Liverpool Boats - Fridge Circuits

[henhullpilgrim]

Hi

 

My first posting after many months of gleaning much valuable info...

 

Just wondered if any owners of a Liverpool Boat might be able to help with this mystery. Happy to take suggestions from anyone else too as I'm completely stumped with this one.

 

My brother-in-law has a 58' semi-trad Liverpool Boat. He's owned it for two years or so. His starter battery keeps letting him down which is disturbing as he's already replaced it once due to failure of the original. Thank heavens for jump leads.

 

He asked me if I had any thoughts on why the battery is not recharging and so we spent this weekend investigating.

 

I'm confident (after testing) that the alternator (twin alternator Isuzu engine) is operating perfectly well and putting charge back into the starter battery.

 

What worries me is the following:

 

1. The bilge pump was contected directly to the starter battery via its stern on/off switch. No sign of a fuse or an 'always-on bar'. I know that this is not the best setup but surely this wouldn't be likely to cause the flattening of the starter battery would it? He has a rear canopy and the pump rarely kicks in as his bilges are reasonably dry. Any way, I suggested he rewires the pump to his domestics until we can setup an 'always-on' bar.

 

2. Coming off his starter battery isolation switch is a red cable (in addition to the cable leading to his starter motor) that leads to a small fuse box with a 15 amp blade fuse. This fuse box is attached to his wooden battery box.

 

The cable becomes brown at the other side of the fuse box (why the colour switch?) and is routed into the main cabling network, bound (we assume) for the main switch panel that is located mid-ships. It's difficult to be certain without removing internal panels as the cabling enters the boat through a bulkhead between the engine compartment and the bedroom.

 

When the fuse is removed, the fridge stops working. More puzzling, the engine will not fire up either, even though the starter motor cable is still connected. Replace the fuse and both the fridge and engine work again.

 

The fridge is also controlled from the main switch panel and I can't think why you have a 15 amp fuse cable off the starter battery as well as a 15 amp panel switch too!

 

3. Even more intriguing, is the fact that coming directly off the domestic isolator switch is a brown cable that is routed to the same fuse box as above. It carries a 5amp fuse. The cabling leaves this fuse as red cable (why the colour switch) and also joins the main cabling network, passing through the bulkhead and presumeably heading for the switch panel. Remove the fuse and everything on the 12 volt system continues to work. The cable to nowhere?

 

Why would you change the cable colours at a fuse box? Is this a secret method of cabling known only to electricians?

 

Why would you have a fuse box in the engine bay (when you've got a switch panel mid-ships) and why would you connect the fridge to the starter battery, using it?

 

Why would disconnecting the fridge imobilise the engine?

 

Have any of you Liverpool Boat folks got the same setup and if so, can you explain?

 

Many thanks in advance.

[Gibbo]

The fridge shouldn't be on the engine start battery and it sounds like it is.

 

I'm wondering if those swapped coloured wires are because someone has simply put them back in the wrong place?

 

Gibbo

[steelaway]

Hi

 

My first posting after many months of gleaning much valuable info...

 

Just wondered if any owners of a Liverpool Boat might be able to help with this mystery. Happy to take suggestions from anyone else too as I'm completely stumped with this one.

 

My brother-in-law has a 58' semi-trad Liverpool Boat. He's owned it for two years or so. His starter battery keeps letting him down which is disturbing as he's already replaced it once due to failure of the original. Thank heavens for jump leads.

 

He asked me if I had any thoughts on why the battery is not recharging and so we spent this weekend investigating.

 

I'm confident (after testing) that the alternator (twin alternator Isuzu engine) is operating perfectly well and putting charge back into the starter battery.

 

What worries me is the following:

 

1. The bilge pump was contected directly to the starter battery via its stern on/off switch. No sign of a fuse or an 'always-on bar'. I know that this is not the best setup but surely this wouldn't be likely to cause the flattening of the starter battery would it? He has a rear canopy and the pump rarely kicks in as his bilges are reasonably dry. Any way, I suggested he rewires the pump to his domestics until we can setup an 'always-on' bar.

