Cost of rewiring

[Erik.narrowboat]

4 hours ago, Tony Brooks said:

I described to you many posts ago how to test your relay but if that is beyond you simply disconnect and insulate one of the thick wires. Take care not to let it or any tools you use touch metal while doing so. Once that is done the normal link between engine & domestic bank is broken so if the engine battery is then discharging into the domestics there is another fault.

 

I also gave you a link to instructions on using a multimeter.

 

Do not spend money on things unless you are sure they are faulty, you will probably need lots to replace faulty batteries! For now & until you get the charging & starting sorted I would not buy any more solar panels as the one you have (about half a sq. metre you said) is probably about 30 watts and should do for now but NOT if it is not connected to a controller

 

1. Carefully squeeze the female blade connectors that keep falling off so they are a tighter fit and replace.

2. When starter battery is charged (even take it to a garage and ask them to charge it for you) put it in place and connect the positive terminal.

3. Connect meter set to 20 volts DC on the domestic battery terminals. From what you say I expect it to read below 12V. Leave it connected.

4. While observing the meter put the engine battery negative terminal onto post and twist a little. The voltmeter reading should not alter. If it goes up you know there is another link between banks somewhere. If the reading stays the same you then know there is on link.

5 Without altering anything reconnect the thick lead to the split charge diode. If the voltmeter rises you know the relay is permanently closed so a  new one is needed. If the reading stays the same you know the relay is open.

 

To further test the relay if it tested as open:

 

6. Start and rev the engine. The voltmeter (on the domestic bank should rise but that will not prove the relay is working, it will just prove the alternator is working and is connected in some way to the domestic batteries so note the reading.

7. Stop engine and move the voltmeter to the engine battery

8. Restart and rev engine, note the meter reading. It should rise to pretty much the same reading that you got in 8 above.  If both readings are the same then the relay is working. If the reading on one battery did not rise when you revved the engine then the relay is stuck open.

 

I am still far from convinced that there is much wrong with the electrics apart from visually horrible wiring AND a dodgy set of domestic batteries that were probably sold to you with the boat. I get the impression that you have just bought the boat and have been having electrical problems ever since.

 

Once you prove to yourself the batteries are not discharging into each other then you can extend those cables and move onto the next problem but until you get to grips with using a meter you will always be paying out for silly electrical problems.

 

When you have done the above report back on what each step told you. The engine should then  start & run  reliably so we can move onto testing the alternator and domestic bank BUT that will only be an indicative test  without a high current ammeter - not the one on the multimeter.

 

 

 

Hi Tony,

 

I have been trying to wrap my head around how the while system works. I was indeed using the multimeter wrongly with the amps hole connected which is why I didn't measure anything previously. I now know how to use it.

 

Just to make sure I understand everything, in your first paragraph you say I disconnect one of the thigh wires. You mean disconnect from the relay?

 

And in step 4 you said: '. While observing the meter put the engine battery negative terminal onto post and twist a little'. What do you mean by post?

 

Otherwise everything seems really clear. I will try to go through the whole process and give the outcomes.

 

You are correct I just bought the boat and have been having these issues. It had a shoreline before so previous owners either didn't know or didn't care about the problem

[Tony Brooks]

Note - I w2rote 8 above, it should be 6 above.  I also managed to write on when it should read no

 

The relay will have two thick and two thin wires on it. The thick wires may be connected to the relay by large blade connections or by nut & stud. I don't know which but it does not matter. Just disconnect one of the thick wires and tape whatever type of terminal that is on the end up so it can't touch any metal. Any sticky tape apart from aluminium tape will do, Sealotape, insulating tape, masking tape will all be fine.

 

I think that your engine battery has two lead posts sticking out of the top where you connect the wires to with clamps.I assume that at present one or both the clamps are off these lead posts, otherwise if there is a fault the battery will be being discharged so is unlikely to charge up from solar. By the way until we know if you have a diode or controller between panel and battery its bets to disconnect the solar at about an hour before dusk & reconnect an hour or so after dawn.

 

So in step 4 I mean put the clamp on the end of the lead back on the negative post, push down and give it a twist to ensure a good contact.

 

Don't feel  bad about almost certainly wrecking the ammeter part of your meter, Its just about the most common mistake to make and I have been known to do it myself when rushing and changing from measuring amps to volts. As I said the 10 or 20 amp scale has limited use on boats.

