Can I start ignition whilst charging starter battery?

[hackenbush]

Jump starting a car would involve turning the ignition during the charging process, is it the same for a boat?

 

The reason I ask is that my starter battery is flat. I've been charging using a genny on the towpath but all I could get out of it was a weak cough.

 

Possibly related - is the bilge pump usually powered by the starter motor?

[nbfiresprite]

The pump is normaly powered by the starter battery. The ignition does need to be turned on when jump starting.

[OldGoat]

hackenbush, on 19 Nov 2016 - 1:37 PM, said:

Jump starting a car would involve turning the ignition during the charging process, is it the same for a boat?

 

The reason I ask is that my starter battery is flat. I've been charging using a genny on the towpath but all I could get out of it was a weak cough.

 

Possibly related - is the bilge pump usually powered by the starter motor?

1. Jump start - yes it is the same

2. The 12V from the genny is not suitable / will not work to charge the battery. It's a fixed voltage designed to power a lamp - or something similar.

3. I don't quite understand - but I'm guessing the bilge pump gets its power from the starter battery - which is not a good thing. Do you mention that because you think the pump has been running when unattended and hence the battery is flat.

 

You need a battery charger (one of the inexpensive C-Tek types would do) and run it from the generator to be of any use.

 

Looking at the previous post which appeared while writing this. I would disagree - mebe OK ('ish) to run the bilge pump from the starter battery but ONLY

if its used while the engine is running / controlled by an on-off switch.

[hackenbush]

Yes, I should have said I'm using a Ring battery charger connected to genny.

 

And yes, I noticed the pump wasn't de-bilging and removed some gunk and it started working again. Since then my battery went flat.

 

Any tips on jump starting or is it just a case of charge for an hour and turn ignition?

[hackenbush]

ignition?

Edited November 19, 2016 by hackenbush

[Arthur Brown]

Do you have a charged house battery? Is it the same voltage as the starter? Can you jump start the engine from the house battery?

[hackenbush]

Do you have a charged house battery? Is it the same voltage as the starter? Can you jump start the engine from the house battery?

That is exactly what I'm doing now. I've swapped over the batteries and since the genny is on I'm giving the house battery some extra juice and then I'll see

[Murflynn]

 

3. I don't quite understand - but I'm guessing the bilge pump gets its power from the starter battery - which is not a good thing.

strongly disagree.

 

it is common to power the bilge pump from the starter battery, for the simple reason that the leisure batteries may be run down by fridge and other continuous loads, but the starter battery should always be fresh and fully charged.

 

.... and the most important load is the automatic bilge pump; it should not be isolated by the main battery isolation switch - it is an essential 24/7 load.

[hackenbush]

Do you have a charged house battery? Is it the same voltage as the starter? Can you jump start the engine from the house battery?

Swapped the batteries, charged for over an hour. No luck. Budget is a problem. I can either buy a gizmo to check the state of the batteries or a new battery but not both

strongly disagree.

 

it is common to power the bilge pump from the starter battery, for the simple reason that the leisure batteries may be run down by fridge and other continuous loads, but the starter battery should always be fresh and fully charged.

 

.... and the most important load is the automatic bilge pump; it should not be isolated by the main battery isolation switch - it is an essential 24/7 load.

I do get that logic, except the bilge pump is almost certainly the reason the starter is flat and therefore my bilge pump isn't working either!

[Drayke]

For jump starting no need to swop batteries over, just use a jump lead between the positive terminals of house battery to engine start battery.

[hackenbush]

For jump starting no need to swop batteries over, just use a jump lead between the positive terminals of house battery to engine start battery.

Ok, I can swap them over tomorrow and try and jump start. Could you explain exactly what I do or is that exactly it - leave neg cables attached on both batteries and connect them with a positive jump lead?

[Drayke]

Ok, I can swap them over tomorrow and try and jump start. Could you explain exactly what I do or is that exactly it - leave neg cables attached on both batteries and connect them with a positive jump lead?

Correct.Just connect jump lead between positive terminals.

Don’t forget to check that all your terminals including the battery isolator switch are clean.