 

2. Coming off his starter battery isolation switch is a red cable (in addition to the cable leading to his starter motor) that leads to a small fuse box with a 15 amp blade fuse. This fuse box is attached to his wooden battery box.

 

The cable becomes brown at the other side of the fuse box (why the colour switch?) and is routed into the main cabling network, bound (we assume) for the main switch panel that is located mid-ships. It's difficult to be certain without removing internal panels as the cabling enters the boat through a bulkhead between the engine compartment and the bedroom.

 

When the fuse is removed, the fridge stops working. More puzzling, the engine will not fire up either, even though the starter motor cable is still connected. Replace the fuse and both the fridge and engine work again.

 

The fridge is also controlled from the main switch panel and I can't think why you have a 15 amp fuse cable off the starter battery as well as a 15 amp panel switch too!

 

3. Even more intriguing, is the fact that coming directly off the domestic isolator switch is a brown cable that is routed to the same fuse box as above. It carries a 5amp fuse. The cabling leaves this fuse as red cable (why the colour switch) and also joins the main cabling network, passing through the bulkhead and presumeably heading for the switch panel. Remove the fuse and everything on the 12 volt system continues to work. The cable to nowhere?

 

Why would you change the cable colours at a fuse box? Is this a secret method of cabling known only to electricians?

 

Why would you have a fuse box in the engine bay (when you've got a switch panel mid-ships) and why would you connect the fridge to the starter battery, using it?

 

Why would disconnecting the fridge imobilise the engine?

 

Have any of you Liverpool Boat folks got the same setup and if so, can you explain?

 

Many thanks in advance.

 

 

Hi There

 

Many Liverpool boats where sold as 'sailaways' If this was an owner fit out then the wiring will have been done by some one less than an a proffesional.

There is not a standard system of wiring NB's and the quality/ safety is down to the fitters knowledge and the of degree of adhoc electrical circuits

My advice is to inspect the complete wiring system and understand it yourself, then rewire it - correctly.

The starter battery is almost always only used for engine starting, although wiring the bilge pump to it (with a correct fuse) would not be a problem.

The previuse owner may had a habbit of turning of the battery isolaters when he left the boat, so the wiring to to the live side of the switch was to leave some items (ie bilge pump) live.

 

Alex

[chris w]

1. The bilge pump was contected directly to the starter battery via its stern on/off switch. No sign of a fuse or an 'always-on bar'.

 

If you have the normal Isuzu engine control panel with the bilge pump switch incorporated, there should be a white button next to the bilge pump switch. That is a thermal fuse for the bilge pump. The bilge pump won't affect the status of the starter battery unless the pump is actually running.

 

Chris

[henhullpilgrim]

The fridge shouldn't be on the engine start battery and it sounds like it is.

 

I'm wondering if those swapped coloured wires are because someone has simply put them back in the wrong place?

 

Gibbo

 

Thanks for you thoughts.

 

I agree that the fridge appears to be connected to the starter battery... but why then, does disconnecting it immobilise the engine? I just don't understand that. Perhaps this is a Shoreline/Isuzu hybrid

 

To the best of my knowledge, the coloured wires have never been disconnected from the fuse box. My brother-in-law would not touch them and I don't remember anyone else 'playing about' with the boat electrics since he purchased it.

 

I'm confident that they remain as fiited by Liverpool Boats.

 

Still puzzled.

 

Hi There

 

Many Liverpool boats where sold as 'sailaways' If this was an owner fit out then the wiring will have been done by some one less than an a proffesional.

There is not a standard system of wiring NB's and the quality/ safety is down to the fitters knowledge and the of degree of adhoc electrical circuits

My advice is to inspect the complete wiring system and understand it yourself, then rewire it - correctly.

The starter battery is almost always only used for engine starting, although wiring the bilge pump to it (with a correct fuse) would not be a problem.

The previuse owner may had a habbit of turning of the battery isolaters when he left the boat, so the wiring to to the live side of the switch was to leave some items (ie bilge pump) live.

 

Alex

 

Thanks for your thoughts.

