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Alternator voltage drops almost entirely when batteries are earthed


JugaarLife

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Hi all,

Hoping someone may point out an obvious thing I'm missing here. I have checked previous posts, couldn't find anything relating exactly to this problem, but happy to be redirected if I've missed it. 

 

I have just bought the boat, so as it stands everything is as it was when I picked her up. She has a Unipoint 12V 70amp alternator, running through a Sterling Digital to Alternator Battery Charger, max alternator size 80amp. Had a split charge relay on my previous boat, so I'm unfamiliar with this set up, although it looks to be logical.

 

Alternator shows almost no voltage when the battery earth is connected. Disconnect the earth and 12.6V (or whatever the starter battery is at) shows. As soon as the earth is connected voltage drops to 0.4V (hence "almost nothing"). All of the above is when the engine is off, when running the alternator simply doesn't charge, but that's no surprise.

 

I didn't install these electrics, so I'll just describe them as they are. I'm stating the obvious with some stuff but as I haven't yet found the fault I'll just whack it all in. The batteries are earthed to a standard earth bar. Sterling unit is earthed to the same via the leisure battery. The starter earth runs to the same via the alternator body and starter battery. 

 

If I bypass the alternator and go directly through the leisure battery (and so to the earth bar) the starter earth no longer functions as an earth. Battery does nothing at all when trying to start. Connect back through the body of the alternator and she starts fine, but then the alternator has no voltage. The earth for the starter functions only if it runs via the alternator body, nowhere else. There is what really, really looks like a negative terminal on the alternator (I do believe it is one), but if I connect the earth wires here, it doesn't work - as if it's an open circuit, as with bypassing the alternator.

 

I have checked all connections and wiring between starter, leisure, Sterling unit and earth bar, and have found no resistance at all (ok, 0.1ohms at one point, I forget where now but this was so minimal I ignored it), the cabling appears to be in excellent condition. 

 

I feel like this could relate to the Sterling unit, but that's possibly because it's the unfamiliar component in the set up for me. I can't actually work out why it would be though, since everything still shares a common earth whether through the alternator or not. The circuit seems basically the same. I'm sure I've missed something blindingly obvious. My knowledge of electrics is fairly limited (sure it shows!), so I hope that's the case. Will be so happy to be put straight, as I'm stumped! The poor leisure batteries are unfortunately absolutely, absolutely flat. 4V or something. Not sure how long they've been like that for, so I'm not crazy hopeful about their future, but I'll pass under that low bridge when I come to it. 

 

Any advice gratefully received. 

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40 minutes ago, JugaarLife said:

Alternator shows almost no voltage when the battery earth is connected.

 

Right, I'm struggling with most of your post but this bit especially! 

 

Battery earth? Batteries don't need earthing, there is nothing to 'earth'. Do you mean the negative lead, perhaps? 

 

And what do you mean by "Alternator shows almost no voltage"? How do you know this? Alternators don't display their output voltage so what is it you looking at, to know this? Thanks.

 

 

 

 

Edited by MtB
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55 minutes ago, JugaarLife said:

Hi all,

Hoping someone may point out an obvious thing I'm missing here. I have checked previous posts, couldn't find anything relating exactly to this problem, but happy to be redirected if I've missed it. 

 

I have just bought the boat, so as it stands everything is as it was when I picked her up. She has a Unipoint 12V 70amp alternator, running through a Sterling Digital to Alternator Battery Charger, max alternator size 80amp. Had a split charge relay on my previous boat, so I'm unfamiliar with this set up, although it looks to be logical.

 

Alternator shows almost no voltage when the battery earth is connected. Disconnect the earth and 12.6V (or whatever the starter battery is at) shows. As soon as the earth is connected voltage drops to 0.4V (hence "almost nothing"). All of the above is when the engine is off, when running the alternator simply doesn't charge, but that's no surprise.

 

I didn't install these electrics, so I'll just describe them as they are. I'm stating the obvious with some stuff but as I haven't yet found the fault I'll just whack it all in. The batteries are earthed to a standard earth bar. Sterling unit is earthed to the same via the leisure battery. The starter earth runs to the same via the alternator body and starter battery. 

