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MG Midget and Sprite Technical - 1500 starting issues

I have been having issues with starting my 1500 midget after it has been left standing for a few days. Today i thought i would do some exploritory work on it to see if i can identify the fault but i think i have blown the electronic ignition unit.
I need to know and dont seem to be able to find out if the 1500 has a ballast resited ignition circuit. I was looking at buying an accuspark distributor and coil. This requires a 12volt supply and not a ballast resisted supply.
How do i find out what sort of circuit is fitted ?
Thanks in anticipation.
S Langston

Check the Accuspark website. They describe how to test if you have a ballast or not. ( http://www.mgbreakers.com/accuspark/faqs.html#q2 ) The 1500 should have a ballast resistor built into the loom (basically it is a long resistor wire within the loom so it is not a discrete component that you can see).

What you do is that you connect your negative side of the coil (the side that goes to the distributor) to ground. Then you turn on the ignition and measure the voltage over the coil, that is the voltage between plus and minus terminals on the coil.

If you have a ballast then the 12 V from the ignition will be divided with part of the voltage over the resistor and part over the coil ( typically 6-9 volts over the coil). If the voltage over the coil is about 12 V then you do not have a ballast.

I ordered the Accuspark kit for the 1500 without checking first.... I checked just before fitting it and it seems some PO bypassed the ballast so I had to get a 12 V coil (non ballast coil). Bugger.... You live and learn. :)

With that sorted the installation was easy and it works perfectly.

//Erik
E Lindgren

The Accuspark will work both on ballast (6 V coil) and non-ballast (12 V coil) systems.

//Erik
E Lindgren

Sorry, this page is the one you want http://www.mgbreakers.com/accuspark/fitting_guide.html

//Erik
E Lindgren

As said accuspack will work with both but if you're changing the coil you will need to know which type you have. Voltage measurement is the way to go as it will confirm if a PO has made any mod's. If a meter is not available an easy check is to see if the +ve terminal has two wires attached to it.. One from the ballast wire and the other directly from the starter switch crank position which bypasses the ballast during starting. If memory serves me correctly the wire colour is green with a white tracer line.

MGmike
M McAndrew

>>> If memory serves me correctly the wire colour is green with a white tracer line. <<<

On my '78 those two wires are white with a light green tracer.

-:G:-
Gryf Ketcherside

Gryf, memory is not what it once was!!!!! Important thing is two wires and not one on a 12v coil, thanks for the correction.

MGmike
M McAndrew

I have fitted a new accuspark 12v coil with a new accuspark distributor with points fitted today. The Midget started second turn of the key. Excellent !
Just going to fit a new electronic fuel pump when the postie delivers it and all my tinkering is done for the time being.
Had a ride out in it this afternoon, roof down. It was raining but did i care ? NO !! Grin factor 10*
S Langston

This thread was discussed between 26/10/2011 and 29/10/2011

MG Midget and Sprite Technical index

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