Alternator pulley sheared off!

A2Z

A2OC Donor
Bit of a nightmare today with the A2 unfortunately (but fairly lucky as it turned out as it could have been much worse).

As it's my son's 14th birthday today we thought we would have a sensible afternoon out for some fresh air and a change of scenery.

First I needed to pop to the post office so went in the A2 as that was what we had planned to use for the trip as it's much more economical than the other cars in the household.

Upon start up something just didn't sound quite right, a bit of belt squeal and slight dull groaning noise which soon seemed to ease. I thought about it for a second and thought it was probably just the v-belt or pulley a little dry as the car hasn't been used much recently so off to the post office I head.

All seemed ok but then when I started up again to come home same thing again.

Got home and said I don't like the sound of a noise with the A2 and so decided to go in the 3.0d instead although it would cost twice the price in fuel, turned out to be a good call!

Had a nice few hours out and when we got home plugged my code reader into the A2 and did a scan which revealed nothing untoward other than a couple of heater temperature/blower related codes.

Luckily a tyre garage I use were still open so I popped down and got the bonnet off to take a look.

When I drove in there was a loud worrying graunting noise, so quickly off with the bonnet to have a good look. Noise seemed to be coming from the v-belt area but couldn't rule out cambelt area so turned engine off, took off engine and cambelt covers to take a good look.

Fortunately cambelt looked fine and no evidence of any problems so checked all the pulleys for play and any rattling of which there was none, so started the car up again and was relieved to find cambelt tensioner and pulleys all quiet with the cover off so turned engine off again to put covers back on.

Started car again and revved it a little at which point I heard a bang and saw a puff of dust come out from the engine area, only to see the alternator /v-belt pulley rolling down the garage floor.

I was absolutely shocked that it could completely snap off and fly off the car like that, and to think what could have happened if we had made the trip in the A2 today and it happening on the road on the move rather than stationary in a garage doesn't really bear thinking about.

Anyway so now, does anyone know if the pulley is easy to replace or is it best to replace the alternator as well as I presume it would come complete and I'm pretty sure the alternator is the original to the car? Should I also replace the tensioner at the same time or is that overkill?

If anyone has a pulley or alternator available or knows what make or part numbers they are, that would be much appreciated.

I will also replace the belt itself although it didn't snap, so will need that too.

When I removed it I noticed it said Contitech on it along with the Audi rings so would like to keep that and all items original equipment brands unless there is anything better available?

Once I removed the belt the car started perfectly again and drove the mile or so home perfectly noise free, albeit with the battery light on but at least I can still say that an A2 has never left me stranded!

Car is a 53 plate TDI 75 with AMF.

Thanks guys ?
 

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There is a chance the alternator shaft has been damaged if the pulley has been spinning on it. Personally I would replace the whole alternator complete with a suitably rated one. Replacing the pulley / freewheel clutch is obvoiusly a cheaper option assuming the alternator is undamaged. Remember to replace the belt and tensioner at the same time. Cost up the parts and labour and take it from there.
 
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Although the A2 with the AMF engine was the first car to have a freewheel pulley on the alternator I believe it's a fairly common item these days.

Mine failed without warning, 400 miles from home on the Friday afternoon of a Bank Holiday weekend with an A2OC social starting 80 miles away that evening. Family on board, of course. It was just as we was were turning into a car park at Luss on the banks of Loch Lomond. We then got very lucky in that the RAC guy who recovered us knew a back street garage in Dumbarton a dozen miles back, where they might be able to sort us out for the next morning. Having helped us find a local hotel for the night he took the car away to drop it with them as we took a taxi to the hotel. Having checked in and just had a cup of tea, I got a phone call to say it was ready and they would come to collect me! They not only had the part on the shelf but also the special tool to remove and fit it with. We made the evening meal of the social at Fort William and even got a refund on the hotel room we no longer needed. The A2 gods were smiling on us that day I can tell you :)
 
Although the A2 with the AMF engine was the first car to have a freewheel pulley on the alternator I believe it's a fairly common item these days.

Mine failed without warning, 400 miles from home on the Friday afternoon of a Bank Holiday weekend with an A2OC social starting 80 miles away that evening. Family on board, of course. It was just as we was were turning into a car park at Luss on the banks of Loch Lomond. We then got very lucky in that the RAC guy who recovered us knew a back street garage in Dumbarton a dozen miles back, where they might be able to sort us out for the next morning. Having helped us find a local hotel for the night he took the car away to drop it with them as we took a taxi to the hotel. Having checked in and just had a cup of tea, I got a phone call to say it was ready and they would come to collect me! They not only had the part on the shelf but also the special tool to remove and fit it with. We made the evening meal of the social at Fort William and even got a refund on the hotel room we no longer needed. The A2 gods were smiling on us that day I can tell you :)
That's quite amazing and service you can only normally dream of.