 

If I bypass the alternator and go directly through the leisure battery (and so to the earth bar) the starter earth no longer functions as an earth. Battery does nothing at all when trying to start. Connect back through the body of the alternator and she starts fine, but then the alternator has no voltage. The earth for the starter functions only if it runs via the alternator body, nowhere else. There is what really, really looks like a negative terminal on the alternator (I do believe it is one), but if I connect the earth wires here, it doesn't work - as if it's an open circuit, as with bypassing the alternator.

 

I have checked all connections and wiring between starter, leisure, Sterling unit and earth bar, and have found no resistance at all (ok, 0.1ohms at one point, I forget where now but this was so minimal I ignored it), the cabling appears to be in excellent condition. 

 

I feel like this could relate to the Sterling unit, but that's possibly because it's the unfamiliar component in the set up for me. I can't actually work out why it would be though, since everything still shares a common earth whether through the alternator or not. The circuit seems basically the same. I'm sure I've missed something blindingly obvious. My knowledge of electrics is fairly limited (sure it shows!), so I hope that's the case. Will be so happy to be put straight, as I'm stumped! The poor leisure batteries are unfortunately absolutely, absolutely flat. 4V or something. Not sure how long they've been like that for, so I'm not crazy hopeful about their future, but I'll pass under that low bridge when I come to it. 

 

Any advice gratefully received. 

You need to specify where you are measuring the voltage and with relation to what - ie there are 2 meter probes, where are you putting both of them?

I think perhaps one clue is that measuring voltages when no current is flowing can be deceptive. So for example if there was a really bad connection between alternator and the battery positive, when you put the meter on the alternator positive and the battery negative with the alternator negative disconnected, I might read 12.6v because the meter takes virtually zero current and no other current is flowing. But when you connect the alternator negative and make a circuit, the small current flowing into the alternator via the really bad (high resistance) connection causes all the voltage to be dropped and the meter now reads zero,

 

Another consideration is that an alternator needs field current to work, that current has to come from a battery in the first instance before the alternator becomes self-generating. If the battery is completely flat, even if the engine is somehow running, the alternator won’t work. I’m not sure how the Sterling A2B works exactly, but it may take the power it initially needs to work and to supply the field current, from the leisure battery. It is of course connected to the starter battery as well - it has an integral “split charge” function - so that could be the initial source of power. Not sure. But anyway since you have a severely abnormal situation - leisure batteries at 4v - perhaps this is the only reason why things aren’t working. Or at the very least, it will make fault finding much easier if one abnormal thing is eliminated.
 

I would therefore strongly suggest obtaining a battery that is in a reasonable state of charge. It doesn’t have to be a huge leisure battery, just a car battery for example. Take the flat 4v leisure batteries out of circuit and put the new battery in their place and see if this makes the system work.
If not take it from there with careful explanation of exactly what you are measuring. Remember, you know what you are measuring but we can only know if you tell us precisely.

Edited by nicknorman
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Where are you measuring the voltage? If the leisure negative is disconnected, there will be no voltage between leisure positive and the negative bus bar.

If the leisure bank is indeed dead flat, when the alternator tries to charge it, the voltage between alternator output and negative will be low. Not sure how low, as I've only been in a position to try it once, and I never measured the voltage, just checked that current was flowing.

 

As per previous posts, I'm not sure I understand what's happening, or where the volts are being measured.

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1 hour ago, Quattrodave said:

Yeah I'm struggling to understand what you mean too.  Can you post a circuit diagram, draw it out neatly on a bit of paper and take a pic of it? Have you got a part number for you charge controller?

Here you go. I'm sorry, I don't know the correct symbols for everything but I hope that gives an idea. Disconnect the negative cables between the batteries and a multimeter (negative probe on starter negative, positive probe on alternator positive) reads the same voltage as the starter battery. Connect them and it reads almost zero. 

 

I think the controller part number is Pro Alt C, from what I can see on the casing. Tried to upload a photo but file was too big. 

IMG_20220924_011205.jpg

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1 hour ago, nicknorman said:

You need to specify where you are measuring the voltage and with relation to what - ie there are 2 meter probes, where are you putting both of them?

