How to test 81-87 ignition ignitor system (1 Viewer)

[FJ40Jim]

A cross post from a email to a customer:

You can test the complete 81-87 2F ignition system on the workbench.

Supplies:
- A coil & ignitor assembly and a distributor assembly
- a source of 12VDC power. I use a gel cell battery from an old computer battery backup. A car battery or a 12V rechargable drill battery are also good sources.
- test lead wires w/ alligator clips
- clean sparkplug gapped at ~.040"
- known good coil or plug wire
- large vise grip or small c-clamp

Setup:
-remove cap & rotor from dissy.
-insert coil or plug wire into end of coil.
-insert sparkplug into end of coil wire.
-Clamp plug body to foot of coil w/ vise grip or small c-clamp, so that plug gap is visible.

Connections:
-plug ignitor lead into dissy.
-connect -12V lead to mounting foot of coil
-clear the area! connect 12V+ to coil + terminal. ignition is live now.

-spin dissy shaft by hand. spark should be visible & audible at plug.
-disconnect battery. watch out, coil will spark one last time when battery is disconnected.

HTH!

PS: can a mod stick this on the tech page?

 

[thebigredrocker]

@FJ40Jim
Will this test work on an earlier coil/ignitor/dissy? Thank you.

 

[Spike Strip]

@Mace
@Rigger

FAQ please.

 

[OGBeno]

A cross post from a email to a customer:

You can test the complete 81-87 2F ignition system on the workbench.

Supplies:
- A coil & ignitor assembly and a distributor assembly
- a source of 12VDC power. I use a gel cell battery from an old computer battery backup. A car battery or a 12V rechargable drill battery are also good sources.
- test lead wires w/ alligator clips
- clean sparkplug gapped at ~.040"
- known good coil or plug wire
- large vise grip or small c-clamp

Setup:
-remove cap & rotor from dissy.
-insert coil or plug wire into end of coil.
-insert sparkplug into end of coil wire.
-Clamp plug body to foot of coil w/ vise grip or small c-clamp, so that plug gap is visible.

Connections:
-plug ignitor lead into dissy.
-connect -12V lead to mounting foot of coil
-clear the area! connect 12V+ to coil + terminal. ignition is live now.

-spin dissy shaft by hand. spark should be visible & audible at plug.
-disconnect battery. watch out, coil will spark one last time when battery is disconnected.

HTH!

PS: can a mod stick this on the tech page?

Bang!

 

[OGBeno]

I’ve sticky-ed it. Will move link to FAQ once back in front of desktop (unless Mace or Rigger get to it before me).

 

[Rigger]

I’ve sticky-ed it. Will move link to FAQ once back in front of desktop (unless Mace or Rigger get to it before me).

No prob, beno. I'll let you handle it. Thanks!

 

[FJ40Jim]

@FJ40Jim
Will this test work on an earlier coil/ignitor/dissy? Thank you.

For testing purposes, the 78-80 ignitions can also be tested this way. Be aware that there are two power wires into those ignitors: one to coil +, one to power the ignitor. Both get 12V for test purposes.

Anything earlier is more of a PITA to rig up on the test bench because there are ballast resistors and the points go to ground on the engine, which goes back to ground for the coil and the ignitor. Lots of fiddly wires to hook up.

 

[OGBeno]

Unstickied. It has been added to the FAQ.

 

[thebigredrocker]

Thank you FJ40Jim for your awesomeness.

@FJ40newmechanic here’s the test for your 78

 

[Spike Strip]

Now if people would only read the FAQ ....
............................................. ^^ that's a link!