 

The boat was partly fitted out by Liverpool on purchase. This included all electrics and plumbing. The only jobs left for self-fitting were cabinet work.

 

I just don't understand why anyone would wire a fridge to the starter battery or why disconnecting it immobilises the engine.

 

 

 

 

If you have the normal Isuzu engine control panel with the bilge pump switch incorporated, there should be a white button next to the bilge pump switch. That is a thermal fuse for the bilge pump. The bilge pump won't affect the status of the starter battery unless the pump is actually running.

 

Chris

 

Thanks for that info. I honestly can't remember seeing the white (thermal fuse) button. If it is there then that would solve one mystery i.e. the missing bilge fuse.

 

For now, we've connected the bilge pump to the domestic batteries and will add an 'always-on' busbar and fuse in due course.

 

I'm still convinced that the fridge is the drain on the starter battery but disconnecting it means we can't start the engine.

Edited May 6, 2009 by henhullpilgrim

[Mac49]

My guess is your fuse/cable to nowhere powers the horn/tunnel light etc. These are powered off the starter battery on my boat. There's half a dozen pics of my Liverpool boat's engine room on this thread (not fitted out) showing battery box, bilge pump switch etc if they're of any use to help describe anything etc.

Rick

edit: could it be possible the wires were the wrong way round from delivery?

Edited May 6, 2009 by Mac49

[henhullpilgrim]

My guess is your fuse/cable to nowhere powers the horn/tunnel light etc. These are powered off the starter battery on my boat. There's half a dozen pics of my Liverpool boat's engine room on this thread (not fitted out) showing battery box, bilge pump switch etc if they're of any use to help describe anything etc.

Rick

edit: could it be possible the wires were the wrong way round from delivery?

 

We removed the fuse on the cable to nowhere and tried everything powered by 12 volts and they all still worked. That included all the nav lights (which feature on the main switch panel) and the horn.

 

I certainly believe that the wires may have been the wrong way around since delivery but everything aboard has worked. It's just that the fridge appears to be draining the starter battery (that it shouldn't be connected to in the first place) and disconnecting it leaves us mysteriously with no engine start. This is even though the main connection to the starter motor remains in tact.

 

I always tend to gravitate towards common sense and logic to solve things (dangerous strategy somertimes I know) but this setup doesn't make sense and appears to defy logic.

[Smelly]

Well, if there's any 15A wire destined anywhere more than about 6 feet from where it starts I'd suggest a rewire even if it was actually working.

[Mac49]

We removed the fuse on the cable to nowhere and tried everything powered by 12 volts and they all still worked. That included all the nav lights (which feature on the main switch panel) and the horn.

 

I certainly believe that the wires may have been the wrong way around since delivery but everything aboard has worked. It's just that the fridge appears to be draining the starter battery (that it shouldn't be connected to in the first place) and disconnecting it leaves us mysteriously with no engine start. This is even though the main connection to the starter motor remains in tact.

 

I always tend to gravitate towards common sense and logic to solve things (dangerous strategy somertimes I know) but this setup doesn't make sense and appears to defy logic.

 

On well, worth a try. The only other thing I can think of with a separate feed on my boat is the central heating boiler, but that has a bigger fuse than 5A. I suppose everything would work (albeit for a shorter time) connected to the wrong batteries and I would take a problem like your drained starter battery to notice the mistake I suppose, hopefully some with more knowledge than me can figure it out.

Rick

[chris w]

I'm still convinced that the fridge is the drain on the starter battery but disconnecting it means we can't start the engine.

I suspect that they have connected the fridge to the starter solenoid fuse for convenience when the fridge was maybe fitted later. Pulling the fridge fuse out therefore also cuts off the starter solenoid. The solenoid fuse would normally be about 40A, what's the size of the fridge fuse that you have found?

 

Chris

[henhullpilgrim]

On well, worth a try. The only other thing I can think of with a separate feed on my boat is the central heating boiler, but that has a bigger fuse than 5A. I suppose everything would work (albeit for a shorter time) connected to the wrong batteries and I would take a problem like your drained starter battery to notice the mistake I suppose, hopefully some with more knowledge than me can figure it out.

