86 HEI no spark

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Knep115

Junior Member
Joined
Apr 25, 2024
Posts
18
Reaction score
20
Location
Greensboro, Indiana
First Name
Mikel Knepley
Truck Year
1986
Truck Model
Silverado C10
Engine Size
350
It doesn't have one coming from the battery to the cap it has one from the harness to the cap. Disconnect it make a jumper from the battery + to the cap andctry to start it. If it starts you are losing 12v to the distributor in crank position. You will have to remove jumper to shut the engine off,if that's the problem. You replaced every single wire in the distributor? There isn't one in there at all that was there before the problem started?
no sir, I have rebuilt this distributor, the money I spent on parts, I could have bought a brand new one! I'll give the jumper a shot...
 

Knep115

Junior Member
Joined
Apr 25, 2024
Posts
18
Reaction score
20
Location
Greensboro, Indiana
First Name
Mikel Knepley
Truck Year
1986
Truck Model
Silverado C10
Engine Size
350
It doesn't have one coming from the battery to the cap it has one from the harness to the cap. Disconnect it make a jumper from the battery + to the cap andctry to start it. If it starts you are losing 12v to the distributor in crank position. You will have to remove jumper to shut the engine off,if that's the problem. You replaced every single wire in the distributor? There isn't one in there at all that was there before the problem started?
Yes sir, rebuilt this distributor everything but the springs in it. As much as I spent on parts, I could have bought a brand new distributor! I'll give the jumper a shot tomorrow. Just to clarify, your talking about the small one that is next to the tac?
 

Ricko1966

Full Access Member
Joined
Apr 11, 2017
Posts
5,581
Reaction score
9,060
Location
kansas
First Name
Rick
Truck Year
1975
Truck Model
c20
Engine Size
350
no sir, I have rebuilt this distributor, the money I spent on parts, I could have bought a brand new one! I'll give the jumper a shot...
Sorry for your bad luck,try the jumper,but you even replaced the wires going through the side of the distributor body?
 

Ricko1966

Full Access Member
Joined
Apr 11, 2017
Posts
5,581
Reaction score
9,060
Location
kansas
First Name
Rick
Truck Year
1975
Truck Model
c20
Engine Size
350
Yes sir, rebuilt this distributor everything but the springs in it. As much as I spent on parts, I could have bought a brand new distributor! I'll give the jumper a shot tomorrow. Just to clarify, your talking about the small one that is next to the tac?
I'm talking about the 12volt supply wire at the cap by the tach wire provide 12v there right from the battery,to verify you have 12volts there all the time. If you are losing 12v there at crank you won't get spark at crank.
 

vintovka

Member
Joined
Feb 16, 2017
Posts
47
Reaction score
47
Location
or
First Name
vin
Truck Year
84
Truck Model
k10
Engine Size
350
Just for fun did the issue of properly grounding the coil come up? on some coils the ground is just made by one of the top screws passing thru the coil ground to the body.
 

Knep115

Junior Member
Joined
Apr 25, 2024
Posts
18
Reaction score
20
Location
Greensboro, Indiana
First Name
Mikel Knepley
Truck Year
1986
Truck Model
Silverado C10
Engine Size
350
Just for fun did the issue of properly grounding the coil come up? on some coils the ground is just made by one of the top screws passing thru the coil ground to the body.

There is a ground wire from the body to the back of the head, noting off the distributor...
 

Knep115

Junior Member
Joined
Apr 25, 2024
Posts
18
Reaction score
20
Location
Greensboro, Indiana
First Name
Mikel Knepley
Truck Year
1986
Truck Model
Silverado C10
Engine Size
350
Sorry for your bad luck,try the jumper,but you even replaced the wires going through the side of the distributor body?
yes, the ones that attach to the other side of the module, to the cap!
 

vintovka

Member
Joined
Feb 16, 2017
Posts
47
Reaction score
47
Location
or
First Name
vin
Truck Year
84
Truck Model
k10
Engine Size
350
This is what caused me to junk mine
 

Attachments

  • 20240418_172110.jpg
    20240418_172110.jpg
    81.2 KB · Views: 32

vintovka

Member
Joined
Feb 16, 2017
Posts
47
Reaction score
47
Location
or
First Name
vin
Truck Year
84
Truck Model
k10
Engine Size
350
Mine made a lousy connection. hole too big, screw too small and poor connection.
 

Ricko1966

Full Access Member
Joined
Apr 11, 2017
Posts
5,581
Reaction score
9,060
Location
kansas
First Name
Rick
Truck Year
1975
Truck Model
c20
Engine Size
350
yes, the ones that attach to the other side of the module, to the cap!
Wow! Man you have tried hard, I hope the jumper fixes it. Fingers crossed. One last thing seems like the distributor shaft themselves used to lose magnetism and wouldn't trigger the pickup coil I hope that's not the issue.
 
Last edited:

Knep115

Junior Member
Joined
Apr 25, 2024
Posts
18
Reaction score
20
Location
Greensboro, Indiana
First Name
Mikel Knepley
Truck Year
1986
Truck Model
Silverado C10
Engine Size
350
side note, I do have to jack with the tilt steering to get it to turn over! Just thought of that, maybe a short in the column?
 

Ricko1966

Full Access Member
Joined
Apr 11, 2017
Posts
5,581
Reaction score
9,060
Location
kansas
First Name
Rick
Truck Year
1975
Truck Model
c20
Engine Size
350
Disconnect the pickup coil attach a multimeter set in AC scale and have a buddy crank the engine see if you get ac signal. If no it's at the pickup coil, it's been too long I can't remember where the magnets are and no distributor handy to inspect. If you get ac voltage ,hook the pickup coil back up and hook a test light from the tach lead to ground have a friend crank the engine,if the light flashes module is good and problem is on the secondary side.
 

Knep115

Junior Member
Joined
Apr 25, 2024
Posts
18
Reaction score
20
Location
Greensboro, Indiana
First Name
Mikel Knepley
Truck Year
1986
Truck Model
Silverado C10
Engine Size
350
OK, last update for tonight! I tried the jumper from the battery to the terminal, nothing! I plugged in a tac wire, and as soon as I hit it with the test light, the light came on, when my wife cranked it over, it flashed....
 

Ricko1966

Full Access Member
Joined
Apr 11, 2017
Posts
5,581
Reaction score
9,060
Location
kansas
First Name
Rick
Truck Year
1975
Truck Model
c20
Engine Size
350
OK, last update for tonight! I tried the jumper from the battery to the terminal, nothing! I plugged in a tac wire, and as soon as I hit it with the test light, the light came on, when my wife cranked it over, it flashed....
Okay that means pickup and control module are working. So it has to be a wire or something in the cap. So we need to test the coil and make sure everything is installed correctly.
 

Latest posts

Forum statistics

Threads
44,389
Posts
956,157
Members
36,673
Latest member
TiMiller
Top