2cv with no power to dash instruments and no spark at plugs

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chudski
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Joined: 23 Jan 2024, 17:36

2cv with no power to dash instruments and no spark at plugs

Post by chudski »

Hi, 1st time posting. So as described. guessing the coil is done. Was sold the wrong spark plugs and was unaware (Bosch WR7BC), wouldnt mind but a french garage sold us them! so fitted the new ones today (NGK B7HS)

Am thinking the bosch plugs have knackered something up as the car started misfiring and popping. Tried to start the car today and found she wouldnt start, no spark at plugs also there is no dash lights or power to dials (petrol and battery)

She cranks no bother. Have cleaned the ground terminal on the bulkhead hoping it was a bad ground but no luck. Fuses are all good. She got a new carb a few months back and ran spot on.

Inlet manifold is leaking petrol so that needs fixed. Anything down in the guts that needs checked when the engines in bits.

any help is appreciated.

Thanks

Chud and Carol
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Michel
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Re: 2cv with no power to dash instruments and no spark at plugs

Post by Michel »

Have you got power on the low tension side at the coil?
chudski
Posts: 3
Joined: 23 Jan 2024, 17:36

Re: 2cv with no power to dash instruments and no spark at plugs

Post by chudski »

Hey. Yeah got 12v to the coil. So guessing the coil is pooped...it does look old tbh. I see theres a NGK coil available and looking at that 123 electronic points thing. Any others that are better than original

Any idea on the no power to dash?
RichardW
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Re: 2cv with no power to dash instruments and no spark at plugs

Post by RichardW »

I've moved this into Citroen.

Is it still running points? You can check the coil with a multimeter for resistance, and you should be able to make it spark by grounding the -ve terminal, and then letting it off. I'd have thought points and / or the ballast resistor are more likely causes of fail to spark than the coil.

Power to the dash you will need to work back to find out where the power stops. Have you put a test light on the supply to the coil - it may show 12V on a meter, but it may not be able to carry any current!
Richard W
chudski
Posts: 3
Joined: 23 Jan 2024, 17:36

Re: 2cv with no power to dash instruments and no spark at plugs

Post by chudski »

Hey. Yes still have points. Dunno whats i did but she started up 1st turn. was done for the day and just tried to see if anything changed... YAY. Power back to dash and oil pressure light works again as does the petrol guage. Turns out there is a pair of brown wires going through where the speedo cable goes through the bulkhead from inside. theyve been "jumped" together but the wire must have had corrosion or bad contact. Tomorrow im going to join the wires properly



Thanks
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Michel
(Donor 2022)
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Joined: 29 May 2017, 13:50
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Re: 2cv with no power to dash instruments and no spark at plugs

Post by Michel »

I've had 5 2CVs. That wiring looks quite normal for a 2CV 🤣

I've never bothered with a 123 unit, points and a decent coil for me. Plenty love the 123 unit though.