I think perhaps one clue is that measuring voltages when no current is flowing can be deceptive. So for example if there was a really bad connection between alternator and the battery positive, when you put the meter on the alternator positive and the battery negative with the alternator negative disconnected, I might read 12.6v because the meter takes virtually zero current and no other current is flowing. But when you connect the alternator negative and make a circuit, the small current flowing into the alternator via the really bad (high resistance) connection causes all the voltage to be dropped and the meter now reads zero,

 

Another consideration is that an alternator needs field current to work, that current has to come from a battery in the first instance before the alternator becomes self-generating. If the battery is completely flat, even if the engine is somehow running, the alternator won’t work. I’m not sure how the Sterling A2B works exactly, but it may take the power it initially needs to work and to supply the field current, from the leisure battery. It is of course connected to the starter battery as well - it has an integral “split charge” function - so that could be the initial source of power. Not sure. But anyway since you have a severely abnormal situation - leisure batteries at 4v - perhaps this is the only reason why things aren’t working. Or at the very least, it will make fault finding much easier if one abnormal thing is eliminated.
 

I would therefore strongly suggest obtaining a battery that is in a reasonable state of charge. It doesn’t have to be a huge leisure battery, just a car battery for example. Take the flat 4v leisure batteries out of circuit and put the new battery in their place and see if this makes the system work.
If not take it from there with careful explanation of exactly what you are measuring. Remember, you know what you are measuring but we can only know if you tell us precisely.

" there are 2 meter probes, where are you putting both of them". Negative probe on starter negative terminal, positive probe on alternator positive terminal. 

 

"So for example if there was a really bad connection between alternator and the battery positive, when you put the meter on the alternator positive and the battery negative with the alternator negative disconnected, I might read 12.6v because the meter takes virtually zero current and no other current is flowing. But when you connect the alternator negative and make a circuit, the small current flowing into the alternator via the really bad (high resistance) connection causes all the voltage to be dropped and the meter now reads zero," 

I believe the connections are ok, as when I test the resistance (multimeter testing ohms, one probe at each connection) there are zero ohms. Correct me if I'm wrong here, though. 

 

"Another consideration is that an alternator needs field current to work, that current has to come from a battery in the first instance before the alternator becomes self-generating. If the battery is completely flat"

I see what you're saying here, but that battery isn't completely flat, the multimeter (used as before) reads 12.6V on both the battery and positive terminal on the alternator. I did pop this in the original post. 

 

"Remember, you know what you are measuring but we can only know if you tell us precisely"

Very fair point. 

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1 hour ago, Iain_S said:

Where are you measuring the voltage? If the leisure negative is disconnected, there will be no voltage between leisure positive and the negative bus bar.

If the leisure bank is indeed dead flat, when the alternator tries to charge it, the voltage between alternator output and negative will be low. Not sure how low, as I've only been in a position to try it once, and I never measured the voltage, just checked that current was flowing.

 

As per previous posts, I'm not sure I understand what's happening, or where the volts are being measured.

"Where are you measuring the voltage? If the leisure negative is disconnected, there will be no voltage between leisure positive and the negative bus bar."

I agree completely, this is exactly what's confusing me. I can see that the voltage from the starter battery is reaching the alternator positive terminal, but ONLY when I disconnect the negative cable between the starter and leisure batteries. Which makes no sense to me at all!

1 hour ago, Iain_S said:

Where are you measuring the voltage? If the leisure negative is disconnected, there will be no voltage between leisure positive and the negative bus bar.

If the leisure bank is indeed dead flat, when the alternator tries to charge it, the voltage between alternator output and negative will be low. Not sure how low, as I've only been in a position to try it once, and I never measured the voltage, just checked that current was flowing.

 

As per previous posts, I'm not sure I understand what's happening, or where the volts are being measured.

"If the leisure bank is indeed dead flat, when the alternator tries to charge it, the voltage between alternator output and negative will be low."

Yes, but the loss of voltage running to the alternator when negative cables are connected occurs when the engine is off. It's not the fact that the alternator isn't charging (I know it can't charge if it's not getting any voltage), it's the fact that it no longer gets voltage from the starter battery when the negative battery cables are connected. Apologies, it's difficult to explain this, because it's so damn odd! 

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Agree with needing to know exactly where the voltage probes are connected, or if it is the boat's voltmeter instrument where that is connected.

 

A comment. A Unipoint 50 amp alternator sounds as if it may be an A127 and if so there is no way the starer motor negative/earth should run to the alternator negative and then on to the start battery negative. The terminal and post are just too small and the start cable too large. Do it the other way, big thick battery negative lead to the starter negative connection and then a separate thinner cable(but still fat compared with most of the boat's wiring)  between the same starter connection and the alternator negative, but in most cases the alternator negative can be connected to an alternator mounting bolt.

