Alternator is driving me nuts
Discussion
A few weeks ago, I finished a thorough refresh on my 99 Chimaera 450.
I replaced springs, dampers, tires, discs and pads, hood, carpets, radiator, valley gasket, inlet trumpets, induction kit, etc.
After my first drive of about 2 hours, my battery ran out of juice.
I managed to bring the car home, recharged the battery, and decided to replace the alternator as well.
After 2-3 weeks I managed to find some time to replace the alternator, and at that time the voltage was at the same level than 2 weeks before, when I had disconnected the battery charger.
After I had installed the new alternator, I went for a drive, and after 2 hours the same thing happened.
I suspected the 100 amp fuse, but upon inspection it seemed to be as new. Took the fuse out anyway and connected both wires on the same terminal.
Did some more testing today and I can't find any reason why it doesn't work.
Alternator light lites when ignition is turned on and goes out when the engine runs.
Voltage reading is exactly the same whit or whitout the engine running, so the alternator doesn't charge, not even when I rev it.
I do hear a subtle humming noise coming from the alternator when I turn on the ignition whitout starting the engine.
Sound is a bit similar to a computer cooling fan.
Any ideas?
I replaced springs, dampers, tires, discs and pads, hood, carpets, radiator, valley gasket, inlet trumpets, induction kit, etc.
After my first drive of about 2 hours, my battery ran out of juice.
I managed to bring the car home, recharged the battery, and decided to replace the alternator as well.
After 2-3 weeks I managed to find some time to replace the alternator, and at that time the voltage was at the same level than 2 weeks before, when I had disconnected the battery charger.
After I had installed the new alternator, I went for a drive, and after 2 hours the same thing happened.
I suspected the 100 amp fuse, but upon inspection it seemed to be as new. Took the fuse out anyway and connected both wires on the same terminal.
Did some more testing today and I can't find any reason why it doesn't work.
Alternator light lites when ignition is turned on and goes out when the engine runs.
Voltage reading is exactly the same whit or whitout the engine running, so the alternator doesn't charge, not even when I rev it.
I do hear a subtle humming noise coming from the alternator when I turn on the ignition whitout starting the engine.
Sound is a bit similar to a computer cooling fan.
Any ideas?
MADMAX2 said:
its not one of your fans permanently on?
No... thought of that too, but I unplugged them and got the same result. phillpot said:
Duff alternator.
Did you keep the old 'un?
I still have the old one and it is of course possible that the new one doesn't work as well, but the symptoms are exactly the same, and that made me think this is caused by something else.Did you keep the old 'un?
Don't have a clue what it could be, so opened a topic.
shake n bake said:
I had a similar issue a month or two back, mine turned out to be the warning light bulb was intermittently losing it's connection and so breaking the charging circuit.
Yours sounds like the alternator is at fault if you're getting no voltage out the back of it.
Do you mean the warning light didn't light up? Mine does, and I was wondering if it can if there's no proper connection. Wouldn't make sense to me, but at this point, I'm willing to believe anything :-)Yours sounds like the alternator is at fault if you're getting no voltage out the back of it.
Just to be sure on both the wring and the alternator, lets do a simple test.
engine off, multimeter on 20 volt scale, try to find a voltage at the back of the alternator. Its the hole at the rear, visible from the passenger side of the car. Should be 12+ volts. If 0, you have a break in the wiring somewhere. I have heard of it getting fried where it passes over the gearbox, between the 100 amp fuse and the battery. That would be enough to stop it charging.
Start the engine, test voltage in the same place. No different? Alternator not producing a charge. Either duff in some way, or belt slipping - see if the alternator pulley is turning. Or you have wired it incorrectly. Let me know if you suspect this and I will take mine off and photograph how it is connected.
What route does your belt take? From the power steering pump, it should go down to the big smooth pulley, up to the alternator, 120 degree turn, round the tensioner, down to the crankshaft pulley, up to the power steering pump. It is possible to fit the belt a different way, ie power steering pump to alternator to tensioner, then round the smooth pulley, but that can give too little pressure on the alternator. Is your tensioner pretty hard to force open enough to remove the pulley? Did you retighten the bolt under the tensioner after refitting the belt?
Photos to follow.
engine off, multimeter on 20 volt scale, try to find a voltage at the back of the alternator. Its the hole at the rear, visible from the passenger side of the car. Should be 12+ volts. If 0, you have a break in the wiring somewhere. I have heard of it getting fried where it passes over the gearbox, between the 100 amp fuse and the battery. That would be enough to stop it charging.
Start the engine, test voltage in the same place. No different? Alternator not producing a charge. Either duff in some way, or belt slipping - see if the alternator pulley is turning. Or you have wired it incorrectly. Let me know if you suspect this and I will take mine off and photograph how it is connected.
What route does your belt take? From the power steering pump, it should go down to the big smooth pulley, up to the alternator, 120 degree turn, round the tensioner, down to the crankshaft pulley, up to the power steering pump. It is possible to fit the belt a different way, ie power steering pump to alternator to tensioner, then round the smooth pulley, but that can give too little pressure on the alternator. Is your tensioner pretty hard to force open enough to remove the pulley? Did you retighten the bolt under the tensioner after refitting the belt?
Photos to follow.
71tuscan said:
MADMAX2 said:
its not one of your fans permanently on?
No... thought of that too, but I unplugged them and got the same result. phillpot said:
Duff alternator.
Did you keep the old 'un?
I still have the old one and it is of course possible that the new one doesn't work as well, but the symptoms are exactly the same, and that made me think this is caused by something else.Did you keep the old 'un?
Don't have a clue what it could be, so opened a topic.
shake n bake said:
I had a similar issue a month or two back, mine turned out to be the warning light bulb was intermittently losing it's connection and so breaking the charging circuit.
Yours sounds like the alternator is at fault if you're getting no voltage out the back of it.
Do you mean the warning light didn't light up? Mine does, and I was wondering if it can if there's no proper connection. Wouldn't make sense to me, but at this point, I'm willing to believe anything :-)Yours sounds like the alternator is at fault if you're getting no voltage out the back of it.
I'm no wiring expert but I learnt a lot tracing that fault!
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