 

Now you have confirmed this boat is new to you and that the previous owner kept in on a shoreline I am as certian as I can be without tests that the domestic bank has had it. I suspect they are massively reduced in capacity and one or more cells are shorting out. That would make it seem to you that something was discharging them buit time will tell once we sort the immediate problem..

[Erik.narrowboat]

I have gone through the first five steps. I measured 0 at the domestic bank from the start. I guess that makes it hard to say anything about the relay as it seems the batteries are just completely dead. I reckon they wouldn't discharge the starter battery even if there was a connection when they are so far down?

 

The starter battery remains at 11.78 volts. I disconnect the solar panel at night. I have try starting the engine, which resulted in some movement but no start. I assume the battery is not strong enough to start it now?

 

I looked at the relay and it had actually two thick cables and three thin ones. It that one too many or it doesn't matter?

I could in any case just buy a new relay, I reckon they are cheap. Could anyone recommend which one to buy, as the one I have is probably not even the right one. I went to two electrics/hardware stores that but they had no clue.

 

It feels like a little bit of progress that the engine at least tried to start so at least the ignition works. I guess it's a first step. I think the domestic bank indeed has always been poor which was marked by a shoreline.

[Tony Brooks]

Unless the domestic bank either have dirty battery terminals them measuring zero volts does NOT mean that can not discharge the engine battery. They may well try. Anyway with 11.8V on the engine battery - all but dead flat - and zero on the domestics with the relay connected and the engine not running tells us that the relay IS NOT permanently closed. In fact there is probably nothing wrong with it, even if it is technically low on   current carrying capacity.

 

You have to learn to differentiate between a single wire in a terminal and two wires in a terminal. I bet one of the small relay terminals has two wires connected to it. Without tracing the circuit I can not say why but can guess and that is probably fine as well.

 

NO you did not go through the first five steps. You missed the VITAL part of step 2 - "2. When starter battery is charged (even take it to a garage and ask them to charge it for you) put it in place and connect the positive terminal." You ignored the part in red and unfortunately I get rather tired of spending hours trying to help and then find all too often what I wrote has been ignored.

 

A fully charged 12V lead acid battery should have a terminal voltage of AT LEAST 12.7 volts and may well be higher. I am sure someone else pointed this out to you way back in the topic. Until you can get the start battery voltage up to around 12.5V first thing in the morning (having been off charge over night) there is very little hope of it ever starting the engine.

 

Now another list.

 

1. Go to any major supermarket and buy a large fibre reinforced grocery bag with fabric handles- about £2, NOT a flimsy polythene bag.

2. Take it to your boat.

3. Disconnect the start battery and undo any securing clamps.

4. Lift battery out and place in bag, keeping the battery upright.

5. Use yellow pages etc to locate a local car repair shop near you.

6. Phone said shop and ask if they can charge a battery for you.

7. if answer NO repeat steps 5 &6 until one says YES.

8. Carry battery to said shop and get it charged.

9. Get the battery back to boat and measure the voltage. If below about12.5 the battery is probably ruined. If above about 12.5 carry on.

10 Put battery in place and secure clamps.

11. Now got to  step 3 in my first list and carefully carry out the tests.

12. Report back but I bet the relay will turn out to be perfectly serviceable for now and until the rest of the problems are sorted.

 

You can but whatever you want but it seem silly to buy new parts like the relay before you have even tested them, Especially as you are looking at a new domestic battery bank at between £150 & £250 plus possibly a new engine battery but we will see about that in due time. When it is appropriate we will tell you where to buy a new relay from and it is NOT from ordinary shops.

 

One careful step at a time is the way to go unless you pee me off so much I give up on you but even then others on the forum may help.

 

 

e

[Erik.narrowboat]

Tony,

 

My apologies for neglecting part of your message. I can tell that you have put effort into making your instructions very clear and I should have followed them with equal precision. I will phone up garages tomorrow to get the battery charged and report back as soon as I can.

I really do appreciate your help. Although some things are a little over my head I have learned a great deal from you and am thankful for your input.

I hope you can forgive me for my impatience.

 

Best,

Erik

[Richard10002]

In Tonys last post you could get the carrier bag, go to a shop that sells batteries, buy a starter batter, (110 Ah £70-£100), take it back to the boat, and go straight to 10.

 

I know money doesnt grow on trees, but if you were considering an electricians quote of a few thousand pounds, even without an inverter, a hundred quid for a battery seems relatively small beer, given that it would get you to point 9 quickly.

