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John L

Alternator

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My original alternator a 15AC has died I think, is there a heat sink inside?  I see this part is no longer available, so it would make sense to fit a new 18 ACR.

The problem is that I am away from home, I need to order some parts to adapt the new alternator plug, and perhaps the wiring to the old control box on the wing, which I may be able to get from a LandRover dealer perhaps?

Could anybody tell me what I have to do to modify the wiring to accept the new alternator please.

Much appreciate any help please.

John

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John,

As an alternative:

I fitted a 55A Bosch alternator, comes from a Ford Fiesta (and others), no changes to the cnnector required.

I bough a Bosch remanufactured unit, not an aftermarket item, it cost me 80 euro.

Waldi

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Hi John, I replaced my Lucas 15 ACR about 18 years ago with an reconditioned 18 ACR (45 Amp output), at one of the local car parts retailers, think it was circa £35.

I dont think I had to replace/change any wiring or , or any electrical connections, it just plugged in. Here is a picture or the 18 ACR socket and my original connector. There is however another wire with a spade terminal that doesn`t go anywhere, but didn`t either with the 15 ACR?

Last week the 18 ACR packed up but replaced the two brushes, voltage regulator and Zener Diode puck (Lucas repair kit), and now its working perfectly. Such a simple repair.

Regards, Colin.

 

Lucas 18 ACR.JPG

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Thanks for the replies, now things have cooled down, its the battery that has actually shorted itself out, thats a relief, been and bought a calcium battery, so hope this should be an improvement. 

It was strange if I disconnected the earth wire from the battery it showed 12v, as soon as connected the earth wire it was down to only about 5 volts, and now ignition functions, had it tested  yes has volts but no amps.

Can I still use my battery condition charger on the calcium or do I have to get another charger for the future?

Perhaps I should consider uprating to the 18ACR when I get back home

I'm a long way from home at the moment in Moscow, so the battery was an easy fix.

John

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Your battery conditioner/charger will work just fine on the new battery John. 

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Your ammeter or voltmeter should show the condition of the alternator . Hope it was just the battery, vibration on a long trip can shake material off the plates in batteries nearing the end of their life.

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Thanks Mike I guess that could be the reason of its sudden failure, pity it was a Bosch battery only 5 years old, will have to see how the gel one gets on.

John

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Just had a quick drive around, the ammeter only shows a very little charge, but putting a voltmeter across the battery with the engine running and reving a bit its only showing battery voltage 12,5v, as its a new calcium battery is this what I should expect  see, or must I test out the alternator a bit more? 

Normally I see at least 13v with a lead acid battery when the engine is reved.

At this stage I don't really have a clue to prove if the alternator is working any help on testing points would be of a great help please.

PS  All I have is a multi meter but I don't think the amps function will not go high enough to check anything.

John

Edited by John L

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John,

first measure the battery voltage with the engine switched off. Then start the engine, and let it run ar 1500-2000 rpm just for half a minute or so, then measure the battery voltage again, while the engine is still running. It should be more than the first measurement. When the battery is fully charged (which may not be the case), you indeed measure around 13.5 V.

It is the alternator that determines the voltage, not the battery, but an empty battery will result in a lower voltage which goes up pretty quick once the battery is saturated (the alternatir can provide more current than a battery can absorb, hence the voltage rises).

Good luck,

Waldi

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And if the 2nd measurenent (engine running) is slower, even slightly, this indicates no charge, the battery is then unloading.

Waldi

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Waldi

As its a brand new battery, I don't think its lost anything yet.

After starting the ammeter rises about a good 1/4" or more into the + side, but the battery voltage doesn't seem to increase at the battery, but perhaps 0.1volt would this mean that the alternator is charging and I needn't worry about it?

John 

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A 'calcium' battery is lead-acid. It just has calcium alloyed on the lead electrodes instead of antimony.  The charging characteristic you see should be virtually the same as for your old one.  

If you are seeing a positive deflection on the ammeter then there is current flowing into the battery from the alternator. 1/4 inch deflection would be about 5 amps I would guess and just because it's a brand new battery doesn't necessarily mean it's fully charged.  (I am assuming here that the ammeter is wired the right way round and that it used to work that way with the old battery).

You should see that ammeter deflection drop off reasonably quickly if you keep the engine revving. If it stays there at the same level something isn't right.

Edited by RobH

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9 hours ago, John L said:

the battery voltage doesn't seem to increase at the battery, but perhaps 0.1volt would this mean that the alternator is charging and I needn't worry about it?

John 

Hi John,

if the voltage rises when the engine is running (compared to non-running and contact switched of), even by just 0.1 V, there is “some” charge. But not very convincing.

Another test you can do: with engine off, switch on the lights, heater motor, etc. And see how much the voltage drops. At that moment you are emptying the battery, so do this just for a short time.

Now start the engine (leave lights and heater on), and rev it a bit. If the voltage rises, your alternator is charging. If it rises above the “switched off voltage”, that’s a good sign.

But normally around 13.5 V is what you expect with running engine.

Regards,

Waldi

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Will just hope its ok,  another 740 miles to Helsinki via St Petersburg,  keeping my fingers crossed!

John

IMG_2444 (2).JPG

Edited by John L

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What a great trip John!

Run without consumers like lights, fan when possible, and measure the voltage after a couple of hrs. If not ok, have a 2nd charged battery (your old Bosch maybe) with you, so you won’t strand.

And enjoy the trip above all:)

Cheers,

Waldi

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Lights on are compulsory.....

Traded the old battery for the new...……...

John

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Completed 570kms today, even though the day and the date is not the best...….and the alternator seems to be back to normal, when reving it up, its up to 14 volts, and showing good position on the ammeter, needle just covering the + sign,  I still don't understand why I couldn't get that yesterday, it had me worried something else was also wrong.  That must be just to the new battery.

Thanks for the support its great to know I can get some answers even this far from home!

John

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Good news John, 

seems like you are back to normal. If you get 14 V, the alternator is certainly charging. It could be that the new battery was not fully charged and hence not “allowing” 14 V to be reached.

Enjoy the rest of the trip.

Waldi

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