Rick

 

Thanks for your help anyway Rick.

 

I suspect that they have connected the fridge to the starter solenoid fuse for convenience when the fridge was maybe fitted later. Pulling the fridge fuse out therefore also cuts off the starter solenoid. The solenoid fuse would normally be about 40A, what's the size of the fridge fuse that you have found?

 

Chris

 

Thanks for you help Chris.

 

The fuse in question is 15 amps. However, the cable is quite separate from the main supply cable to the starter motor. It's simply 'added' to the starter motor side of the start battery isolation switch and is routed into the main boat via the engine room bulkhead. We assume it goes to the switch panel but cannot be sure without removing internal wall panels. Puzzling.

[granddad]

looks like electrics by committee - dont trust any of it - disconnect all the engine power - then wire it up as its got to be -power the engine - then the alternator to the engine start

ken

[Gibbo]

I wonder if someone has powered the fridge via a relay connected to an iginition feed so it only works when the engine is running? Just a thought. Without actuallty seeing the boat it's all guesswork.

 

Gibbo

[Roger Gunkel]

Hi Henhullpilgrim,

 

Can't offer any advice as to how to cure your problem and the electrical experts have already joined the thread.

 

I may be able to throw some light on where the problem comes from though! My widebeam was bought as a lined sailaway, built by Liverpool Boats and with all electrics and panels fitted by them. Initially, I found that virtually all the cabling from the control panel to fridge point, horn, waterpump etc was wired and labelled incorrectly. Some were even connected to the same terminal of the switches, effectively bypassing them. Furthermore when I came to fit a battery monitoring system, I found even more worrying problems. The 3 domestic batteries were wired with both negative and positive take off cables from one battery, rather than diagonally opposite ends of the bank, charging was also going to the same terminals. Much more serious was that the domestic bank isolator switch was wired into the alternator circuit only, with the live takeoff for the distribution panel being connected directly to the batteries, via a washer soldered to the end of the cable. I discovered that after turning off the isolator switch, then hearing the water pump running after a couple of minutes, when my wife filled the kettle. The washer was too small to connect to the isolator connector, so rather than correct it, somebody decided to bypass the switch!!

 

I also have a friend with an LB wired boat who had similar problems and another on the marina here with apalling wiring from new. I would suggest that the same person probably wired the one you are having problems with, perhaps the plumber

 

Roger

[MtB]

When the fuse is removed, the fridge stops working. More puzzling, the engine will not fire up either, even though the starter motor cable is still connected. Replace the fuse and both the fridge and engine work again.

 

 

When you say the engine will not fire up I take it you mean the starter motor turns it over ok but the engine fails to actually start?

 

I'm not a diesel expert but as I understand diesels, once running, the only way to stop a diesel is to remove the fuel supply (as they are compression ignition). An 'engine stop solenoid' is installed for this purpose. It needs to be actuated (powered up) to allow fuel to the injectors. The engine is stopped by removal of power from this solenoid - a fail-safe arrangement. The fuse that powers the fridge probably also powers this solenoid which is why the engine won't fire with it removed. Prove/disprove my theory by starting the engine with the fuse in place then removing the fuse. The engine should stop as though you've turned it off with the ignition key!

 

The stop solenoid fuse takes power from the starter battery so the engine will still run if the domestic batteries are flat. The fridge supply is fitted to the stop solenoid in error in my view, or more likely because someone in the factory just did not care.

 

Someone more expert than me will be along in a sec to say this is all wrong I expect!

 

Cheers, Mike

[RobinJ]

What worries me is the following:

 

The cable becomes brown at the other side of the fuse box (why the colour switch?)

 

When the fuse is removed, the fridge stops working. More puzzling, the engine will not fire up either, even though the starter motor cable is still connected. Replace the fuse and both the fridge and engine work again.

