Dynamo question.

[Windy Pig]

Last night, as I was reversing the car in to a tiny space, I stalled the engine (it was very dark, and yeah I'm an idiot), and it wouldn't start again. I got a splutter from the ignition, but nothing else. I assume this is just a dead battery, but I tried cranking it to no avail (although, I've had trouble before on the crank so it might be my fault.)
Anyway, that's fairly irrelevant, what I wanted to ask was how common is this, and do I have a dynamo problem. There is a volt meter fitted, and in normal running, with heater, lights and wipers (i do a lot if night driving due to my work) the needle sits happily at around 15, but as soon as I have to stop, it just falls right away, meaning I either sit at the lights with the revs up slightly, or turn off wipers and heater till I get going again. I may have left the reversing light switch on (fitted after market) would that drain the battery significantly if sat for a few hours? Do I need a new battery or will I be able to crank it and get it sorted that way?
Be gentle, I'm fairly good mechanically, but electrically I'm a bit of a dunce.

Thanks.

[tomas.geoghegan]

hi There if it is a charging problem?? Might be your battery?? Is your Dynamo Charging ?
I Have the same problem When i use the lights i always need to charge my battery .Because The Dynamo Is NOT safficient
I don"t mind charging my battery up After using my lights etc Every now and again. And wan"t to keep it ariginal And Cost.!
I would advise fitting an alternator . If Thats your problem.
Hope this Helps Tomas

[Alec]

Hello W.P.,

from what you say your dynamo is charging, if it maintains 15v with lights and wipers on that's good. You don't need to worry about it dropping off when the car's idling, the battery will supply the load for that short while and quickly get recharged once you start driving again.
Yes leaving the reversing light on for a few hours would drain the battery, but it should not need replacing if it normally keeps a charge. Charge it up and try again, I don't think you really have a problem?

Alec

[Windy Pig]

I don't mind charging the battery, but if an alternator is easy to fix in, then I may think about it.
At least what you're saying is that its not uncommon to run the battery down like that.

[Windy Pig]

Thanks Alec,
I'll bang a charger on tonight and see where we go. It looks a fairly old battery, so a replacement may be in order.

[bmcecosse]

Your voltmeter tells you it's charging ok although could be worth checking the fan belt is tight enough. Rev light?? What's the point of that??? And surely it will be wired through either ignition (or lights) - so shouldn't have been on for any length of time. It MUST have a warning light anyway (unless switched automatically). I'm guessing the battery is getting a bit short on capacity - how old is it? But you certainly have the right idea about 'managing' the current when stopped in traffic - the heaviest user of course is the headlights - so make sure they are OFF in town traffic. If you do a 'lot' of night driving - an alternator will probably be the best way forward for you. Meantime - it should start on the handle ok - or a bump start - or jump leads!

[tomas.geoghegan]

Hi There to make shore. Charge your battery up. And Get a drop check on it To make shore its not the battery .
If you Can"t Do it your self Then your local garage will ! Then you will no for shore what line to go down
Best Regards
Tomas

[mike.perry]

I think that next year's Nat. Rally demonstrations should include "How to crank start a Minor engine"

[Windy Pig]

Just a switch on the dash, there is a fog light switch next to it that doesn't work, and to be fair, I have never bothered to check why.
I'll have a goose at whether the reversing light is hooked in to the ignition, but by the state of some of the things that have been added to the car I've come across so far, nothing would surprise me.

How difficult is it to swap out a dynamo for an alternator?

[tomas.geoghegan]

Just a switch on the dash, there is a fog light switch next to it that doesn't work, and to be fair, I have never bothered to check why.
I'll have a goose at whether the reversing light is hooked in to the ignition, but by the state of some of the things that have been added to the car I've come across so far, nothing would surprise me.

How difficult is it to swap out a dynamo for an alternator?

Check your Battery First
Tomas

[Windy Pig]

Definitely will check the battery Tomas, but as I'm going to be driving to and from work in the dark for the next month or so at least, and possibly longer, I'm thinking alternator might be the way to go anyway.

[tomas.geoghegan]

Great! Alternator kits are around £70 £80. Try Bull motif or ESM Minors
Tomas

[tomas.geoghegan]

Hi Alternators are not hard to fit Personaly as im not very good at electrics would get a garage to do it.
Or evan better do you have some one you no that can do it. (beware of some Garages)
Tomas

[Windy Pig]

Electrics are not my strong suit I'llbe honest, but I am keen to learn this stuff. The lady wifes dad used to work as an engineer in Formula one, and is willing to help when I get stuck. Was a god send when it came to getting the most out of a 948 minor.

[tomas.geoghegan]

Electrics are not my strong suit I'llbe honest, but I am keen to learn this stuff. The lady wifes dad used to work as an engineer in Formula one, and is willing to help when I get stuck. Was a god send when it came to getting the most out of a 948 minor.

A rocket propelled Morris Minor in the future then LoL
Im a sprayer and panel beater by trade And machanics are no problem.
Tomas

[bmcecosse]

Alternator is simple to do - scrap yard raid to get one from a Mini or Metro etc. F 1 Dad will be able to fit it inside 5 seconds...... But at the moment - that's not the problem. The dynamo IS charging.

[Windy Pig]

True, I'll charge the thing up, disconnect the reversing light, see where we end up. Is there a possibility of the dynamo working but the charge not reaching the battery? Or is it be dead?

[JOWETTJAVELIN]

There's absolutely no need to fit an alternator unless you are doing a lot of short runs with wipers, heaters and lights on or have a big sub in the boot.

Your charging system sounds fine to me: at idle the charge warning lamp will come on because the engine isn't turning fast enough for the dynamo to cut in.

As long as it goes off when you are moving along it is fine.

[JOWETTJAVELIN]

I should also add the following, considering your battery is getting on. Have you checked to see if the cells need topping up?

[Windy Pig]

NO, I will check that.
Well, I just jumped in her, to try another crank start, firstly my earlier information was wrong, about 13 on the volt meter in normal running, not 15. But she started. No crank. Thought I'd try her, and with a cough, she came to life. What does tthat indicate?