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Discussion Starter #1 (Edited)
Last Saturday I broke down (well the car anyway). The symptoms were the ABS light came on, then the MIL, then the steering went heavy and my lights started dimming. Checked the voltage and it was down to about 7-8 Volts. No battery warning light and no charging. Nice RAC man lent me his battery pack so that I could drive the rest of the way home.

Well, after carrying out some voltage checks it was 95% certain that it was a knackered alternator. I was going to use the one off the VVC engine that I just bought, but it was different connections and I didn't want to start altering the car wiring.

I removed the old one and exchanged it for a re-manufactured one (Wallet is now best part of £200 lighter).

Here is how I did it.

If there is any doubt in your mind, disconnect the battery. However, on my TF there is an 80 Amp fuse just inside the engine bay, near where the two torsion bars come together. First you have to take off a plastic cover, and then the fuse just pulls out. If you don't do this then you can short out the alternator connection with the chassis causing damage to the car and maybe yourself



First of all you have take the rear roof and inspection panel off to gain access from the top. If you aren't sure how to do this look here http://forums.mg-rover.org/showthread.php?t=198762&highlight=30k+servicing

Next, jack up the car so that you can gain access from underneath. Remember to chock the front wheels and use axle stands for safety.



Remove the offside rear wheel and you will see a plastic cover between you and the engine. This is held on with about 3 plastic crosshead screws. Remove these and remove the plastic panel.



This will now give you access to the crankshaft pulley, alternator belt and two of the bolts that you need to undo.



You can also just see the alternator through the subframe



You can also see the offending alternator form above, through the inspection cover. This picture shows the belt removed, but we haven't got that far yet.



To give yourself more room, remove the heatshield from the exhaust. Obviously this will be hot if you have recently run the engine, so be careful. There is a 13mm nut and 2 10mm self tappers (one just out of view.



Loosen and remove the nut from the top securing bolt. Leave the bolt in for now.



Next, loosen the bolt that holds the adjuster bracket to the engine, from the wheelarch.

 

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Discussion Starter #2 (Edited)
Loosen and remove nut from the lower alternator securing bolt. Do not remove the bolt yet.



The alternator is now loose on the 3 securing bolts. You should now slacken off the 8mm adjusting bolt, shown here on a removed engine (no way to get the camera in on the car). This is best done from above by feel (you cannot see it) or from underneath the car.







Now remove the belt, remove the lower securing bolt from the alternator, and the adjuster bracket should now swivel down, free of the alternator.



You should now disconnect the main live cable, which is held on by a 13mm nut which is held captive on the cable crimp, so you cannot drop or lose it. Also dissengage and remove the plug at the top.



You now need to take the weight of the alternator and withdraw the top securing bolt. Warning...Once you remove this bolt the alternator could drop. In my case the alternator was still wedged in and needed a bit of waggling and levering before it came free. Now remove upwards and out.



Here you can see the loom with the two connections in. There are actually 3 connections as there are 2 in the plug. One is for the battery warning light, the other (I assume) is a live battery feed for excitation of the alternator. The battery warning light circuit is fed from fuse 25 in the fuse panel under the steering wheel. The excitation feed comes from god only knows where, as it isn't even shown on my circuit diagrams.



Here is the new alternator (Mmmm, shiny). It did come with a new pulley fitted. A bit annoying as it took me ages to take the old pulley off so that I could exchange the alternator. It didn't come with the 8mm adjuster bolt, so remove that and keep if you are planning on going the exchange route.



Refitting is the reverse of removing. Lower the new alternator in place and refit the upper securing bolt. Screw on the nut but do not fully tighten at this point. Reconnect the electrical connections (a bit of copper grease on the nuts and bolts will help on removal and rust resistance)



Clip the lower bracket back over the 8mm adjuster screw and refit the lower bolt through the alternator, so that it protudes through the slot in the bracket. Refit the nut, but do not tighten at this stage.



Refit the belt and ensure that it is sitting correctly on both pulleys. Now tighten the 8mm adjuster screw until the correct tension is felt on the belt. I went for a couple of mm's movement up/down at the longest point. You can also twist the belt to get a feeling of how tight it is. There is probably a correct figure somewhere, but I have done a few belts in my time and tend to go by feel, which is difficult to put in words. Overtightening can cause more problems than undertightening, as you are putting a greater load on the bearings.