Was the pulley anywhere to be found and did it or the belt do any other damage when it flew off (which I presume it did)?
 
There is a chance the alternator shaft has been damaged if the pulley has been spinning on it. Personally I would replace the whole alternator complete with a suitably rated one. Replacing the pulley / freewheel clutch is obvoiusly a cheaper option assuming the alternator is undamaged. Remember to replace the belt and tensioner at the same time. Cost up the parts and labour and take it from there.
I thought it might be a good idea to replace the tensioner at the same time for peace of mind and do the complete job as such.

Will look at prices and part numbers tomorrow ?

Will also see if I can check the AC compressor while the belt is off as the AC isn't blowing very cold atm. Hopefully it just needs a regass ?
 
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That's quite amazing and service you can only normally dream of.

Was the pulley anywhere to be found and did it or the belt do any other damage when it flew off (which I presume it did)?

It was fantastic service and a very reasonably priced job too. They got a good tip from me with my heartfelt thanks. Any further north up the loch though and I think we'd have lost most of the week we'd booked, and all of the social over that Bank Holiday weekend.

I heard the pulley drop off and hit the undertray, and I could see roller bearings down there when I took the bonnet off. The belt was still in place just with no tension and the battery light came on at anything above idle or with any electrics on. But no damage to the belt or alternator, both still working fine nearly 7000 miles later.
 
Here I have the 120Amp Alternator from my TDI AMF. The clutch puller is failing on it but I have a brand new, still in the bag an INA pulley. I also have the correct tool to change it. I’ll put it on the alternator in the morning and you can collect from Coalville LE67 when ever you’re able to do so. Order a new belt and you’ll be back on the road in no time.

Here’s the pulley I recently purchased and didn’t need as I collected one from ECP before this arrived. I kept it as a spare:
6BF1D034-6042-4AAF-BB15-F707ABCD42DF.png

Kind regards,

Tom
 
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It was fantastic service and a very reasonably priced job too. They got a good tip from me with my heartfelt thanks. Any further north up the loch though and I think we'd have lost most of the week we'd booked, and all of the social over that Bank Holiday weekend.

I heard the pulley drop off and hit the undertray, and I could see roller bearings down there when I took the bonnet off. The belt was still in place just with no tension and the battery light came on at anything above idle or with any electrics on. But no damage to the belt or alternator, both still working fine nearly 7000 miles later.
That's good to know that alternator was still good and undamaged.

I will have to look what special tools are needed to replace just the pulley as it might end up easier and not much more money to replace the alternator and pulley complete
 
Here I have the 120Amp Alternator from my TDI AMF. The clutch puller is failing on it but I have a brand new, still in the bag an INA pulley. I also have the correct tool to change it. I’ll put it on the alternator in the morning and you can collect from Coalville LE67 when ever you’re able to do so. Order a new belt and you’ll be back on the road in no time.

Kind regards,

Tom
Tom that sounds absolutely amazing!

Please let me know what you would like for it?
 
You’ll see in the picture Ive just added to post #7 that the pulley cost me £21.99 back in April. I’m certainly not wanting to be down anything on it as it is still sealed on the bag it came in. I think £10 for the alternator itself is surely a bargain. £32 and it’s yours to collect as I can only guess you’re not too far.

I can fit the pulley to the spare alternator in the morning ready for collection.

Happy to move to PM to swap address and phone number of need be.

Kind regards,

Tom
 
You’ll see in the picture Ive just added to post #7 that the pulley cost me £21.99 back in April. I’m certainly not wanting to be down anything on it as it is still sealed on the bag it came in. I think £10 for the alternator itself is surely a bargain. £32 and it’s yours to collect as I can only guess you’re not too far.

I can fit the pulley to the spare alternator in the morning ready for collection.

Happy to move to PM to swap address and phone number of need be.

Kind regards,

Tom
PM sent Tom ?
 
Having experienced the same a few months ago finally repaired last week, I have a couple of bits of advice.

1) If you've got a few days, get some penetrating fluid (WD40 or anything else suitable) on the two threaded inserts that the M8x85 alternator bolts are screwed into (at the right hand end of the alternator). It's a bit fiddly to spray the lower one, but a hell of a lot easier than removing the alternator when the lower bolt head shears off 5mm from the head after 2 turns (my alternator eventually took a plasma cutter to remove!).

2) Looking at the remains of the pulley, yours has not rounded off (it is square and open at the end ; on mine the open end had become conical and smaller than the Sealey 33-spline tool insert). Consequently you *should* be able to get the tool and insert into the splined part to remove the remains. Possibly in the car, but more likely off it. If you've been able to remove it in one piece, I would then send the alternator off for a refurb just in case - I planned to do this with my spare obtained from Ebay but Covid got in the way. Consequently I'm in the lap of the gods with the second-hand replacement alternator - although I have a new belt, tensioner and pulley I still worry that the alternator could go again - seems smooth enough though.

