No spark

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rreems
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No spark

Post by rreems »

Hi My 68 four door doesn’t have a spark at the plugs!
I have changed the coil still no joy
I did fit an ecuspark unit 2 years ago And has been running fine since my question is could that have failed and how would I check low tension spark?
Thanks
Richard
myoldjalopy
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Re: No spark

Post by myoldjalopy »

Is there a spark at the end of the king lead if you pull it from the dizzy? If so, prime culprits are dizzy cap, rotor, leads or plugs, although it is unlikely all leads and/or all plugs would fail at the same time.
If no spark at the king lead....well, electronic dizzy's can and do fail, so it might be worth fitting the old points set-up if you still have it. There is also a school of thought 'Its never the coil' (unless its a modern one of poor quality) so keep your old one.
rreems
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Re: No spark

Post by rreems »

Excuse my ignorance what is the dizzy? Do you mean the distributor cap? Do I test the main lead by taking not off the distributor cap end and put to earth and turn the car over?
I have replaced the plugs but will put points and condenser in and see what happens! Thanks for the advice
Richard
myoldjalopy
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Re: No spark

Post by myoldjalopy »

Dizzy = distributor. Yes, pull the main king lead from the distributor cap and hold/place it near the engine block, ignition on, and crank - you should see nice fat blue sparks earthing from the end of the lead. Maybe best to hold with insulated pliers in case of shock - if you want to go the whole hog, wear marigolds and stand on a rubber mat!
jagnut66
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Re: No spark

Post by jagnut66 »

Hi,
I have one of these testers (link below), not expensive and very useful.
Best wishes,
Mike.


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1954 Series 2: 4 door: "Sally" -- Back on the ground with (slave) wheels and waiting to be resprayed......
1970 Triumph Herald 1200: "Hetty" -- Driven back from Llangollen in Wales (twice.....)
rreems
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Re: No spark

Post by rreems »

Thanks again, I’ll remember what the Dizzy is next time!!
Thanks Mike I do have one of those plug testers very useful.
Thanks for your help
Much appreciated
Richard
rreems
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Re: No spark

Post by rreems »

Hi I Left the Ecuspark unit in, tried taking the main HT. lead Out of the dizzy putting to earth turning the car over no spark! Tried a new coil Repeated the process no Spark!

I have new points and condenser to try but don’t know how to wire up as the wires for the Ecuspark are attached to the unit
I have taken a photo of points and condenser see link below and wondered If someone could help
Many thanks
Richard
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geoberni
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Re: No spark

Post by geoberni »

Have you checked to see if you've got the LT (12v) side of the coil circuit correct?
All the talk has been about the HT side so far.

Is there 12v to the coil when the ignition is switched on?

The Ecuspark/Points switch the earth on and off. see here:

https://www.minimania.com/images/LucasP ... _img_0.gif

Edit to add:
LT is Low Tension i.e. the 12v side of the system, HT is High Tension, the 10000's of volts that are generated by the coil to give you the spark. :wink:
Last edited by geoberni on Tue Jun 30, 2020 9:22 am, edited 1 time in total.
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mogbob
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Re: No spark

Post by mogbob »

Richard
This link to a YouTube video will "paint a picture " for you on a conventional set up : -
https://www.youtube.com/watch?v=T01lZdAsP9I
" Ecuspark "...I've not come across that particular Electronic Ignition set up before. Could it possibly be
Accuspark ? In which case there fitting instructions on their website http://www.accuspark.co.uk/fitting_guid ... %20More%20

Bob
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Re: No spark

Post by rreems »

Hi Bob you are correct it is Accuspark my mistake! I was going to try points again to see if the unit was duff it’s only been fitted for 3 years, but I don’t know how to wire up with A points set up! Electrics isn’t a strong point so not sure where the Wires attach from the dizzy to the coil!
Thanks
Richard
myoldjalopy
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Re: No spark

Post by myoldjalopy »

Here is a pic of the dizzy set-up: http://britautoparts.com/morris-parts/o ... s-catalog/
The feed from the coil is attached to item 7 in the pic. In this type it is attached where you see the little nut but others may have a spade connection.
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Re: No spark

Post by rreems »

Thanks for this! Could you please tell me Is there a single wire going from item 7 in the diagram to which side of the coil?
Thanks

Richard
simmitc
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Re: No spark

Post by simmitc »

Single wire (should be white with a black tracer along its length, but any colour will work!) runs form the terminal on the side of the dizzy to the terminal on the coil that is marked "CB" or (and here's where it gets tricky) the "-" termnal on a -ve earth car or the "+" terminal on a +ve earth car.
Single wire (should be white) from the ignition switch to the terminal on the coil marked "IGN" or the "+" terminal on a -ve earth car or the "-" on a +ve earth car.