[philjw]

10 hours ago, Richard10002 said:

In Tonys last post you could get the carrier bag, go to a shop that sells batteries, buy a starter batter,

If you do this, take your meter and test the voltage. They are not all fully charged off the shelf.

[MtB]

28 minutes ago, philjw said:

If you do this, take your meter and test the voltage. They are not all fully charged off the shelf.

 

Good suggestion. A new, properly charged battery ought to read 12.70 Volts.

 

If it reads lower, it has probably been on the shelf a long time and not charged or maintained. If it reads higher, it has probably only just been taken off charge before being brought out from the back for you to buy. Provided they didn't know in advance you were coming to buy a particular battery, this indicates at least they look after their stock. 

[Sea Dog]

17 hours ago, Tony Brooks said:

One careful step at a time is the way to go unless you pee me off so much I give up on you...

 

Tony's technical advice is undoubtedly priceless, but it's not his only priceless facet!  Nice one Tony! 

 

[TheBiscuits]

7 minutes ago, Sea Dog said:

Tony's technical advice is undoubtedly priceless, but it's not his only priceless facet!  Nice one Tony! 

"The customer is always right -  if they are not right they won't be a customer."

[Alan de Enfield]

1 minute ago, TheBiscuits said:

"The customer is always right -  if they are not right they won't be a customer."

But are you a customer if you are getting (what would be) expensive advice for free ?

[Tony Brooks]

Erik  - any up date on this or how you are getting on before I go boating for a while?

[Erik.narrowboat]

Quote

 

1. Carefully squeeze the female blade connectors that keep falling off so they are a tighter fit and replace.

2. When starter battery is charged (even take it to a garage and ask them to charge it for you) put it in place and connect the positive terminal.

3. Connect meter set to 20 volts DC on the domestic battery terminals. From what you say I expect it to read below 12V. Leave it connected.

4. While observing the meter put the engine battery negative terminal onto post and twist a little. The voltmeter reading should not alter. If it goes up you know there is another link between banks somewhere. If the reading stays the same you then know there is on link.

5 Without altering anything reconnect the thick lead to the split charge diode. If the voltmeter rises you know the relay is permanently closed so a  new one is needed. If the reading stays the same you know the relay is open.

 

To further test the relay if it tested as open:

 

6. Start and rev the engine. The voltmeter (on the domestic bank should rise but that will not prove the relay is working, it will just prove the alternator is working and is connected in some way to the domestic batteries so note the reading.

7. Stop engine and move the voltmeter to the engine battery

8. Restart and rev engine, note the meter reading. It should rise to pretty much the same reading that you got in 8 above.  If both readings are the same then the relay is working. If the reading on one battery did not rise when you revved the engine then the relay is stuck open.

 

I am still far from convinced that there is much wrong with the electrics apart from visually horrible wiring AND a dodgy set of domestic batteries that were probably sold to you with the boat. I get the impression that you have just bought the boat and have been having electrical problems ever since.

 

Once you prove to yourself the batteries are not discharging into each other then you can extend those cables and move onto the next problem but until you get to grips with using a meter you will always be paying out for silly electrical problems.

 

When you have done the above report back on what each step told you. The engine should then  start & run  reliably so we can move onto testing the alternator and domestic bank BUT that will only be an indicative test  without a high current ammeter - not the one on the multimeter.

 

I have taken the starter battery to the garage to charge it and now manage to start the engine reliably. My findings on the above:

3. The domestic batteries read 0.

4. The domestic batteries read 0, hence the voltmeter does not alter.

5. Again the voltmeter reads 0.

 

6. The voltmeter still reads 0.

8. The voltmeter reads 12.93, which is the same value I got with the engine switched off.

 

I hope this can give some information to move on to the next step. I have been moving the boat yesterday and the engine battery did have the same reading before and after (12.93). I am not sure if that means if has been charging since it was already (more than) full to begin with. 

 

I apologize for taking so long to get back. My parents came to visit which is rare because I live abroad so I wanted to spend time with them. It would be great if you can further advice me when you are back from boating.

 

Thank you

[Tony Brooks]

1 hour ago, Erik.narrowboat said:

I have taken the starter battery to the garage to charge it and now manage to start the engine reliably. My findings on the above:

3. The domestic batteries read 0.

4. The domestic batteries read 0, hence the voltmeter does not alter.

5. Again the voltmeter reads 0.

 

6. The voltmeter still reads 0.

8. The voltmeter reads 12.93, which is the same value I got with the engine switched off.

 

I hope this can give some information to move on to the next step. I have been moving the boat yesterday and the engine battery did have the same reading before and after (12.93). I am not sure if that means if has been charging since it was already (more than) full to begin with. 