 

Try your tests again with the A to B output terminals disconnected and insulated, just in case it is doing something very odd indeed.

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Thanks for the extra detail. The positive voltage from the batteries routes through the electronics in the Sterling unit. The Sterling unit’s electronics is expecting around 12v on both batteries, whereas your leisure battery is more or less totally flat. I think this is where the odd behaviour arises, you are seeing “non linear” effects of the electronics unable to work properly due to the very low battery voltage. It is all about what is happening inside the Sterling.

 

So I come back to replacing the leisure batteries with a battery that is at a reasonable state of charge, then I suspect it will all work.

 

Even then I wouldn’t necessarily expect to find 12v on the alternator until the engine is running, because the Sterling unit may well not feed 12v from the batteries back to the alternator, it only sends power the other way (from alternator to batteries). The Sterling unit manual specifically says there is a diode in the engine battery connection so engine battery voltage can’t route backwards to the alternator. It isn’t specific about the same for the leisure battery, but there is voltage boosting electronics so quite likely the same applies. So checking for voltage on the alternator terminal when the engine isn’t running, isn’t really going to tell you anything useful.

 

Edited by nicknorman
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Just one other thing, you show the ignition switch wiring through the warning light to alternator D+ but not where the source of that power is. Does it go to leisure battery or engine battery +?

 

And what is the behaviour of the warning light? The light should come on when the ignition is turned on, then go out when the engine is started and maybe revved a bit. If the light isn’t coming on, the alternator won’t work. Bulb not lighting up might be because it’s connected to the leisure battery + (which is flat) but if it connected to the starter battery + it should be lighting up and if not, there is a fault somewhere. Bottom line is that there needs to be a couple of volts or so on the alternator D+ terminal when the ignition is switched on, before starting, otherwise the alternator won’t start working.

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11 hours ago, JugaarLife said:

a Unipoint 12V 70amp alternator

 

 

I'm wondering if this is a typo for"Unipart", the brand British Leyland used for their extensive range of spare parts including alternators back in the 70s and 80s. If so, this is quite likely to be a Lucas A127.

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1 hour ago, MtB said:

I'm wondering if this is a typo for"Unipart", the brand British Leyland used for their extensive range of spare parts including alternators back in the 70s and 80s. If so, this is quite likely to be a Lucas A127.

 

Unipoint does seem to be a thing.

 

https://www.autodoc.co.uk/car-parts/alternator-10450/mf-unipoint?gadw=1&gclid=Cj0KCQjw1bqZBhDXARIsANTjCPJZFm8U7WkIRL69gGbFpc3usjL_Wb7pNh23NsP4YFSuzo6SeN3mbrAaAiKAEALw_wcB

 

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3 hours ago, Tony Brooks said:

Agree with needing to know exactly where the voltage probes are connected, or if it is the boat's voltmeter instrument where that is connected.

 

A comment. A Unipoint 50 amp alternator sounds as if it may be an A127 and if so there is no way the starer motor negative/earth should run to the alternator negative and then on to the start battery negative. The terminal and post are just too small and the start cable too large. Do it the other way, big thick battery negative lead to the starter negative connection and then a separate thinner cable(but still fat compared with most of the boat's wiring)  between the same starter connection and the alternator negative, but in most cases the alternator negative can be connected to an alternator mounting bolt.

 

Try your tests again with the A to B output terminals disconnected and insulated, just in case it is doing something very odd indeed.

 

3 hours ago, Tony Brooks said:

Agree with needing to know exactly where the voltage probes are connected, or if it is the boat's voltmeter instrument where that is connected.

 

A comment. A Unipoint 50 amp alternator sounds as if it may be an A127 and if so there is no way the starer motor negative/earth should run to the alternator negative and then on to the start battery negative. The terminal and post are just too small and the start cable too large. Do it the other way, big thick battery negative lead to the starter negative connection and then a separate thinner cable(but still fat compared with most of the boat's wiring)  between the same starter connection and the alternator negative, but in most cases the alternator negative can be connected to an alternator mounting bolt.

 

Try your tests again with the A to B output terminals disconnected and insulated, just in case it is doing something very odd indeed.

Yeah, I explained the whole thing terribly in my first post. I was tired and frustrated! Regret that slightly now! Also, this is all quite new to me, so I know I don't always use the correct terms.

