34 replies to this topic

[jezjsa]

So I’ve just changed the Lumenition module to a previous one I had - still won’t spark.

 

The checking continues…

 

So far :

 

I am getting power from the live feed from the fusebox to the coil.

If I place a test light on the + of the coil I get it to light up.

I’ve removed all spark plugs and turned engine over a few times. Then refitted them.

Now changed the coil to a spare one.

Changed the Lumenition module ( I had an older one ) in the distributor in case it was that - since I put the wires from this module on the wrong way at the coil!

I’ve taken the ht lead off the distributor and placed near the stud bolt… turned over engine and no spark.

 

What else can I now check?

[sonscar]

Disconnect the coil negative and put a small lamp in series with the coil terminal and the removed wire.Turn on and rotate the engine and the bulb should flash.This should prove the module which is just an electronic switch.You have fitted the rotor?Steve..

[jezjsa]

Disconnect the coil negative and put a small lamp in series with the coil terminal and the removed wire.Turn on and rotate the engine and the bulb should flash.This should prove the module which is just an electronic switch.You have fitted the rotor?Steve..

 

Im assuming you mean the negative wire from the distributor module? or both negative wires as there another one too..

 

Hey Steve - ive just seen your in Crowle .. is that the South Yorkshire version or the Worcester version. As im in Epworth (sYorks)

Edited by jezjsa, 27 February 2024 - 02:45 PM.

[jezjsa]

Disconnect the coil negative and put a small lamp in series with the coil terminal and the removed wire.Turn on and rotate the engine and the bulb should flash.This should prove the module which is just an electronic switch.You have fitted the rotor?Steve..

 

ok just tried this and the test light lights stays on with ignition and stays on when turning over the engine. It doesnt flash. So does that mean the module is not working?

So that was me taking off the negative wire from the module that was on the coil, attaching my test lamp to it, and then the earth side of the test lamp to the negative coil terminal. Is that correct?

[bpirie1000]

Is the engine earthed alright? Try a jump lead on block and one on earth for body.

Would also suggest using points. Much simpler system and can trace the wires all the way with no boxes of magical electronical dooda's

Edited by bpirie1000, 27 February 2024 - 08:06 PM.

[Steam]

Measure the primary ohms on the coil. Low ohms
Measure the coil secondary mid to high k Ohms
Wire coil and test by shorting -ve to earth and see if spark from coil lead held near block.

[Lplus]

 

Disconnect the coil negative and put a small lamp in series with the coil terminal and the removed wire.Turn on and rotate the engine and the bulb should flash.This should prove the module which is just an electronic switch.You have fitted the rotor?Steve..

 

ok just tried this and the test light lights stays on with ignition and stays on when turning over the engine. It doesnt flash. So does that mean the module is not working?

So that was me taking off the negative wire from the module that was on the coil, attaching my test lamp to it, and then the earth side of the test lamp to the negative coil terminal. Is that correct?

 

On the basis that you mean the black wire connected between coil and distributor, then yes.  The switched power supply should be the red wire from the loom to the coil positive terminal and the red wire from there to the distributor is the power supply for the electronic ignition.  The black wire from coil negative terminal back to the loom is the sensor wire for a rev counter.

[jezjsa]

Measure the primary ohms on the coil. Low ohms
Measure the coil secondary mid to high k Ohms
Wire coil and test by shorting -ve to earth and see if spark from coil lead held near block.

 

Bit more testing done...

 

1. Put a jump lead from the body earth nut/bot to one of the studs on the block.

​Checked there was continuity between this new eared jump lead, read 1 and beeped.

 

 

2. put a wire from the body to the negative terminal of the coil, put a spark plug in the ht king lead and placed against head bolt, turned over the engine - no spark.
Checked there was continuity between this new eared wire, read 1 and beeped.

 

3. measured the coil:
Coil, primary measures 2.6 when setting multimeter to 200.
Secondary measures 6.87 when set at 20k.

