91 16v no spark

[bt80k]

Hi all I've just sorted out my fuel system but have no spark, I've cleaned the dizzy cap and rotor arm which both look ok and tested the resistance in all leads which were ok too now I had a go at testing the coil but I'm not great with electrics.Has anyone got an idiot proof guide to doing this. Thanks

[cliffcoggin]

Is it old fashioned enough to have points? If so, check the gap and ensure the contact faces are unburnt. The condensers in such systems were also prone to failure.

[bt80k]

15 minutes ago, cliffcoggin said:

Is it old fashioned enough to have points? If so, check the gap and ensure the contact faces are unburnt. The condensers in such systems were also prone to failure.

Not quite it's a coil serving the distributor.

[Magnet]

Other way about Tony. It’s the distributor which ‘serves’  the coil. 

[bt80k]

2 hours ago, cliffcoggin said:

Is it old fashioned enough to have points? If so, check the gap and ensure the contact faces are unburnt. The condensers in such systems were also prone to failure.

Not quite it's a coil serving the distributor.

 

Oh, I always thought the coil sent the spark and the ditributor passed it to the plugs.

[daveyboy1967]

17 minutes ago, bt80k said:

Not quite it's a coil serving the distributor.

 

Oh, I always thought the coil sent the spark and the ditributor passed it to the plugs.

You are correct Tony.

[cliffcoggin]

The LT current flows from the contact breakers to the coil where it is transformed to HT. That HT current goes from the coil to the centre of the rotor arm in the distributor and thence to the spark plugs.

[daveyboy1967]

What Clifford said.

[bt80k]

23 minutes ago, cliffcoggin said:

The LT current flows from the contact breakers to the coil where it is transformed to HT. That HT current goes from the coil to the centre of the rotor arm in the distributor and thence to the spark plugs.

 

18 minutes ago, daveyboy1967 said:

What Clifford said.

So how do I go about testing my coil without removing it.

[Magnet]

Please answer the question Cliff asked Tony - distributor has points and condenser or not- ?

[bt80k]

32 minutes ago, Magnet said:

Please answer the question Cliff asked Tony - distributor has points and condenser or not- ?

Must of missed that Magnet, I've no points just coil to dizzy/ rotor arm

[Magnet]

Thank you Tony. By what I can see you stated you ‘ cleaned the dizzy cap and rotor arm’ - not quite the same? 
I think I’ll dip out of this one. 

[bt80k]

58 minutes ago, Magnet said:

Thank you Tony. By what I can see you stated you ‘ cleaned the dizzy cap and rotor arm’ - not quite the same? 
I think I’ll dip out of this one. 

I'm lost as to what 'not quite the same' means Magnet

[daveyboy1967]

I'm confused too Tony.

[bt80k]

3 minutes ago, daveyboy1967 said:

I'm confused too Tony.

🤣

[bt80k]

 I did some multimeter testing set at 20k with the leads and got 8.5 , 9.2, 10.3 & 11.2 shortest to longest and with the coil to dizzy lead 4.3.

On the coil itself also set at 20k from 1- to lead output 7.8 and set at 200 across terminals 1- & 15+ I got 03.2.

Do these readings seem ok?

[cliffcoggin]

Tony.

We have not established whether you have contact breakers (points) running against a four or six lobed cam in the distributor, or one of the early electronic systems that had some sort of sensor to generate the LT impulses. Naturally diagnosis of the fault depends on which system you have.

As for testing the coil, I only did it the old fashioned way by holding the HT lead in my hand and cranking the engine. It was immediately obvious if the coil was making the expected 14000 volts!

[bt80k]

22 minutes ago, cliffcoggin said:

Tony.

We have not established whether you have contact breakers (points) running against a four or six lobed cam in the distributor, or one of the early electronic systems that had some sort of sensor to generate the LT impulses. Naturally diagnosis of the fault depends on which system you have.

As for testing the coil, I only did it the old fashioned way by holding the HT lead in my hand and cranking the engine. It was immediately obvious if the coil was making the expected 14000 volts!

Hi Cliff I believe it's KE-Jetronic system there are no points involved. I tested the coil firstly by using a lead and cranking no spark from the coil I then removed it and did an ohm test which I'm sure was within the range. Now I'm after where to go next.

[cliffcoggin]

I can't help on that score, except to say you need to find a way to test the output of the LT pulse generator (the Jetronic unit) before worrying about the coil.