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[JamesV6CDX]

Markie's 1.3 Overhead Valve escort won't start! It just conked out and died with no warning while driving down the road.

We have determined that we have fuel and compression... we have no spark.

Coil has been replaced.

We have proved power to the coil.

We've proved good earth's everywhere.

Distributor is turning.

Cap and Rotor arm look OK

Condensor is new.

When you wiggle the rotor arm, you can see a spark at the points.

We're not really sure what to look at next! Any idea's / Tests? Engines don't get more basic than this.. we should be ashamed

[ClarCE]

Markie's 1.3 Overhead Valve escort won't start! It just conked out and died with no warning while driving down the road.

We have determined that we have fuel and compression... we have no spark.

Coil has been replaced.

We have proved power to the coil.

We've proved good earth's everywhere.

Distributor is turning.

Cap and Rotor arm look OK

Condensor is new.

When you wiggle the rotor arm, you can see a spark at the points.

We're not really sure what to look at next! Any idea's / Tests? Engines don't get more basic than this.. we should be ashamed

Do distributers put out a certain amount of charge to the plugs?  Is that said charge high enough?

[JamesV6CDX]

Markie's 1.3 Overhead Valve escort won't start! It just conked out and died with no warning while driving down the road.

We have determined that we have fuel and compression... we have no spark.

Coil has been replaced.

We have proved power to the coil.

We've proved good earth's everywhere.

Distributor is turning.

Cap and Rotor arm look OK

Condensor is new.

When you wiggle the rotor arm, you can see a spark at the points.

We're not really sure what to look at next! Any idea's / Tests? Engines don't get more basic than this.. we should be ashamed

Do distributers put out a certain amount of charge to the plugs?  Is that said charge high enough?

Not sure how we would test.... distributor is completely mechanical!!

[Admin]

You have proved power to the coil, but no spark?

Checked for spark from coil to distrbutor?

I suspect either lead is broken, or the coil is duff.

[JamesV6CDX]

You have proved power to the coil, but no spark?

Checked for spark from coil to distrbutor?

I suspect either lead is broken, or the coil is duff.

Spark from coil to Dizzy... or course!!

Coil is brand new

[Markjay]

You have proved power to the coil, but no spark?

Checked for spark from coil to distrbutor?

I suspect either lead is broken, or the coil is duff.

As it's low-tech engine, you should be able to check the HT spark between the coil and distributor by holding the HT lead with insulated pliers at either side (one side at a time) and pulling it slightly in and out from the socket to see the spark.

If there is a spark, then you can do the same for each of the four HT leads on the outer side of distributor cap, to see if the distributor actually delivers the spark to the plugs.

Once to determine where the HT spark stops, you should have the culprit...

[Admin]

Naah, just tell Markie to hold the coil lead then turn the engine over. That will quickly determine if there is a spark there....  

[Kevin Wood]

I have replaced condensors before only to find I have put a duff one in!

Check the voltage at the negative LT connection on the coil (the one that goes to the points) with respect to the battery negative terminal. It should be close to 12v when points are open. When the points are closed it will either be close to zero or, if there is a ballast resistor in the circuit, 6 or 8 volts or so. Sometimes the LT lead incorporates a ballast resistance and these can go open circuit.

If the LT side is OK as Laidback66 says, it's got to be a faulty coil (then again, you've replaced that) or a failure in the HT leads / dizzy cap / rotor arm. Pull off the centre HT lead from the dizzy cap (the one that comes from the coil) and see if you can draw a spark from this while cranking. If so, I'd suspect the dizzy cap or rotor arm. If no spark here maybe this HT lead is bad or the coil is bad.

Try measuring the resistance of the HT leads with a digital multimeter. They will typically have quite a high resistance, maybe 5000 - 20,000 ohms if they are suppression leads. Check they are all roughly the same, bearing in mind the longer ones will have higher resistance.

Other than that, there's not much more to go wrong. Have you tried a paper clip test?  

(I.E. Get Markie to hold a paper clip in the coil ht socket and crank. If you have to collect him from the other side of the garage, coil is fine )

Bear in mind that the spark plugs might be a bit damp when you do sort out the spark so crank it over with a wide open throttle or better still, take the plugs out and dry them out in a gas flame (SWMBOs gas hob is good for this, when she's not looking).

Kevin

[Markjay]

Naah, just tell Markie to hold the coil lead then turn the engine over. That will quickly determine if there is a spark there....  

You mean the audible test system that is based on a high-pitched noise when spark is present...?

[Markjay]

I have replaced condensors before only to find I have put a duff one in!

Check the voltage at the negative LT connection on the coil (the one that goes to the points) with respect to the battery negative terminal. It should be close to 12v when points are open. When the points are closed it will either be close to zero or, if there is a ballast resistor in the circuit, 6 or 8 volts or so. Sometimes the LT lead incorporates a ballast resistance and these can go open circuit.

If the LT side is OK as Laidback66 says, it's got to be a faulty coil (then again, you've replaced that) or a failure in the HT leads / dizzy cap / rotor arm. Pull off the centre HT lead from the dizzy cap (the one that comes from the coil) and see if you can draw a spark from this while cranking. If so, I'd suspect the dizzy cap or rotor arm. If no spark here maybe this HT lead is bad or the coil is bad.

Try measuring the resistance of the HT leads with a digital multimeter. They will typically have quite a high resistance, maybe 5000 - 20,000 ohms if they are suppression leads. Check they are all roughly the same, bearing in mind the longer ones will have higher resistance.

Other than that, there's not much more to go wrong. Have you tried a paper clip test?  

(I.E. Get Markie to hold a paper clip in the coil ht socket and crank. If you have to collect him from the other side of the garage, coil is fine )

Bear in mind that the spark plugs might be a bit damp when you do sort out the spark so crank it over with a wide open throttle or better still, take the plugs out and dry them out in a gas flame (SWMBOs gas hob is good for this, when she's not looking).

Kevin

Also... disconnect the spark-plug-side HT leads one at a time and hold them near the cylinder head metal part (not on the spark plug itself), check for spark...

[JamesV6CDX]

Naah, just tell Markie to hold the coil lead then turn the engine over. That will quickly determine if there is a spark there....  

 

Presume,. could just put a spark plug on the end and earth it...

[Kevin Wood]

Presume,. could just put a spark plug on the end and earth it...

You could do. Not as much fun though  

I tell you what. Ask Markie what he'd prefer.

Kevin

[Martin_1962]

What they say - however do the following.

Make sure battery is well charged.

Points should not spark.

Make sure plugs not fouled.

Test with plug on cylinder head to see if it sparks.

You may have damaged a lead while changing coil.

Check all fuses.

[Kevin Wood]

Points should not spark.

This is true, and it indicates a faulty condenser if you're getting significant sparks at the points.

Kevin

[stevief]

This may not be the problem but it's worth knowing about if all else fails.

Fords of that vintage sometimes had ballast resitors fitted into the wiring between the ignition switch and the coil which when they became faulty gave the indication that the coil had failed.

The classic symptom was that the engine would just stall for no reason and would re-start after letting it sit a while, which required longer at each stall until the car would not start again. In the worst case it just failed and as the suspect was the coil you went and bought a new one only to find there was no change.

The usual resistor looks like a length of thicker wire in the line between the switch and the coil and may be under loom tape just to make it more difficult but is just a case of splicing it back in, if I remember right Ford were supplying them with bullet connectors as they were so prone to failure.

Steve