 

I apologize for taking so long to get back. My parents came to visit which is rare because I live abroad so I wanted to spend time with them. It would be great if you can further advice me when you are back from boating.

 

Thank you

 

The first five tests tend to confirm there is no permanent connection between the engine and domestic systems and that the split charge relay does not have its contacts stuck together.

 

Test six suggest the split charge relay is not making contact so MIGHT be faulty

 

Test 7 & 8 suggests the alternator is not charging and this may be why the relay is not closing and why the batteries were flat.

 

Now the question is why is it not charging. I am going to assume its a common type of alternator like a Lucas A127 but a photo (if not already sent) of the back of the alternator may help identify it.

 

There will be one or two thick black wires. On connected to a terminal marked B+, the other, if there is one may be connected to the case or a terminal marked B-.

 

With the engine batteries connected and the master switch(es) turned on but the engine stationary connect a voltmeter pos to b+ and neg to B- or the alternator case. Expect battery voltage so about 12.6 or 12.7 by the time you get round to doing it or less if you have been using any electricity.  If it reads zero then there is a problem with either the B+ cable/connections or the B- cable/connections, so:

 

Voltmeter between B+ and engine battery neg. Expect battery voltage. If not the B+  cable/connections are faulty. Repeat between B- and the engine battery pos terminal. Again expect battery voltage and if zero the B- cable/connections are faulty. My hunch is the first test will be OK.

 

Now you will find one or two THIN wires on the alternator. Probably only one if you do not have a rev counter. The thin wire you are interested in goes to a terminal marked D+.   Because of teh split charge relay that terminal might have two thin wires on it.

 

Test;- turn the ignition on, does the  charge warning lamp light up?

 

If yes pull the wire(s) off the D+ terminal, does the light go out. If yes the alternator needs to go for overhaul.

 

If no still pull the D+ wires off and push the wire terminal onto clean metal like the alternator case. If the light lights up then the alternator is faulty (probably worn brushes). If no then the warning lamp bulb has blown or you have a wiring/connection problem between the ignition switch, warning lamp, and D+ terminal.

 

Let us know how you get on.

[Erik.narrowboat]

Thank you for your instructions. I will go through the different steps torture evening. I will also take a photo of the alternator to understand the connections.

 

Regarding the warning light bulb, this was indeed broken but replaced a couple of weeks ago. The wires seem loose though. I will also take pictures of that situation.

[TheBiscuits]

1 hour ago, Erik.narrowboat said:

I will go through the different steps torture evening.

It's not *that* hard to do

 

[Erik.narrowboat]

Haha, hopefully not

[Robbo]

10 hours ago, Tony Brooks said:

Test six suggest the split charge relay is not making contact so MIGHT be faulty

I’ve not followed the thread but if the relay is a voltage sensitive kind then they need to sense voltage on both sides to work, usually above 9v.

[Tony Brooks]

50 minutes ago, Robbo said:

I’ve not followed the thread but if the relay is a voltage sensitive kind then they need to sense voltage on both sides to work, usually above 9v.

Its not, we have seen a photo. Its a blue Lucas "caravan" relay.

[Tony Brooks]

9 hours ago, Erik.narrowboat said:

Thank you for your instructions. I will go through the different steps torture evening. I will also take a photo of the alternator to understand the connections.

 

Regarding the warning light bulb, this was indeed broken but replaced a couple of weeks ago. The wires seem loose though. I will also take pictures of that situation.

The bulb needs to be and absolute minimum of about 1.5 watts and 2.2 or 3 watts is better. If the light is an LED or grain of wheat (dolls house) bulb then it is unlikely to provide enough electricity to get the alternator charging. In that case I would prefer a larger wattage bulb but you can fix a resistor or another bulb in parallel with the small bulb/LED so it passes more current. If your lamp is one of the"push into the hole" types about 3/8" in diameter, about 1" long and you can't pull the bulb from the back to see  what it is then its almost certainly a grain of wheat bulb.

[Erik.narrowboat]

The bulbs I bought are similar to these ones, except that they are 12V 4W. The ones currently fitted are only 12V 2W.

https://www.halfords.com/motoring/bulbs-blades-batteries/car-bulbs/halfords-hbu380-21-5w-car-bulbs-x-2

[Erik.narrowboat]

I have taken some photos of the panel where the bulbs sit in, the wiring behind and of the alternator.