 

A better attempt - alternator wasn't charging, so I checked all cables and connections, using a multimeter, either checking resistance to see if the wiring was good, or in the case of the alternator, I wanted to see if the voltage was a) the same as the leisure battery while the engine was off and b) if there was any increase in voltage when the engine was running. Used a multimeter, negative probe on negative starter terminal, positive probe on positive alternator terminal. What I discovered was that when the engine is off, the voltage at the alternator positive terminal drops to less than 1V when the negative cables between starter and leisure batteries are connected. This is the same whether they are connected at the alternator body, or bypassing the alternator. I don't have a starter motor (have Dyna start/hand crank connected directly to the starter battery, there is not a negative wire between the Dyna start and alternator). The two large, negative cables between the starter battery and leisure batteries were connected at the body of the alternator, large bolt onto the engine block. If, however I do bypass the alternator, and have the negative cable from the starter running straight to the negative leisure terminal (and onto the earth bar from there), the starter battery will not power the Dyna start. 

3 hours ago, nicknorman said:

Thanks for the extra detail. The positive voltage from the batteries routes through the electronics in the Sterling unit. The Sterling unit’s electronics is expecting around 12v on both batteries, whereas your leisure battery is more or less totally flat. I think this is where the odd behaviour arises, you are seeing “non linear” effects of the electronics unable to work properly due to the very low battery voltage. It is all about what is happening inside the Sterling.

 

So I come back to replacing the leisure batteries with a battery that is at a reasonable state of charge, then I suspect it will all work.

 

Even then I wouldn’t necessarily expect to find 12v on the alternator until the engine is running, because the Sterling unit may well not feed 12v from the batteries back to the alternator, it only sends power the other way (from alternator to batteries). The Sterling unit manual specifically says there is a diode in the engine battery connection so engine battery voltage can’t route backwards to the alternator. It isn’t specific about the same for the leisure battery, but there is voltage boosting electronics so quite likely the same applies. So checking for voltage on the alternator terminal when the engine isn’t running, isn’t really going to tell you anything useful.

 

Thank you, Nick Norman! That is useful info about the Sterling unit. I will try again with a healthy leisure. 

 

Back to the other point - voltage reading at the alternator positive terminal. The thing is, it IS showing more than 12V when those negative cables are disconnected, and almost nothing when they are connected. Could this also be simply because my leisures are dead? My god. I hope so!!!!!

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1 hour ago, MtB said:

 

 

I'm wondering if this is a typo for"Unipart", the brand British Leyland used for their extensive range of spare parts including alternators back in the 70s and 80s. If so, this is quite likely to be a Lucas A127.

Fair assumption (I just double checked myself!) but no, it is indeed a Unipoint. Not heard of them before myself.

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2 hours ago, Tracy D'arth said:

Is there a negative heavy lead to the engine block ( not the alternator) from the starter battery? From your description I doubt that it is connected.

Not directly to the engine block, no, but there is the heavy negative lead running via the alternator body (not a terminal on the alternator, but the big bolt at the top of the alternator, which does ultimately go to the engine block), to the leisure battery negative (and onto that earth bar). Would this be basically the same? 

3 hours ago, nicknorman said:

Just one other thing, you show the ignition switch wiring through the warning light to alternator D+ but not where the source of that power is. Does it go to leisure battery or engine battery +?

 

And what is the behaviour of the warning light? The light should come on when the ignition is turned on, then go out when the engine is started and maybe revved a bit. If the light isn’t coming on, the alternator won’t work. Bulb not lighting up might be because it’s connected to the leisure battery + (which is flat) but if it connected to the starter battery + it should be lighting up and if not, there is a fault somewhere. Bottom line is that there needs to be a couple of volts or so on the alternator D+ terminal when the ignition is switched on, before starting, otherwise the alternator won’t start working.

Ahhhh....yes. Ok, so the alternator light does not work. It is powered by the leisure batteries. I don't actually have an ignition, she's hand crank with Dyna start, but this is starting to make a bit more sense. I'm going to try with healthy leisures. Thank you, Nick Norman, very much. My brain just became a tiny bit less baffled. 

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3 minutes ago, JugaarLife said:

 

Yeah, I explained the whole thing terribly in my first post. I was tired and frustrated! Regret that slightly now! Also, this is all quite new to me, so I know I don't always use the correct terms.

