MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG Midget and Sprite Technical - Ignition problem

I have a 76 midget, which i'm restoring. The car has been stood for approx 8 years. Trying to start but I am not getting a spark from the coil, the coil is new, as is the points, dizzy cap,battery,ht leads and coil.Any help would be appreciated please!!.
G Rawson

Are you sure that you have the insulation washers for the points spring in the correct positions so that the spring and connecting wire is properly isolated from the dizzy base plate?
Guy Weller

A silly suggestion perhaps, but a valid one - have you changed the condenser? Some of us have been immobilised by dead condensers, and have tried everything first before discovering that.

Best of luck,

-:G:-
Gryf Ketcherside

Guy, thnks for the info, I will check, but pretty certain it's Ok, but I'm thinking I've got a grounding prob on the dizzy
Gryf
Thanks,yes I have replaced the condenser, forgot to put it on the list of things I've renewed.

Grahame
G Rawson

Graeme, with the ignition on do you have voltage at both sides of the coil LT connections if you disconnect the white/black wire at the distributor?
should be!

Next do you have 12v at the disconnected end of the white/black wire to the distributor, before you reconnect it?
should be!

When you reconnect it is there a faint spark (best done when there's little background noise, those little clicks help diagnostics along nicely)
tells you if you have an earth path through the points which you should only have if the points are closed!

If the points are open is there 12v at the point where the wire joins the points? if not you have a short which will stop your coil making a spark.

if the voltage stays when the points close tells you there isnt a circuit when there should be, possible distributor earth wire broken at the distributor base plate

if all is well then check for the HT side of the sparks, bad HT leads, open circuits or shorts to earth possibly a bad rotor arm losing the spark to the spindle

keep us advised
Bill sdgpm

Grahame,
I wasn't meaning to "teach the sucking of eggs" but it is so easy to get those little washers in the wrong order and result in earthing of the points. It does seem to me that whenever someone says they have fitted new points and subsequently gets no spark it is very often the cause of the problem.
Guy Weller

Thanks bill I'll run those checks tomorrow after work and will keep you posted.

Guy
Sorry if my earlier reply seemed offhand, it wasn't meant to be, I will check and let you know.

Many thanks to both of you for your input, it's much appreciated. This is my 1st restoration project so I'll probably be spending as much time on this site as I will in the garage!!.
G Rawson

I didn't think your response offhand, Grahame. But I did think my original comment was maybe a bit cheeky!
Guy Weller

Try our website for a step by step procedure on solving ignition problems. Also demonstrates how to use and interpret a multimeter.

http://www.mgcars.org.uk/mgcc/midgetreg/workshop.shtml

I also feel that Guy has the right answer however, a very common fault/error.

If it is a condenser then you can hit me across the face with a wet fish. LOL
Robert (Bob) Midget Turbo

Guy,Bob.
You've really got me thinking now. Basically I replaced the points, taking note of how it was originally fitted, so if that was wrong, then I've fitted in wrong, can you explain exactly where the washers go please. Also I have had a look at the earth lead and it doesn't look in too good condition. Do I have to replace as per the original or is it OK to make one up? Thanks for your help guys, I really appreciate it
Grahame.
G Rawson

Plastic washer with the sleeve upwards on the points pillar; then the points spring; then condenser and coil wire; now plastic washer with sleeve turned downwards; finally, the nut.

The idea is to electrically separate the condenser/coil wire/points spring from the points pillar which is firmly connected to earth. (The intermittant connection to gound is then through the points opening and closing...)

A
Anthony Cutler

Thanks Anthony
Grahame
G Rawson

Thanks for everyone's input, it was the washers sited wrong, the car now starts, what a fantastic momemt, to bring an engine back to life after 8 years lying dormant is an awesome feeling.
G Rawson

good news Graeme

well done, now get about and enjoy it
Bill sdgpm

Grahame,
Good news. Glad you got it fixed.

Guy
Guy Weller

Glad it was NOT the condensor (As if?)
Wet fish can be stood down, thank you!
Robert (Bob) Midget Turbo

This thread was discussed between 05/05/2009 and 06/05/2009

MG Midget and Sprite Technical index

This thread is from the archive. The Live MG Midget and Sprite Technical BBS is active now.