? It doesn't look heat (friction) damaged, as you might expect if the crank pulley was turning (as it must) but the alternator pulley wasn't.


Ralf S.