simmosimkins
Member
Hope someone can shed some light.
My car is a 2200tc with a rebuilt starter motor, acr18 alternator, new battery, fan belt and new earth cables. With the battery fully charged we have a reading of 12.8 volts.
As expected the red ignition light comes on when you turn the key and goes out as soon as it fires. As soon as it fires the ammeter remains in the middle.
If you let it tick over, no sign of red light and battery has 12.9 volts. All good so far.
If you hold it at 2500 revs with nothing on we get 13.2 volts max , turn on the full beam down to 12.4-12.6, turn heater on as well and we are down to around 12 volts.
Does anyone know what is going on. If the battery is fully charged I can understand the current to the battery been regulated to the battery but surely only until after the voltage to the battery starts to push the 14 volt mark.
On the plug in volt reader I have never seen more than 13.5 volts with everything off, mostly around 13.2. This decreases as soon as load is applied. On my other 3 cars, there is always 14-14.4 volts, no matter what you are doing!
The question is this, is the alternator or voltage regulator not working properly? Firstly can the voltage regulator be adjusted to let more current through or are they a sealed part, or is the 18acr at 45 amps simply not capable of generating any more power than it does, in effect limiting the battery to a max charge of 13.5 but most often 13.2 with no load, in other words barley charging and discharging as soon as anything is put on.
I am not discounting the fact that I might have I been silly and should have bought a higher output alternator to begin with. If this is the case, feel free to suggest a suitable alternative, I wont be offended, just corrected
At best whilst driving I have no discharge (on ammeter or digital voltage readout plugged into fag lighter) once the lights/heater go on I have discharge at any speed and the voltage reader slowly drops towards 12.0 volts. Obviously the battery is becoming flat. So is the 18acr (in standard form) unable to keep up with consumption or the regulator not behaving as it should. We all know how the current situation ends up next day when you try and start the car!
Try as I might I cant see Rover selling these cars with the advice of "don't use the lights for more than a few minutes, especially the high beam, in case you flatten your battery!"
You can see what I have already replaced, if there are any helpful suggestions, please do not hold back, I am at the end of my rope with this one!!
My car is a 2200tc with a rebuilt starter motor, acr18 alternator, new battery, fan belt and new earth cables. With the battery fully charged we have a reading of 12.8 volts.
As expected the red ignition light comes on when you turn the key and goes out as soon as it fires. As soon as it fires the ammeter remains in the middle.
If you let it tick over, no sign of red light and battery has 12.9 volts. All good so far.
If you hold it at 2500 revs with nothing on we get 13.2 volts max , turn on the full beam down to 12.4-12.6, turn heater on as well and we are down to around 12 volts.
Does anyone know what is going on. If the battery is fully charged I can understand the current to the battery been regulated to the battery but surely only until after the voltage to the battery starts to push the 14 volt mark.
On the plug in volt reader I have never seen more than 13.5 volts with everything off, mostly around 13.2. This decreases as soon as load is applied. On my other 3 cars, there is always 14-14.4 volts, no matter what you are doing!
The question is this, is the alternator or voltage regulator not working properly? Firstly can the voltage regulator be adjusted to let more current through or are they a sealed part, or is the 18acr at 45 amps simply not capable of generating any more power than it does, in effect limiting the battery to a max charge of 13.5 but most often 13.2 with no load, in other words barley charging and discharging as soon as anything is put on.
I am not discounting the fact that I might have I been silly and should have bought a higher output alternator to begin with. If this is the case, feel free to suggest a suitable alternative, I wont be offended, just corrected
At best whilst driving I have no discharge (on ammeter or digital voltage readout plugged into fag lighter) once the lights/heater go on I have discharge at any speed and the voltage reader slowly drops towards 12.0 volts. Obviously the battery is becoming flat. So is the 18acr (in standard form) unable to keep up with consumption or the regulator not behaving as it should. We all know how the current situation ends up next day when you try and start the car!
Try as I might I cant see Rover selling these cars with the advice of "don't use the lights for more than a few minutes, especially the high beam, in case you flatten your battery!"
You can see what I have already replaced, if there are any helpful suggestions, please do not hold back, I am at the end of my rope with this one!!
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