 

 

[Tony Brooks]

OK.Common as muck Lucas A127

 

The blue wire in the smaller 6mm blade is the D+ (warning lamp wire).

 

The two thick reds are on a pair of twined 9mm blades so both are B+

 

B- is the case so there is no B- terminal or wire.

 

It is hard to see but it looks, from the blue wire, that the lamp without a lens on is the charge warning lamp and the bulb looks as if it could well be a 2.2 watt MES or MCC bulb so that shoudl be OK for energising the alternator as long as it lights up with the ignition on and engine not running.

 

There is a brown wire right next to the blue one, if its in the same terminal (two cables into one 6mm female) then it is almost certainly running to and controls the split charge relay.

 

I strongly suspect the alternator has had it but do the last set to test I gave you and report back.

Edited August 21, 2018 by Tony Brooks

[Erik.narrowboat]

22 hours ago, Tony Brooks said:

 

The first five tests tend to confirm there is no permanent connection between the engine and domestic systems and that the split charge relay does not have its contacts stuck together.

 

Test six suggest the split charge relay is not making contact so MIGHT be faulty

 

Test 7 & 8 suggests the alternator is not charging and this may be why the relay is not closing and why the batteries were flat.

 

Now the question is why is it not charging. I am going to assume its a common type of alternator like a Lucas A127 but a photo (if not already sent) of the back of the alternator may help identify it.

 

There will be one or two thick black wires. On connected to a terminal marked B+, the other, if there is one may be connected to the case or a terminal marked B-.

 

With the engine batteries connected and the master switch(es) turned on but the engine stationary connect a voltmeter pos to b+ and neg to B- or the alternator case. Expect battery voltage so about 12.6 or 12.7 by the time you get round to doing it or less if you have been using any electricity.  If it reads zero then there is a problem with either the B+ cable/connections or the B- cable/connections, so:

 

Voltmeter between B+ and engine battery neg. Expect battery voltage. If not the B+  cable/connections are faulty. Repeat between B- and the engine battery pos terminal. Again expect battery voltage and if zero the B- cable/connections are faulty. My hunch is the first test will be OK.

 

Now you will find one or two THIN wires on the alternator. Probably only one if you do not have a rev counter. The thin wire you are interested in goes to a terminal marked D+.   Because of teh split charge relay that terminal might have two thin wires on it.

 

Test;- turn the ignition on, does the  charge warning lamp light up?

 

If yes pull the wire(s) off the D+ terminal, does the light go out. If yes the alternator needs to go for overhaul.

 

If no still pull the D+ wires off and push the wire terminal onto clean metal like the alternator case. If the light lights up then the alternator is faulty (probably worn brushes). If no then the warning lamp bulb has blown or you have a wiring/connection problem between the ignition switch, warning lamp, and D+ terminal.

 

Let us know how you get on.

Hi Tony,

These are my findings:

- When measuring the engine battery it reads 12.57, which makes sense as I have used it last Sunday so it has rained a little.

- measuring between B+ and B- (the case), I get the same voltage of 12.57.

- measuring between B+ and battery neg I get again 12.57

- between B- and battery plus I get again 12.57

So I guess we can conclude that these connections are fine.

 

The thin wire seems indeed to go into the switchboard. There are so many writers that I found it hard to locate it.

 

Unfortunately the charge warning light does not light up with the ignition on (I moved the key halfway and also started the engine but nothing happened.

When pushing the D+ against the case still nothing happens.

 

I realised while doing this that an electrician told me that the engine electrics are connected to the domestics, which might explain why they don't light up as they would take energy from the domestic bank, which is empty. I don't know if I understood this correctly. I have also installed a new leisure battery (and taken it out again) just to test if that would make any difference but in fact nothing happened (I tested the lighting in the boat but that didn't work so I guess there is another problem with the domestics).

 

I hope you can make any conclusions from this and look forward to hear your verdict.

 

Thank you for your guidance.

[Alan de Enfield]

10 minutes ago, Erik.narrowboat said:

 ...hope you can make any conclusions from this and look forward to hear your verdict.

Whereabouts in the world are you ?

 

There may be some one close by who has a bit of electrical knowledge who could do some fault finding for you.

 

You obviously have a multi-meter - do you have an ammeter (ideally a clamp meter) that you can just put around the alternator cable and it will show if there is any current flowing.