Best of luck - some lovely offers from the community above.
 
So I've just removed the tensioner and alternator which surprisingly was fairly straightforward and pretty easy.

I soaked the bolts in wd40 in every place possible and thankfully they all came out without a problem.

I was amazed to find that the belt is the original with the 2003 date on it and although in one piece, has some cracking so have ordered the only one I could find that is the correct 996mm long as the original where as all the other brands seem to now be 995mm, not sure if it would make any difference but would rather it be the same just to be sure. Just for reference it is a Dayco which I hope and presume is OE quality as I've been told. The original was Contitech and the OE part number off the belt is 045 903 137D model number 6 PK 996.

The tensioner roller also looks quite worn and a little out of round too so I will look at replacing that as well but the body of the tensioner itself looks fine, hopefully the roller itself can be bought separately as I see it just bolts on but if not I will just buy a new one complete.

My alternator is also the original and although nothing is wrong with it as far as I know, it is nearly 17 years old so common sense tells me that it's done amazingly well (much like the Varta batteries do) but obviously can't last forever, so while I'm at it I've decided that it's sensible to have it fully reconditioned and fit with a new genuine pulley at the same time so hopefully it will be good for another 17 years.

I have been recommended a company that does this and have spoke to the chap and liked very much what I heard so will give it a go. For reference my alternator is a Bosch 140amp not 120amp as the earlier models were (I presume it changed when they were facelifted in late 2002).

A big thank you again to Tom @2work for his very generous offer but obviously with mine being a 140amp it wouldn't be the right thing to put his old 120amp alternator on, as much as it would have saved me a lot of hassle.

Thanks also to everyone who has offered advice, it's very much appreciated and I will let you know how it goes.

All the best everyone ?
 
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As tempting Toms offer was, I do believe you are doing the right thing by replacing with a refurb 140A, the tensioner and belt. If you did not know , if the belt was refitted it had to go back on so that it traveled in the same direction, wrong way would cause the belt to fail very quickly due to being stretched against its memory.
 
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As tempting Toms offer was, I do believe you are doing the right thing by replacing with a refurb 140A, the tensioner and belt. If you did not know , if the belt was refitted it had to go back on so that it traveled in the same direction, wrong way would cause the belt to fail very quickly due to being stretched against its memory.
I think so too, well I certainly hope so anyway as I'm spending a lot more than I could if I went with Tom's pulley and fit it to my alternator. When I looked closely at the shaft it was quite worn looking and didn't look very even or true so I hope that it will have a new shaft when it's reconditioned.

The chap did mention that he keeps certain alternators on the shelf, already reconditioned ready to go on an exchange basis but I want to have my own done as I know it's had an easy life and belongs with the car.

Regarding the auxiliary belt, even if it didn't have any cracking at all I simply couldn't refit it knowing it's nearly 17 years old. It would appear that this is one of those items that gets neglected from being replaced during servicing, much like pollen and fuel filters, even at main dealers.

The new belt from ECP is only £6.83 plus vat which I was pleasantly surprised by ?
 
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Thought it might be a good idea to put a few photos up to show part numbers and the damage that can happen.

My advice would be to check if the auxiliary belt and alternator pulley especially has ever been changed and if not do it for peace of mind as this seems to be quite a common problem now as the cars are getting older and actually doesn't cost a lot of money if you buy the parts and fit them yourself. The tensioner roller would be a good idea too as you can see mine is worn although not unsafe.

It should also make the car run slightly smoother and quieter I would have thought?
 

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The picture of the shaft is the remnants of the pulley as if the pulley had completey come off you would see a threaded section at the end
 
Compare the images from A2Z above with mine below - in terms of how the pulley disintegration also rounded off the internals to prevent spline tool access - so this needed an alternator removal (and possible bench refurb - except the bolts sheared so it needed to be cut off and scrapped). This was at around 287,000 miles. I'd replaced the belt last November when it snapped, started noticing slight squeaks in December and Jan but the weather was so bad and daylight so short that I didn't have a chance to check it out at weekends until there was a terrible noise and it threw the belt (and pulley as it turned out) off into the undertray just after dropping my daughter to school in February. 3 months after Audifan (I think) here suggested checking the pulley. Finally got it fixed last week.
 

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>I have been recommended a company that does this and have spoke to the chap and liked very much what I heard so will give it a go. For >reference my alternator is a Bosch 140amp not 120amp as the earlier models were (I presume it changed when they were facelifted in late >2002).


If you could PM the recommended place that would be appreciated as I'm probably going to get another one done as part of this year's rebuild. I started looking into alternator rebuild places unfortunately about 4 days before the UK shutdown happened so ended up having to fit the non-rebuilt Ebay alternator to the car that needed it. Having had a set of petrol injectors refurbed with outstanding results I am very much of the 'make do and mend' mentality with some of these simpler components if one can find somewhere reliable.
 
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