Simple question batteries

[Northernlass]

On the ignition key there are 3 positions to turn it to aux, heat, start, and just run I think, the letters on the positions have long since faded and I can hardly tell what letter they say, but my question is should I keep the key turned to aux to charge the leisure batteries while running the engine, sorry if this seems a daft question I haven't got a clue

[Paul C]

You said there's 3 positions but then mentioned 4 positions! Firstly can you clarify it has 4: off, heat, on, start. If its anything like a normal ignition switch it should spring back from the start position to the on position.

 

Secondly, nobody can say for sure how your boat has been wired or configured. BUT in normal circumstances, the engine running in the normal on position is the position the switch should be in. How do you stop the engine? Stop button? Does this work in any position, or just with the ignition on? Does an alternator light illuminate or a buzzer sound if the ignition's put to the off position while the engine running?

 

Also, how many alternators does the engine have, many boats have one alternator + a split charge relay, but newer boats often have 2 alternators, one for each battery bank.

[bottle]

Procedure:

 

Turn key to heat and hold (depending engine type/make it varies between 10 and 30 seconds),

 

Turn key to start,

 

When engine starts release key and it will 'spring' back to the run position and that is where it should be whenever the engine is running.

 

To stop engine push stop button or pull engine stop cable, again depends on engine.

 

When engine stops return key to OFF and remove.

[Naughty Cal]

Procedure:

 

Turn key to heat and hold (depending engine type/make it varies between 10 and 30 seconds),

 

Turn key to start,

 

When engine starts release key and it will 'spring' back to the run position and that is where it should be whenever the engine is running.

 

To stop engine push stop button or pull engine stop cable, again depends on engine.

 

When engine stops return key to OFF and remove.

That sounds like a complicated launch system.

 

I much prefer just turning the key

[bottle]

but you have a car system, that does it all automatically for those that cannot cope with a little complication.

[Naughty Cal]

but you have a car system, that does it all automatically for those that cannot cope with a little complication.

Can you imagine trying to figure out your launch system after a few G&T's .........

[Neil Smith]

What is the engine and has it got a name on the panel as this could tell us more.

 

Neil.

[mrsmelly]

Procedure:

 

Turn key to heat and hold (depending engine type/make it varies between 10 and 30 seconds),

 

Turn key to start,

 

When engine starts release key and it will 'spring' back to the run position and that is where it should be whenever the engine is running.

 

To stop engine push stop button or pull engine stop cable, again depends on engine.

 

When engine stops return key to OFF and remove.

 

I would just like to add a little to this exellent communication in that when the engine has fired when you let key spring back to run position just ensure if it is a little worn that it doesnt spring back a little too far as if it is not in the correct position the engine will still run but you may well not be charging your batteries.

 

Tim

[Northernlass]

Thanks people for the replies

The key stays in any position I have turned it to it does not spring back although when the engine fires up I turn it back to run, the engine is stopped by pulling out the stop button,

It's difficult to explain without seeing I'm sorry if sounds vague,

What does the aux position do ? Apologies

The engine is a thorneycroft diesel inside semi trad stern,

[Northernlass]

Ok well I just looked the key has on ignition

Off

Aux

Heat

Heat and start

It helps if I do put my glasses on lol

So running in aux at moment, it lets me rev the engine and shows on an amp meter / it goes from 50 - to 50 + and the needle stays in the middle lol

Tick over is running at 5 rpm it goes up to 40 on the dial and there's another dial that has volts on it from 8 to 18 and it's running saying 12 v so this is what's charging ?

[Northernlass]

Yes it's charging, I checked with the 12v lights on , so I must have been running engine in the off position cos last nite I had hardly any 12v power to lights, this morning I started the engine ran in aux and hey presto the lights are bright,

God I'm a nutter

[Paul C]

Thanks for the clarifications, basically your ignition switch is worn so it doesn't hold the positions it needs to, which causes your issue. Now you know the workaround, I'd not worry about it though.

[Bod]

When your engine is running, to charge your batteries, I would expect the amp meter to read towards the +50, starting high, and reducing over time to maybe +2 indicating the batteries are charged.

The volt meter I would expect to read 12-13 volts to start, then as the amp meter decreases, the volts should rise to 14.5-14.8v.

 

Hopefully other will come along and give you ideas, where to get a manual for this engine, which will explain all the key positions, if you don't already have one.

 

Bod

[Northernlass]

Thanks guys nice of you to give advice, it's all been a massive learning curve for me even simple things, but I love it and I'm getting there.

It's an old boat but everything I need is here, no manuals tho lol

Sometimes it's reassurance I need as I get a bit scared when I don't understand things haha

[bottle]

Hi Northernlass

 

Just a little aside information, Thorneycroft were the company that marinised your engine the base engine could be from various makers, yours may actually be a BMC

 

That has no connection with the panel but may be of help in getting spares etc.

[Northernlass]

It is a bmc thanks Bottle

[Northernlass]

How do I put this, dangling down on a short cable in the space between the engine panel and door is a smallish box , it has two lights on it a green one and a red, both light up when turn engine on, there's a small push button on it when I press it the green light goes out, what is it ?

[Rob-M]

Are you able to post a picture, that might help in identifcation.

[bottle]

If possible also try to trace where the cables go.

[David Schweizer]

Does the mysterious box have any wttwring or wording on it, or makers name etc?

 

On the ignition switch issue, It would appear that you have a (very) old vehicle ignition switch, where the "aux" position would be to enable any equipment such as a radio to be used whilst the engine is not running and/or when ignition is not switched on. Unless it has not been wired conventionally, the batteries should not charge when in this position. The normal position for charging would be "run".

[Northernlass]

All 12v equipment runs without the key in the ignition just need to keep the red master key switched on, I usually turn it off when I leave the boat to conserve the batteries,

Very in ( ) lol Mr Schweitzer

[Paul C]

You'd be worried if it didn't run without the engine running! Its running, off the leisure batteries. Its possible that a few items only work with the ignition on - our boat is wired so the horn, headlamps and stop solenoid only work with the ignition key in the run position. Everything else eg all the domestic stuff, other lamps, etc work all the time.

 

It would be interesting to know - does the boat have one or two alternators? ANd if one, how are the batteries interconnected (to enable both to be charged) when the engine is running? Most boats with one alternator will have a split charge relay.