Alternator Problem...Possibly AGAIN

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100BUR
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Alternator Problem...Possibly AGAIN

Post by 100BUR »

:oops: Hi All
I've fitted a new solid state requlator today, initial check and a couple of blast round the block everything looking good, temp up to normal, fuel gauge and all speedo warning lights working OK.

Next job reinstall the back inner dash cover against the bulkhead inside the car on the drives side, this is on my Elf before I can put the two glove boxes back in.

For anyone familiar with the Elf dash the center speedo is screwed in and the glove boxes attach to it.

First problem I can't remove the central speedo as one of the screws is totally rounded off, as the inner dash panel is only cardboard backed I thought I'd bend it a little to get it in after a bit of huffing and puffing it's back in, maybe not as good as when I first installed it but OK.
Glove boxes back in,as usual with a struggle.

Go to start and no ignition light,oil pressure light working.
On start up an unusual rattle.... it appears to me the alternator is ratterling, gets worse when I put the lights on main beam stalls the engine. I would expect the engine stall with the ECU I have fitted
The alternator and the battery are bran new about 20 miles if that.

My thinking is
I've pulled a wire off getting the dash panel in and not being able to see what I was doing.
The ignition bulb has blown
The new alternator is faulty.

All fault finding recommendations most appropriate :D
Last edited by 100BUR on Wed Mar 26, 2025 8:53 am, edited 1 time in total.
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Re: Alternator Problem...Possibly

Post by MagicWandWoody »

Ign on (engine off). Measure volts between the alternator energiser wire (unplugged from alternator) and ground. If not about 12V then bulb blown or wire come loose.

Engine on and rev it a bit for a moment (which will usually get any alternator to self-start, even without an energiser voltage, so long as there's not much load on it - lights and heater etc turned off). Measure volts at the battery. Expect around 14V if the alternator is generating. Expect about 12V if the alternator isn't.
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Re: Alternator Problem...Possibly

Post by 100BUR »

Thanks for the reply and info Woody

If I understand the ignition circuit correctly....
Also shorting to ground on the +12volts from the alternator to bulb,would also check if bulb is OK?
Cheers
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Re: Alternator Problem...Possibly

Post by 100BUR »

Ps
With the plug removed from the alternator :idea:
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Re: Alternator Problem...Possibly

Post by MagicWandWoody »

Yes, that'll work.
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Re: Alternator Problem...Possibly

Post by 100BUR »

I'm confused...

I've removed the alternator plug and have 12v to ground on the brown and yellow wire.

I made up a little cable with a couple of crimps put one in the plug onto the brown and yellow wire and the other onto the bonnet catch screw,checking continuity to the cars engine earth.
Switched the ignition on, still no ignition red light
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Re: Alternator Problem...Possibly

Post by MagicWandWoody »

As you first suspected, either the bulb is blown or a wire has come loose. Check at the IGN bulb itself: with ign on, one bulb contct should have 12V and (when the brown/yellow is grounded) the other contact of the bulb should be grounded.
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Re: Alternator Problem...Possibly

Post by 100BUR »

Thanks for getting back to me so quickly :D
I'm just attempting to get the dash out ...not easy with one of the screws rounded off.
I'll let you know how I get on.
Cheers
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Re: Alternator Problem...Possibly

Post by 100BUR »

Looks like I've sorted it :D

White wire into ignition light holder, had a very poor soldered joint with the fitment of a new bulb holder unit.
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Re: Alternator Problem...Possibly

Post by 100BUR »

I've remade the connection with inline crimps.

My AI assistant :D
informs me that crimping is better than soldering for automotive use and is what the major F1 teams use...
Technology :lol:
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Re: Alternator Problem...Possibly AGAIN

Post by 100BUR »

It appears the Alternator problem is back :(

When to start the car on Monday and the alternator is ratterling again and the ignition light is back on.

I went through a series of checks
Connections to bulb holder to and from
Fan belt
Cleanded Connection plug on alternator
Output wires to solenoid all appear to be OK
Checked fuse box Connection clean and secured
Measured voltage engine off and running, got the wife to give it some revs :D just ove12volts with no change.

I'm just a little surprised that a new alternator will fail after hardly any use ,couple of blasts up the dual carriage way.

When I went to see the car before I picked it up from its conversion, it had a similar problem, and a decision was made to fit a new alternator.

I'm assuming there's no other wiring issue and it's just a case of the new alternator failing, but I'm just a little uneasy with the same faults,appearing.

.
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Re: Alternator Problem...Possibly AGAIN

Post by Exminiman »

"I've fitted a new solid state requlator today," & "It appears the Alternator problem is back. When to start the car on Monday and the alternator is ratterling again and the ignition light is back on"

I may be missing something here but unless its very early you dont need a separate Regulator with an Alternator - the alternator has a built in regulator.
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Re: Alternator Problem...Possibly AGAIN

Post by 100BUR »

It's the requlator/stabiliser for the 10 volts for the temperature and fuel gauge I replaced :)

I think 🤔 one of the problems has been identified.

A friend of mine with many years in the motor trade and once chief engineer for a TVR race team popped round this morning, straight away he noticed very small metal fillings on the rad cowl, and said the pulley on the alternator is turning but not the shaft.
He was right

Disappointed with the new powerline alternator after hardly any use.

New alternator collected this afternoon, hopefully get it fitted on Friday
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Re: Alternator Problem...Possibly AGAIN

Post by hanlminiman »

100BUR wrote: Wed Mar 26, 2025 4:15 pm
A friend of mine with many years in the motor trade and once chief engineer for a TVR race team popped round this morning, straight away he noticed very small metal fillings on the rad cowl, and said the pulley on the alternator is turning but not the shaft.
He was right
I wonder if that fault would have been found with a 24 hour diagnostic computer check? :D
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Re: Alternator Problem...Possibly AGAIN

Post by 100BUR »

Very much doubt it :)
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