84 CJ no spark from coil

[Techlight]

So I was wrong ...voltage is 10 on start at the solenoid and all connections across the solenoid. Is this still too low?

I was planning on doing it anyway so I just went and grabbed a post style coil to eliminate that horseshoe clip.

This is the CJ with the Howell FI and i verified it has 12 volts to the computer.

I have verified that it's spraying fuel during cranking.

I'm still stumped why it won't give spark off the coil.

Sent from my SM-G950U using Tapatalk

 

[Torxhead]

I would agree on too low voltage, if your volts are too low under operation, you would have got a code 22. My guess would be to check the circuit that provides that 12v to the coil at startup. First looking for bad connections, soldering them to make sure. You might have a loose connection for the run circuit since it was running when it stalled. That resistance wire connection in the run circut must be crimped since it is of a material that cannot be soldered. Good hunting!

 

[Posi]

So I was wrong ...voltage is 10 on start at the solenoid and all connections across the solenoid. Is this still too low?

I was planning on doing it anyway so I just went and grabbed a post style coil to eliminate that horseshoe clip.

This is the CJ with the Howell FI and i verified it has 12 volts to the computer.

I have verified that it's spraying fuel during cranking.

I'm still stumped why it won't give spark off the coil.

Sent from my SM-G950U using Tapatalk

Your getting 10v at the solenoid, is it the same voltage while cranking at the "I" post wire and the + side of the coil?

A 6 cylinder will use AMC 150 -180 amps while cranking. That would be a .5v drop. If your battery is fully charged at 12.6 you should find 12v or in this case 12.1v at the + side of the coil while cranking.

As I mentioned you have a voltage drop. You need to find and correct your voltage drop. It could be a bad connection or poor ground.

However, you should still see a spark at the coil wire. I've started 8 cylinder engines on 9v to 10v in the past. It would be a fat yellow weak spark apposed to the thin blue crisp spark (depending on what your grounding it on color may not matter).

The coil, 7mm wire, and connections should be inspected. If you have 10v at the coil while cranking you should see spark although weak.

Disconnect the wires to the coil. Use Ohms meter on the + and -, should be between 1.13 to 1.23 ohms. Also check the tower to the + and - sides. The coil needs to be warm before testing I take mine indoors for a few hours. Your on the west coast so I'm thinking the temps outdoors are fine. The coil needs to be at 75 degrees. Heck, its in the 40s during the day here with 3" of snow expected tomorrow.

 

[Techlight]

So after considering my options I gave up and took it to a shop. Turned out to be the gear on the distributor. Funny to cause I popped the cap and verified that the rotor was turning which it was. The gear must have been worn down just enough to skip around I guess. Go figure. Either way I promptly took it home and removed the top since it was 82 today. I know lots if folks have snow but we have sun here.

Thanks all for answering my questions and helping me out. It's always appreciated.

Sent from my SM-G950U using Tapatalk

 

[gert]

Wow


Sent from my iPhone using Tapatalk

 

[Torxhead]

Yikes! it would be a good plan to check the mating gear on the cam.

 

[mtnwhlr]

Yikes! it would be a good plan to check the mating gear on the cam.

 

[Lumpy Grits]

Agree 110% about the cam gear!
Get that engine oil & filter changed, ASAP and PRAY......
How easy does the dizzy shaft turn?
How many miles on this dizzy?
Take the drive gear off your OEM dizzy(hope you still have it)and do what it takes to install on this one.
What shop is this?

It's only 77* on my side of town.....
LG

 

[Posi]

Good to hear its repaired.

Unless I'm missing something this thread was about no spark from the coil.

How does repairing a distributor gear down stream of the coil give you spark at the coil?

 

[mtnwhlr]

Good to hear its repaired.

Unless I'm missing something this thread was about no spark from the coil.

How does repairing a distributor gear down stream of the coil give you spark at the coil?

 

[Belizean]

..............