I have a spare coil which reads
Primary measures 2.6 when setting multimeter to 200.
Secondary measures 9.61 when set at 20k.

 

 

4. Battery is reading 12.79v across the terminals.

5. Took the ht king lead off and put the multimeter to Continuity and probed both ends, it jumps from 1940 to 1998, doesnt go to 1 or beep.

6. Then put the 20k ohms setting on and it read 1.94.

 

Does this mean its the ht leads?

 

Or is there other checks i need to do?

 

Ive order a new Lumenition module too.

Edited by jezjsa, 28 February 2024 - 07:59 PM.

[Steam]

Coil primary is a little low but it should be fine.
Secondary fine.
Your point 2. You missed the drift here. With 12v to coil you should get a spark when you earth the coil, no turing of engine needed. Each time you earth, 1 spark should be strong and bluish white not orange. You are doing the job of the points/ module manually.

[jezjsa]

Coil primary is a little low but it should be fine.
Secondary fine.
Your point 2. You missed the drift here. With 12v to coil you should get a spark when you earth the coil, no turing of engine needed. Each time you earth, 1 spark should be strong and bluish white not orange. You are doing the job of the points/ module manually.

 

Ah thanks Dave - ok so now done THAT test correctly and i am getting spark to the spark plug on the end of the HT king lead - when i ground the make-shift cable from negative coil to ground.

So that means power is getting from the battery - to the coil - and out of that main lead to a spark plug.

So does that mean, potentially, the issue lies with the lumenition module inside the distributor?

Or is there anything else i can check whilst i wait for the new one to arrive?

Thanks for all your help guys - learning a lot!!!

[sonscar]

Small point,earthing the coil charges it up.Removing the earth causes it to fire.The points are a switch that turns the earth on and off as each lobe passes.All electronic do dad's do is switch the earth on and off.Steve..
Near Epworth.

Edited by sonscar, 29 February 2024 - 10:08 AM.

[jezjsa]

Ive replaced the lumenition module for a new one. 

 

Still no spark at spark plug when testing one of the 4 leads.

 

BUT i do get spark from the ht king lead when earthing that and placing near the block with a spark plug in the end.

Is it that the module just needs to be closer to the centre of the distributor?

 

As something is just not passing the spark through it currently.

 

 

Attached Files

•  distributor.jpg   67.22K   1 downloads

[jezjsa]

Scrap that… the new module and cleaning the rotor arm with sandpaper seemed to do the trick!

[jezjsa]

For anyone having ignition problems, along with everyones advice in this thread, i wanted to better understand the ignition system in sequence from the power leaving the battery to finally creating a spark at the spark plug - so i asked ChatGPT.

This it what it came back with, which massively helped me figure out where the problem was - and hopefully it can help someone else in the future.

Ignition Sequence:

1. Battery: Power originates from the car's battery, which provides the electrical energy needed for ignition.

2. Ignition Switch: When you turn the key in the ignition switch, it completes the circuit and allows electricity to flow from the battery to the ignition system.

3. Ignition Coil: The power travels from the ignition switch to the ignition coil, a transformer that steps up the voltage from the battery (typically 12 volts) to a much higher voltage needed to create a spark (thousands of volts).

4. Distributor: From the ignition coil, the high voltage electricity travels to the distributor, a device that distributes the spark to the correct spark plug at the right time.

5. Distributor Cap and Rotor: Inside the distributor, the rotor spins and makes contact with the distributor cap. The high voltage electricity travels through the rotor and distributor cap to reach the spark plug wires.

6. Spark Plugs: The high voltage electricity finally reaches the spark plugs via the spark plug wires. When the electricity reaches the gap at the end of the spark plug, it jumps the gap, creating a spark that ignites the air-fuel mixture in the engine's cylinders, starting the combustion process.

[KTS]

not bad, but has missed a crucial part of the system, namely the points or switch module without which you won't get a spark (..as you discovered)