Once the belt is at a correct tension you can tighten the 3 alternator securing bolts. The upper bolt



The engine securing bolt



And the bottom alternator securing bolt



Your alternator is now fitted. Now to put the car back together. Don't forget to put the plastic cover back in the wheel arch.

 

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Discussion Starter #3
Put the wheel back on, but before putting the rest of the car back together, it might be worth checking that the alternator is charging OK. Don't forget to put the 80 Amp fuse back in the holder. I checked the battery voltage and it was 12.48 Volts. Started the car and.....It works. Woohoo.



Now you can put the rest of the car back together.

I would imagine that this process is the same for most F/TF models, but there will be minor differences. For example, the heat shields are different, I am not sure if the 80 Amp fuse is present in all models, and obviously the alternators are slightly different connections. Here is the connections on the F VVC engine that I have. As you can see it is 2 bolt on connections.



Hope this helps some people.

Usual stuff applies. Although I have tried to think of evreything you need, I can't be held responsible if you try this yourself and things go wrong.

A small chimney sweep type boy might come in handy. Especially if they happen to have 4 ft long arms with 4 elbows.
 

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Discussion Starter #5
No probs. I wonder how much this costs for an xpart garage to do. It cost me £188 for the alternator, but obviously I didn't have to pay labour, I would say at least 3 to 4 hours labour on top.
 

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It's the 8mm adjuster screw that's snapped on mine so that needs drilling out if it can be and a new one put in, other than that it's a new alternator cos it just won't tighten by hand now.

Top thread m8 :)
 

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Discussion Starter #7
Do you know what alternator it is? Mine was a bosch, but the VVC one that I have is a Rover/Magneti Marreli. It should be easy to drill and rethread though. I would replace with a bigger bolt.
 

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Do you know what alternator it is? Mine was a bosch, but the VVC one that I have is a Rover/Magneti Marreli. It should be easy to drill and rethread though. I would replace with a bigger bolt.
It's the same as yours, Bosch, it has the same plug.

yeah it's just weather or not i can get my crappy drill to drill it out and find my tap and die set to make the thread. plus it all takes time. it was rusted to hell so it just turned and snapped off. my main problem is time really
 

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Discussion Starter #9
I would have thought you could do it the old fashioned way, without the bolt. Just use a suitable lever to pull the alternator out so that the belt is tight and then tighten the bottom bolt. Should hold. I would have thought the hardest part is getting a suitable lever in, which is probably why the bolt is there.
 

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I would have thought you could do it the old fashioned way, without the bolt. Just use a suitable lever to pull the alternator out so that the belt is tight and then tighten the bottom bolt. Should hold. I would have thought the hardest part is getting a suitable lever in, which is probably why the bolt is there.
Believe me i've tried lol, that's how it's on now but i just can't get it any more than it is and it's still slipping.

i've had a jack wedged in there forcing it out and still the **** won't tighten. seriously the worst alternator i've ever tried to tighten/adjust. it really does need that screw
 

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brilliant CJJ, I'd give you rep as well but have to spread my lovin' around :). I'll soon have to create a CJJ section on my web site :lol:
 

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Discussion Starter #17
Well, just took the TF for a test drive to check for any rattles/bits falling off and it actually feels considerably quicker and smoother. Might be my imagination or there might be something in running your car at the right voltage :)
 

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Well, just took the TF for a test drive to check for any rattles/bits falling off and it actually feels considerably quicker and smoother. Might be my imagination or there might be something in running your car at the right voltage :)
I had a car years ago with a knackered alternator, meaning the batt was always dying cos of it, changed the alternator and the car ran like a dream compared to what it was like.
 

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I had a car years ago with a knackered alternator, meaning the batt was always dying cos of it, changed the alternator and the car ran like a dream compared to what it was like.
Sister of a friend of mine has an MGF and he car mostly sits in her garage and if she remembers starts it occasionally but she forgot for a while and took it out a few days ago after charging the battery for an hour or two as it was flat and it conked out and wouldnt restart ..Ign warning light was on apparently as well as another couple ( probably oil etc when it wouldn't start) .Got a neighbour to tow her to a local garage and my friend says she believes that it had a new alernator fitted and it cost £300 ( that might be inaccurate) .I poo-poo'd the cost but reading above it could well be that much
 

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Discussion Starter #20
Fairly easy to change an alternator in a normal front engined car, but not the TF. Not the most difficult job I've ever done, but the fact that you have to go in through the wheel arch and in through the top adds a bit of time to it.
 
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