[Murflynn]

Swapped the batteries, charged for over an hour. No luck. Budget is a problem. I can either buy a gizmo to check the state of the batteries or a new battery but not both

 

I do get that logic, except the bilge pump is almost certainly the reason the starter is flat and therefore my bilge pump isn't working either!

if your bilge pump has flattened the starter battery then you (or an appointed watcher) should have been alerted and done something about the underlying problem.

 

if what you say is correct, the bilge pump would flatten any battery in the course of time.

[hackenbush]

Correct.Just connect jump lead between positive terminals.

Dont forget to check that all your terminals including the battery isolator switch are clean.

Will do.

And for extra clarification - I disconnect positives on both batteries and connect positive jump lead between them?

if your bilge pump has flattened the starter battery then you (or an appointed watcher) should have been alerted and done something about the underlying problem.

 

if what you say is correct, the bilge pump would flatten any battery in the course of time.

I believe this is it anyway. I cleared the pump of crud which got it going again but should have made sure I ran the engine after

[hackenbush]

Correct.Just connect jump lead between positive terminals.

Don’t forget to check that all your terminals including the battery isolator switch are clean.

Also, should I swap them back round or leave them as is? - starter battery is now inside and leisure battery out

[WotEver]

And for extra clarification - I disconnect positives on both batteries and connect positive jump lead between them

No. you don't disconnect anything. You simply link both positives with a jump lead.

 

However, if both batteries are flat then you're on a hiding to nothing.

[MtB]

No. you don't disconnect anything. You simply link both positives with a jump lead.

 

However, if both batteries are flat then you're on a hiding to nothing.

 

 

Not necessarily. One heavily discharged engine batt might not turn the engine over but jump a bank of four flat domestics to it and all five might manage to spin it up enough to start.

(Guess how I know this!)

[Murflynn]

 

I believe this is it anyway. I cleared the pump of crud which got it going again but should have made sure I ran the engine after

err ...................... are you saying that the pump was blocked and not passing any water? otherwise the main issue is that your boat is taking on water and may sink - that needs to be fixed as a priority.

 

if the bilge pump consumes say 1kWh of power and this flattens a battery then it must have been running for possibly 15 hours. that is a lot of water.

[WotEver]

Might not be a lot of water - might be crud preventing the pump from removing a little bit of water for hours and hours and hours...

[hackenbush]

err ...................... are you saying that the pump was blocked and not passing any water? otherwise the main issue is that your boat is taking on water and may sink - that needs to be fixed as a priority.

 

if the bilge pump consumes say 1kWh of power and this flattens a battery then it must have been running for possibly 15 hours. that is a lot of water.

 

 

Might not be a lot of water - might be crud preventing the pump from removing a little bit of water for hours and hours and hours...

Yes, I had been checking water level and although not enough to sink the boat it was getting higher enough to worry, totally submerging the pump.

 

I had to buy a new starter battery and got the engine going but the bilge pump isn't working again. This time there's no crud in it to stop it working. I'm fearful of two things: 1) the pump starts working when I'm not there and runs the battery flat again and 2) the pump doesn't work and water fills the hull!

[WotEver]

2) try to fix the leak?

 

1) if it's not working then disconnect it.

[Murflynn]

do you know if is it rainwater or a hull/sterngear leak?

 

most times something isn't working at 12v it is just a poor connection.

Edited November 20, 2016 by Murflynn

[hackenbush]

2) try to fix the leak?

 

1) if it's not working then disconnect it.

 

 

do you know if is it rainwater or a hull/sterngear leak?

 

most times something isn't working at 12v it is just a poor connection.

The leak is sterngear. it's an insignificant but steady drip (which becomes significant because of time). I was told a drip from the sterngear is expected. I tighten it after every journey and recently when stationary. Was this good advice?

[Jak]

A small 'Leak' from here is normal afaik. It's certainly my been experience despite regularly doing the greaser. But this is a tiny amount of water and why we have bilge pumps. How long are you leaving the boat unattended?

[WotEver]

A drop every few minutes is normal. A steady drip suggests the packing is worn out or it's poorly adjusted.