It is common practice for electricians to identify the difference between 'live' and 'switched' or 'fused' wires and the way this is done can vary - change of colour - strip marking - sleeves. I do not think there is any common standard, but generally battery cables tend to be red and black, fused or switched circuits brown and blue, sometimes additional circuits use orange and green, purple and grey etc. In any event this should be documented in circuit diagrams with the boat documentation, a bit like the diagrapms for cars. If the boat was sailaway then this may not have happened, but even proffessional secondary fitters should provide documentation.

 

Commendable that the engine circuits are fused, they aren't always. It sounds like the ignition circuits pass through this fuse and/or the distribution panel, so therefore the starter is live, but the ignition switch is not. At some point (and this will depend on the history of the boat) the fridge has been connected to the same circuit, possibly because it was fitted temporarily before the domestic circuits were installed or added without realising to which circuit it was being connected.

However it depends on what sort of fridge, compressor or convection? A convection firdge should never be wired direct to a starter battery, but only allowed to run when the engine is turning. A compressor fridge should never be connected to the starter battery and always run from the domestic.

[henhullpilgrim]

Hi Henhullpilgrim,

 

Can't offer any advice as to how to cure your problem and the electrical experts have already joined the thread.

 

I may be able to throw some light on where the problem comes from though! My widebeam was bought as a lined sailaway, built by Liverpool Boats and with all electrics and panels fitted by them. Initially, I found that virtually all the cabling from the control panel to fridge point, horn, waterpump etc was wired and labelled incorrectly. Some were even connected to the same terminal of the switches, effectively bypassing them. Furthermore when I came to fit a battery monitoring system, I found even more worrying problems. The 3 domestic batteries were wired with both negative and positive take off cables from one battery, rather than diagonally opposite ends of the bank, charging was also going to the same terminals. Much more serious was that the domestic bank isolator switch was wired into the alternator circuit only, with the live takeoff for the distribution panel being connected directly to the batteries, via a washer soldered to the end of the cable. I discovered that after turning off the isolator switch, then hearing the water pump running after a couple of minutes, when my wife filled the kettle. The washer was too small to connect to the isolator connector, so rather than correct it, somebody decided to bypass the switch!!

 

I also have a friend with an LB wired boat who had similar problems and another on the marina here with apalling wiring from new. I would suggest that the same person probably wired the one you are having problems with, perhaps the plumber

 

Roger

 

Thanks Roger... I suspect that this boat may well have been wired by the same work experience youngster as your boat. I have resisted talking down the build quality so far, just in case there were compelling technical reasons for the way the boat had been wired.

 

However, I'm beginning to gravitate towards the conclusion that poor build quality is the only rational explanation.

 

Arghhhh!

 

But thanks...

 

Brent

 

When you say the engine will not fire up I take it you mean the starter motor turns it over ok but the engine fails to actually start?

 

I'm not a diesel expert but as I understand diesels, once running, the only way to stop a diesel is to remove the fuel supply (as they are compression ignition). An 'engine stop solenoid' is installed for this purpose. It needs to be actuated (powered up) to allow fuel to the injectors. The engine is stopped by removal of power from this solenoid - a fail-safe arrangement. The fuse that powers the fridge probably also powers this solenoid which is why the engine won't fire with it removed. Prove/disprove my theory by starting the engine with the fuse in place then removing the fuse. The engine should stop as though you've turned it off with the ignition key!

 

The stop solenoid fuse takes power from the starter battery so the engine will still run if the domestic batteries are flat. The fridge supply is fitted to the stop solenoid in error in my view, or more likely because someone in the factory just did not care.

 

Someone more expert than me will be along in a sec to say this is all wrong I expect!

 

Cheers, Mike

 

Hi Mike

 

When the fridge is disconnected, the ignition key invokes the usual 'alarm' when turned to the first position. When the key is turned to the 'glow plug' position, the glow plug light does not illuminate and upon turning the key to the starting position, the alarm goes off and the engine fails to turn over. However, there is a clicking noise which appears to be coming from what looks like a relay that feeds the glow plugs.

 

Reconnect the fridge and everything works perfectly.

 

Very puzzling.

 

Regards

 

Brent