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Old 20th January 2017, 16:28   #11
Hootbleet
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I'm going to put everything back together on Sunday. There'll be a fully charged battery going on to. Assuming there's a fault somewhere in the alternator, how many miles would I need to cover before checking the battery voltage? I'm assuming if all is working correctly and it's just a wiring fault triggering the dashboard light then there should be little to no voltage drop.

I hope I've explained that clearly 😂


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Old 20th January 2017, 20:46   #12
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At this time of year using lights, heater etc the battery will not last long even if it is in good condition internally.

Check the battery before you fit it to the car.

Make sure it has been off charge for at least 6 hours before you do this.

Fully charged you should see something like 12.6 volts or over.

You will see a dramatic change in two days of use if there is no charge going in to it.

When it's close to 12.2 volts you will have trouble starting the engine.
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Old 20th January 2017, 21:18   #13
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Quote:
Originally Posted by COLVERT View Post
At this time of year using lights, heater etc the battery will not last long even if it is in good condition internally.

Check the battery before you fit it to the car.

Make sure it has been off charge for at least 6 hours before you do this.

Fully charged you should see something like 12.6 volts or over.

You will see a dramatic change in two days of use if there is no charge going in to it.

When it's close to 12.2 volts you will have trouble starting the engine.
Thanks for that. A further question now if you don't mind. Presuming the althernator is at fault and the battery charging light illuminates. Roughly how many miles will I get before seeing the battery fail, and what will the battery voltage fall to?

Thanks again Jon
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Old 21st January 2017, 17:49   #14
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Thanks for that. A further question now if you don't mind. Presuming the althernator is at fault and the battery charging light illuminates. Roughly how many miles will I get before seeing the battery fail, and what will the battery voltage fall to?

Thanks again Jon
Now that is something very difficult to answer as it totally depends on how the car is used.----
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Old 22nd January 2017, 19:16   #15
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Refitted the regulator today, checked and cleaned up all the wiring. Tried 2 fully charged batteries and both started fine, then with the engine idling each battery started slowly dropping voltage, with the charging light on the dashboard very faintly flickering.

Is this more a sign of exactly what the problem is?
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Old 23rd January 2017, 11:59   #16
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With everything you have tried it is rapidly narrowing down to the need for a different alternator.---Sorry.
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Old 28th January 2017, 15:33   #17
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Been in Benidorm this week (lucky me eh!). Anyhow, back to reality ordered a new regulator from DMGRS this week and just fitted it this afternoon. Hands and feet are numb now.

The battery light is now mostly very dim, sometimes not on at all and sometimes fully lit. Previously the battery voltage was continually slowly dropping away, but it is now constantly holding above 14V. The car starts fine everytime, even with continual stopping and starting it on the drive. I've checked and cleaned the wiring from the terminal on the alternator, back to the starter, and then back to the battery terminal. Is there a connection I may have missed? All of the fuses are also fine, going to take it for a 30ish mile run tomorrow (which should be enough to show if the alternator is not doing its job). I'll take a spare battery in the boot just in case
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Old 28th January 2017, 16:46   #18
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Monitor the voltage using the OBD in 9.0 and see
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Old 28th January 2017, 17:52   #19
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Did you clean up the slip rings on the end of the alternator shaft Graham?, I did this earlier this week, using a red scotchbrite pad with a piece of cardboard to keep the debris from falling into the rectifier pack.

Looking at the brushes on your original AVR, they looked to be in decent order, compare to the ones I replaced on mine.....



The only other test you can carry out in situ, is to see if the stator windings are ok, you should have approximately .5 R across the two separate slip ring contacts, ie a virtual dead short circuit.

Also check fuse 14 in the passenger compartment fusebox, as this supplies the excitation voltage for the alternator

Brian
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Old 28th January 2017, 19:26   #20
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Quote:
Originally Posted by marinabrian View Post
Did you clean up the slip rings on the end of the alternator shaft Graham?, I did this earlier this week, using a red scotchbrite pad with a piece of cardboard to keep the debris from falling into the rectifier pack.

Looking at the brushes on your original AVR, they looked to be in decent order, compare to the ones I replaced on mine.....



The only other test you can carry out in situ, is to see if the stator windings are ok, you should have approximately .5 R across the two separate slip ring contacts, ie a virtual dead short circuit.

Also check fuse 14 in the passenger compartment fusebox, as this supplies the excitation voltage for the alternator

Brian
To be honest Brian, the slip rings looked almost new to me, but no I didn't attempt to clean them. One thing I have noticed is that the cover cap over the brushes was missing on the original brushes, and I'm not too sure I put one on when I changed the regulator either, dunno if that will make much difference, as the main cover is on the alternator.

Checked the fuses earlier and all were okay, I'll double check no.14 tomorrow. Been out on a couple of short runs tonight, battery light flickered faintly a couple of times. When starting the car the light does seem to take a bit longer to extinguish than previously
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