No power from coil to distributor... (1 Viewer)

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

RevISK

SILVER Star
Joined
May 26, 2020
Threads
27
Messages
1,599
Location
sunset valley, tx
I haven’t been able to get a spark to my plugs, tested with an inline tester. Replaced coil and ballast resistor and still no spark.

Getting power to both sides of resistor and the wires off the coil but not from the plug to the distributor. Check both the cable and the actual outlet (?) of the coil. Nothing.

What am I missing?
Please correct any nomenclature I’m saying wrong.

Thank you in advance.

Ian
 
Oh yeah, 1980 FJ40.
 
ballast resistor on a 1980? is this a foreign rig?
 
This is what was on there and what I replaced.
I believe it’s been in Texas since it’s birth or soon after...

877B1321-323E-4810-9B64-CEBEDC641893.jpeg


394E56B4-4EB1-4D34-8F8B-10971A031D7D.jpeg
 
When it's cranking, the resistor is bypassed. It has full 12v to the coil + via the circuitry of the truck.
It may be cutting the power to the resistor when cranking. A wire directly from bat+ to coil+ then crank it over will test this.
 
When it's cranking, the resistor is bypassed. It has full 12v to the coil + via the circuitry of the truck.
It may be cutting the power to the resistor when cranking. A wire directly from bat+ to coil+ then crank it over will test this.
Tried that, thank you. Still no spark via inline spark tester.
 
what distributor are you running?
original would have ben fully electronic with coil and ignitor.
Good question. It’s what came on it, has points.
No power from coil though, so...
 
is this a new issue?
did this recently run?
any thing else done to it?
"the points tell the coil to fire"
need to check the points and condenser. points could be out of adjustment or burnt
 
gonna need to check the points and condenser. points could be out of adjustment or burnt
But to back up, why wouldn’t I get juice out of the coil? Points look clean haven’t attempted any adjustment though. Just working my way back and forth and noticed a power gap from the coil to the distributor.
 
does the rotor in the distributor rotate when the engine is turned over?
 
@ Ian did it use to run? Did this just happen or is it a first time attempt to get it to run?
I imagine at some point it ran. It hasn’t since I got it, but it was all but free so...
I’ve got it to turn over, replaced the plugs, oil, battery etc...

CDD21146-1C98-4597-B46D-2D5887BC65CA.jpeg
 
I would visually look at a sparkplug connected to the dizzy and crank it over[ with the wire from bat+ to coil +] and look for spark.
Pretty hard for a points system to malfunction, they are so simple. Unless there's a short or broken wire from the points to the dizzy negative.
Juice out of the coil is not constant, its pulses of very high voltage . You probably know this but just in case.
Congrats on the freebie!! looks pretty good.
 
Last edited:
I would visually look at a sparkplug connected to the dizzy and crank it over[ with the wire from bat+ to coil +] and look for spark.
Pretty hard for a points system to malfunction, they are so simple. Unless there's a short or broken wire from the points to the dizzy negative.
I’ll try that, but maybe I’m missing something, if there isn’t power from the coil to the dizzy how would I get spark?
I am an elementary at best mechanic. Closer to kindergarten.
 
if you're talking about the coil high tension center of coil to center of dizzy cap wire, there will be no voltage reading when the engine is not running.
Ah. Well what do you know.
back to the drawing board...
 
Just in case. The coil negative wire goes directly to the points, and nowhere else.
Yessir, one wire from the - side of the coil to the distributor. It terminates there.
 

Users who are viewing this thread

Back
Top Bottom