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Breakdown, Parts, Repair

Breakdown: stop the charge…

Having waited and waited some more I’d been delighted when I got the 924S back…

For my first journey I took it work and then to buy some new tyres. Driving back to the office, post tyre fitting, I stopped in a queue at traffic lights and, as I pulled away, I noticed the battery light flicker.

I assumed the battery was a little under charged and that it would come good after some driving, so didn’t think much of it and returned to my work. Keen to get back behind the wheel I was out the door shortly after 5:30pm by which time the sun was just about set, but I had [sweet] pop-up headlights, so even darkness bought a smile to my face. A short distance into my journey and I noticed the volt meter was stuck at 12V, I assumed this was not a good sign so all non-essential services were shut down.

All went as normal until a few miles into my journey, out into the countryside, I was in a commuter convoy as the car started to stutter. A quick look at the volt meter and it was now down in the red. As I had cars fore and aft I killed the main beams, the volt reading shot up and the car surged forward, I was going to make it. About a mile later and it transpired I wouldn’t – the car was stuttering again and I had nothing else to give. My second proper journey and I’d broken down. Hazards on, I got out of the car, into the hedge and called the RAC man.

I informed friends of my plight and tweeted about it too. It was a comment by @FailCar that reminded me I had a camera with me. What better way to kill some time than try a few night shots.

Porsche 924S Night Shot 1

I wasn’t really high risk so it took a while for the RAC to get to me, that’s not a complaint, just how it is. It did allow me to experiment with boxes as tripods.

Slight addition: thanks to @PeterGriffithss who drove past as I was in my broken down state and came back to check on me.

Porsche 924S Night Shot 2

The RAC man arrived and I reported my findings. A few minutes later and the alternator was determined to be faulty. On the plus side, when the RAC man gave the alternator a little tap (hit it with a metal pole) the battery light came on, there was life in it yet!  With a jump start the engine fired and was charging the battery. The Peter Kaye-looking recover driver followed me as I drove home. There was one other incident, alternator fail, but same solution and soon the car was in the garage.

Following up on Twitter later that evening I mentioned I needed to replace my alternator when [Rob] @FistsOfHam suggested I look at getting mine refurbed, as he was going to do with his 944 project. I did some searching and the following morning made a call and got lucky, Burghfield Starter and Alternator Centre could do the job and were local. I prefer to work off of recommendations so called Hillcrest and Simon suggested the Burgfield lot too..

That weekend I took the alternator out of the car. In principal it is a simple job, start by removing the airbox, which is a fiddly task. Thankfully I had the forethought to spray all of the nuts and bolts with WD40 the night before which made the job a lot easier. Taking the airbox out exposed the alternator [right] which had clearly seen better days.

Porsche 924S Airbox Broken 924S Alternator in situ

The real challenge though was the alternator belt tensioner (below), partly as I had no idea what I was doing with it. The nuts were pretty much corroded together and one was quite badly worn where someone had removed it previously. But it did relent and I was able to get it out in time to get to Burghfield before they closed.

Porsche 924S Alternator tensioner

I dropped the alternator in for an assessment, this was on a Saturday an I had to wait until Monday for the quote. They called with two prices; to repair the fault and to refurb the alternator which would then be warrantied, £70 and £85 respectively (ex vat). It seemed a no brainer really, I went with the latter. By the end of that day the refurbed unit was ready for collection; new bearings and voltage regulator were the main job, plus a few others bits and a spruce up.

Below shows the before and after shots of the alternator, I also cleaned up the tensioner which was slightly corroded.

Alternator taken from Porsche 924S Refurbed Alternator from Porsche 924S

For completeness I also wanted to replace the damage nut on the tensioner. Again, not too easy; it is counter threaded – it threads in the opposite direction to a standard nuts, hard to get used to turning and very hard to find. After trying to source from a few places I eventually ordered from my local OPC, despite being carefully specced it was wrong, this seems to be the way with the 924S, slight differences from the 924 and 944 which leaves parts that should be right not fitting. Credit to AFN Porsche though, being a small value they didn’t charge me for the nuts. More searching online and eBay, ‘counter nut’ and ‘reverse nut’ found nothing, ‘lefthand nut’ found something – ordered and a perfect fit. Below left shows how it compares to the original. M10 17mm, for nut spotters.

Porsche 924S Alternator tensioner nut Porsche 924S Alternator plug move

The only slight issue refitting the alternator was a grommet that houses the main bolt holding the alternator to the engine, the grommet was sitting too proud, making it very difficult to attach seat alternator. Having been painted to the alternator body the grommet seemed unwilling to move. A brace [spanner] and G-clamps (shown above) soon had everything back in place. The alternator was back in the car and, as seen below left, making the engine look very dirty.

Refurbed 924S Alternator in situ Porsche 924S Alternator Charging

Thankfully the engine started and the volt meter shot up to a little under 14V, I know from the RAC chap’s voltage test off the back off the alternator that the volt meter in the car is pretty much on the money. I took the car for a three mile drive and all remained steady.

Naturally I would have preferred that there had not been a problem, but with a breakdown and recovery under my belt I now feel a lot more like a genuine [modern] classic car owner.


4 thoughts on “Breakdown: stop the charge…

  1. Totally missed this post and your Tweets at the time. I had a very similar experience with the alternator on my 968, although it was a bearing that had gone, not so much it’s ability to charge the battery. I did the same and also had it fully refurbished. At a fair whack above 85 quid though I must say…

    Posted by CarQuiz | March 14, 2012, 7:46 am
  2. “with a breakdown and recovery under my belt I now feel a lot more like a genuine [modern] classic car owner” – love this quote. Something we can all relate to.

    Great work on the blog. Loving your work, sir.

    Posted by MajorGav | March 22, 2012, 8:59 pm

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