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MG Midget and Sprite Technical - electrc trouble

Hello,
My midget does not start.
So I have changed the fuses and charged the battery.
But no more result.
When I want to start, the red lamp does not light on.
One time, the lamp lighted on and when I tried to start, I only had a Clic as noise and nothing else.
Any idea where I have to investigate first?
Thanks
laurent
ld derancourt

Bonjour Laurent,
To begin with make sure the battery IS fully charged and in good condition (try a different one perhaps)and make sure the connections on the battery are clean and tight, and any wires or cables connected to the car body (earths) are also clean and tight.
The "click" is usually caused by the starter solenoid operating but there is not enough power in the battery, (or there are bad connections), to turn the starter motor over as well.
JB Anderson

Is 12,46V enough for the battery?

I turn a second time the key and the lamp lighted on. I tried to start, I heard a clic and the lamp lighed off.

The tension at the solenoid then was 4,26V.
I took the tension at the battery to check the very low tenion and 12,46V and then I heard the electric pump. So I took tension at the solenoid: 12,44V.
And the lamp lighted on.

Could it be the battery?

laurent
ld derancourt

Hi,


Sounds like a classic case of a flat battery to me. Try jumping it off another vehicle laurent. Engine earth lead may be worth checking as well.


Regards Steve.
SR Smith 1

It sounds a lot like a poor connection at the battery.
Dave O'Neill 2

Laurent hi

I think it will be your battery failing

One of its cells may be failing to pass current under load even if it shows enough voltage on no-load testing

You should try to measure the voltage across the battery when you crank the engine over, glamourous assistant could be useful in this test, turning the key for you.

It needs to be no lower than 10.5v when the starter is turning, if it is less the battery has failed

There are several ways of testing the battery but this basic method should be enough.

Bill 1

I have checked the starter. It is not engaged.
I have plug directly the battery to the exit of the solenoid and the starter did not have a sign of running. Nothing appears, just sparks at the end of the junction lead.
I tried another time with the key, and I had lot of clics and after that, the red lamp still lights on.
So I think the starter is out of order.
laurent
ld derancourt

Test while you turn the key Laurent

4.26v after an attempt to start it tells me the fault is the battery not the starter.

Try another battery or jumpleads from another car just while you test it
Bill 1

It sounds to me like the starter is jammed in contact with the flywheel, but you say the starter is "not engaged" so it can't be that.

Must just be the starter motor itself is faulty and is causing such a heavy current drain that the lights go out when you try to engage it.

If the starter IS jammed then try rocking the car back and forward in gear to turn the engine and flywheel slightly to free the starter pinion.
JB Anderson

I have change the starter and sill the same problem. So I will try to jumplead from nother car or buy a new battery to investigate this way.
ld derancourt

Just to give you a feed back.
The battery falls from 12,51 to a dramatical 1,93V when I turn the key.
Sounds the battery is out of order.
laurent
ld derancourt

yes it does

losing such a massive amount of battery voltage indicates a "on-load breakdown" between the cell connectors usually Laurent

When there is no load it will pass a light current but when you add the starter load the faulty connection can fail

may I suggest you do not attempt to start it in this condition too often

If the connection fails and sparks you could get an exploding battery if it allows a spark inside a hydrogen rich cell "atmosphere"


Please take care
Bill 1

This thread was discussed between 28/05/2011 and 29/05/2011

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