Coils are marked either CB and IGN, or - and + because, as you will see above, IGN does not = + or = -, it could be either.

If you're refitting points and condenser, then this article: http://www.spridgetguru.com/TA0084.html might be helpful to follow. When connecting the condenser to the LT and points, take care to have the plastic insulators positioned correctly.
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Re: No spark

Post by oliver90owner »

The contact points are simply a current path to earth, or not, from the coil depending on whether the contacts are closed or open. Nothing more.

The condenser simply prevents sparking at the points surface as the coil current is abruptly stopped (with the associated back emf produced by the sudden collapse of the magnetic field within the coil primary). Excessive arcing would cause rapid degradation of the contacts. With an appropriate capacitance value it also redirects that induced voltage back to the coil windings, to increase the spark energy and duration.

The condenser is fitted between the live side of the points and earth. Energy flows in to, and out of, the capacitor but should not pass current to earth potential.
myoldjalopy
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Re: No spark

Post by myoldjalopy »

OK, Richard - is your car +ive or -ive earth......and what markings do you have at the coil terminals? If we know these two answers, we can tell you how to connect the wires to and from the coil exactly.
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geoberni
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Re: No spark

Post by geoberni »

Irrespective of whether the car is -ve or +ve earth, before going to all the trouble of changing it over to Points, the question remains, is there actually a supply at the coil when the ignition is switched on?

Yes, there's a reasonable probability that the Acuspark unit has failed, but since we don't know the condition of the car, there's also a ruddy good chance that there's a loose cable at A3, or a bad connection at the terminal onto the coil.
Why spend time replacing the points when 10 seconds with a meter or test lamp will tell you if there is power to SW on the Coil?
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pgp001
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Re: No spark

Post by pgp001 »

Richard

The Accuspark unit could possibly fail, but they dont fail when not in use so I dont think that will be your problem.

You recently asked some questions about the car misfiring, and it was a blown head gasket in the end, but it was actually running then.
So I cannot help wondering if you have accidentally pulled a wire out somewhere when you were changing the head gasket.
It seems to be a bit of a coincidence that you are having ignition problems now when it was running before you took the head off.

You really do need to check that you have 12V at the coil when the ignition is on, as Geoberni has already said.
The most common mistake people make is to blunder from one potential fault to another, you must work logically through each one and eliminate it as a possibility before moving on.

Phil
rreems
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Re: No spark

Post by rreems »

Hi thanks for the advice! I’ve literally rebuilt that car, but sadly electrics isn’t a strong point as you may have guessed!
It’s negative earth The coil is market + and -and there Is 12v to the + side of the coil with the ignition switched on!

I replaced the head gsk and she was running so not sure what I’ve done Wrong!
I’ve changed back to points and condenser with one wire coming from the points to the - side of the coil and a white wire going to the + side
Would there be a fuse involved somewhere? Or a separate earth wire?
Thanks
Richard
rreems
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Re: No spark

Post by rreems »

Forgot to mention there is a white wire with black tracer attached to nothing either end
This was attached to the black wire coming out of the Accuspark to the coil, the red wire from the Accuspark went to the other side of the coil but wit the points set up I only have one wire from points to coil
Hope this makes sense
R
myoldjalopy
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Re: No spark

Post by myoldjalopy »

That sounds right for a negative earth car - the wire from ignition going to the +ive connection of the coil and a wire from the -ive connection of the coil to the dizzy. No fuse and no separate earth, the system earths through the points when they close and causes the coil to fire its high voltage through the king lead to the dizzy. So.....if the timing is right, the points are installed correctly, and gapped to 15thou, does she fire up?
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