Battery voltage - Engine Battery

[Bigplumbs]

This is an observation from a scooter but could equally be a boat.

Many Battery nerds will tell you that once a normal lead acid battery drops below about 11.8 volts it is a dead gonna.

Well I am on a 200 cc hired scooter in Greece at the moment and needless to say they are not all maintained to how they could be.

The screen says the battery voltage is 11.2 volts but it starts the scooter (electric start ) just fine. All systems work well and the lights are very powerful.

Last night at switch on with the lights on and prior to starting it dropped to 8.6 volts. When running it is charging at 13 plus volts.

Now all this tells me that the battery nerds have got it wrong in certain cases.

And no I would not have a battery in this state on my boat but on this scooter it is fine

 

[Keith-i]

Have you considered that perhaps the battery is fine and the meter is out? Or maybe a poor connection causing a low reading. Did you not have your battery tester with you.

 

[Binnacle]

Plumbs, you are, not for the first time, jumping to misleading conclusions that you have chosen to fit your own limited scientific knowledge and experience. The forum battery experience far exceeds your own.

 

[Portofino]

Plumbs, you are, not for the first time, jumping to misleading conclusions that you have chosen to fit your own limited scientific knowledge and experience. The forum battery experience far exceeds your own.

Yep ^

A 2 T scooter will have a stator which provides spark via a coil .All it has to do spin a bit
You can spin it with it your leg AKA kick starting .Or indeed bump it doesn’t need a bat to fire up .
A tiny electric motor AKA as “ electric start “ only had to substitute your leg ….ie spin the stator .It’s not providing spark as such .

If it’s well tuned ( contrary to the OPs opinion) it will fire up within 1/2 or a full kick or almost immediately if electric start .

Where as with a boat with big diesels the 18-1 compression the these day modern electrotwackery ( ECU s injectors , common rail pumps and everything to link them up - etc etc ) 11.7 V will struggle and it’s risky going to sea anchoring up over night and expecting no hassle re starting .

Same in the car world ^ these days , if you like Christmas lights and wish to see them on your dash cluster go ahead run around under 11.7 V

 

[Refueler]

"Portofino" - Think you'll find that most scooters etc will have small CDi units now ... with the old 'stators' if still fitted instead of a small alternator - to charging the small battery / lights etc.

 

[paradave]

This is an observation from a scooter but could equally be a boat.

And no I would not have a battery in this state on my boat

So does it apply to boats or not? Your post makes your own view ambiguous.

The other view to yours, and by that I mean everyone else in the world, is that you’re wrong and this is isn’t applicable to boats.

Even my motorbike won’t turnover with a voltage less than 11.7.

 

[Portofino]

"Portofino" - Think you'll find that most scooters etc will have small CDi units now ... with the old 'stators' if still fitted instead of a small alternator - to charging the small battery / lights etc.

My “ coil “ your CDI is the same thing , just different description.
Some folks still call them coils . Are we both talking about the unit connected to the frame that had a plug lead to the cylinder.

This red thing

Guess it the same SMALL with OB s you don’t need a battery . You spin it ( stator ) with the pull cord .

 

[ylop]

When running it is charging at 13 plus volts.

It it charging or it the system voltage just >13V. The number when the engine is running just tells you the alternator is working, it doesn't actually mean any charge is being successfully stored. If it was charging, then after using it and allowing it to "rest" the voltage would would be higher than before.

 

[PaulRainbow]

Plumbs, you are, not for the first time, jumping to misleading conclusions that you have chosen to fit your own limited scientific knowledge and experience. The forum battery experience far exceeds your own.

I have some potatoes in the locker with more battery knowledge than Plumbs

 

[Bigplumbs]

Yep ^

A 2 T scooter will have a stator which provides spark via a coil .All it has to do spin a bit
You can spin it with it your leg AKA kick starting .Or indeed bump it doesn’t need a bat to fire up .
A tiny electric motor AKA as “ electric start “ only had to substitute your leg ….ie spin the stator .It’s not providing spark as such .

If it’s well tuned ( contrary to the OPs opinion) it will fire up within 1/2 or a full kick or almost immediately if electric start .

Where as with a boat with big diesels the 18-1 compression the these day modern electrotwackery ( ECU s injectors , common rail pumps and everything to link them up - etc etc ) 11.7 V will struggle and it’s risky going to sea anchoring up over night and expecting no hassle re starting .

Same in the car world ^ these days , if you like Christmas lights and wish to see them on your dash cluster go ahead run around under 11.7 V

It’s a 4 stroke. I fear you might be a little behind the times re scooters

 

[Bigplumbs]

I have some potatoes in the locker with more battery knowledge than Plumbs

Your Potatoes must have got a first from Cambridge cos I only got a 2/1.

As I said it works fine so that is real life proof. So many theory monkeys won’t accept real life results. Which if you were able to work it out was the point of this thread.

Wot do ya no abot Batrys then Pauly boy

 

[Bigplumbs]

It’s a 4 stroke.

My “ coil “ your CDI is the same thing , just different description.
Some folks still call them coils . Are we both talking about the unit connected to the frame that had a plug lead to the cylinder.
View attachment 178769
This red thing

Guess it the same SMALL with OB s you don’t need a battery . You spin it ( stator ) with the pull cord .

Hey Porto learn how to resize you pics

 

[Bigplumbs]

I have some potatoes in the locker with more battery knowledge than Plumbs

I see you are from Suffolk. I will keep an eye out for you. Would be fun to have a chat

 

[PaulRainbow]

I see you are from Suffolk. I will keep an eye out for you. Would be fun to have a chat

From Suffolk at the moment, in the Haven at Ipswich.