 

A better attempt - alternator wasn't charging, so I checked all cables and connections, using a multimeter, either checking resistance to see if the wiring was good, or in the case of the alternator, I wanted to see if the voltage was a) the same as the leisure battery while the engine was off and b) if there was any increase in voltage when the engine was running. Used a multimeter, negative probe on negative starter terminal, positive probe on positive alternator terminal. What I discovered was that when the engine is off, the voltage at the alternator positive terminal drops to less than 1V when the negative cables between starter and leisure batteries are connected. This is the same whether they are connected at the alternator body, or bypassing the alternator. I don't have a starter motor (have Dyna start/hand crank connected directly to the starter battery, there is not a negative wire between the Dyna start and alternator). The two large, negative cables between the starter battery and leisure batteries were connected at the body of the alternator, large bolt onto the engine block. If, however I do bypass the alternator, and have the negative cable from the starter running straight to the negative leisure terminal (and onto the earth bar from there), the starter battery will not power the Dyna start. 

 

OK. Can we assume that you are using a hand help voltmeter with probes.

 

I think this is an old engine, and far from normal, and I feel it has been much modified over the years, so I am guessing. You seem to have two charging sources, the alternator and the dynostart. I think it very likely that the A to B was fitted in an attempt to overcome charging problems, most likely related to simply low output charging devices., If what Nick says is even half true then it is complicating things and making any fault finding difficult.

 

If you were closer to Reading I would have loved to come and see what I made of the problem, and from what Nick says it may not be a problem, but you are too far away.

 

I think the basic problem is that the alternator is not charging and in your attempts to fault find it you found what you posted.

 

I think the best advice I can give is to see which battery bank feeds the alternator charge light and then temporally connect its charging cable on the A to B to the A to B alternator input terminal. That will take the A to B out of the charging circuit. Then try starting and revving the engine. If the warning lamp does not illuminate when you turn the switch on then you need t find out why, it is very unlikely to charge with no warning lamp current to excite it. If it does not charge then the alternator is highly suspect. If it charges the A to B is suspect.

 

Try that and report back. A photo or two of the engine would be interesting as well.

14 minutes ago, JugaarLife said:

Not directly to the engine block, no, but there is the heavy negative lead running via the alternator body (not a terminal on the alternator, but the big bolt at the top of the alternator, which does ultimately go to the engine block), to the leisure battery negative (and onto that earth bar). Would this be basically the same? 

 

Yes

 

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24 minutes ago, JugaarLife said:

If, however I do bypass the alternator, and have the negative cable from the starter running straight to the negative leisure terminal (and onto the earth bar from there), the starter battery will not power the Dyna start. 

 

Dynostarts usually have a charging control box that also contains a relay to direct power to the actual start part of the machine. Whatever battery is used to power the dynostart probably needs its negative connection to both the dynostatr body and the control box so you may have broken the circuit to the control box negative.

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1 hour ago, Tony Brooks said:

 

Dynostarts usually have a charging control box that also contains a relay to direct power to the actual start part of the machine. Whatever battery is used to power the dynostart probably needs its negative connection to both the dynostatr body and the control box so you may have broken the circuit to the control box negative.

Yes, this part makes sense. I wasn't hugely surprised it didn't work with the negative cables disconnected. Very helpful posts Tony Brooks and Nick Norman, thank you. I'll report back shortly! Appreciate your help. And yes, I'll gladly post a pic of the engine. Prewar Lister JP1. 

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1 hour ago, Loddon said:

Could it be something really obtuse like an alternator that is -ve earth and a dynastart that is +ve earth. I have seen such systems on old engines before.😱

 

Definitely a possibility, but without being there I can't say more. That might explain why there seems to be a negative bus bar rather than everything gong to a battery negative. I suppose a reasonable question now would be: is the  negative bus bar insulated from the metal hull.

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7 hours ago, JugaarLife said:

Ok, so the alternator light does not work. It is powered by the leisure batteries. I don't actually have an ignition, she's hand crank with Dyna start, but this is starting to make a bit more sense. I'm going to try with healthy leisures. Thank you, Nick Norman, very much. My brain just became a tiny bit less baffled. 


ok so I suspect that once there is a decent voltage supply to the warning light, everything will work fine.

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1 hour ago, JugaarLife said:

Yes, is the answer to that one. It's on a plastic fitting, mounted on a wooden board. 

 

I think I have said all I can without a full engine and charging wiring diagram complete with terminal markings on the equipment. Go with what Nick says he is very hot on electronics.

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