Hey guys! New to Fords and the forums! I need some help! I bought an 86 Ford E-350 with the 460 (7.5L) in it. I am getting no spark. I bought it, the old owners tried replacing the distributer but didn't know you had to align the distributer with the engine and sold the car for cheap.
Long story short, I bought a new battery for it cause the old one was bad, I've aligned the new distributer that they bought and still had no spark, so I bought a coil and then an ignition control module. Truck still won't start and its driving me nuts.
I've tested the horseshoe plug with a test light, shows that I'm getting power to positive with the ignition on and when I tested the negative coil terminal while cranking, the test light is blinking. I'm going to be cleaning the electrical connectors next while I think about it. Any help would be appreciated!

 

Verify the wiring ignition system wiring before throwing more parts at it. These trucks are now all more then 30 years old with some pushing 40 wirings proving should be the first step before throwing parts at stuff.

Below is the wiring for the DS II system. Just do a continuity test between the module the dist and coil. Check or voltage at the module / and coil in start and run. And verify the system ground.

The system is not complicated and only has 3 parts to make it function the ICM (ignition control module) Dist pick up, and the coil.

if you wan step by step let us know.

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If you have constant power to the coil +, and the negative of the coil is blinking, the coil is making spark. Take the wire off the center of the distributor and hold it close to the engine block while someone cranks the engine. If the above is true, you should see spark. If you have spark, plug that center wire back into the distributor and then check for spark on the plug wires. If you do not have spark, check the rotor and cap and make sure they are ok. And ohm out your sparkplug wires to make sure they are good.

 

P.S. The 460 equipped trucks and vans have a lot of problems with electric fuel pump systems they use. If you have spark, you might want to spray some brake cleaner down the carb and see if it tries to run.

 

Step by step would be great! I am great with mechanical stuff but still novice with electrical.
I'll check the ohms on my wires, I do think some of them needs replacing. So I ended up having my lil bro crank the motor while I stuck a bolt in the wire going to the coil, it sparked once while cranking and then once more when he stopped. I connected it back to the distributer, and checked number 4 spark plug with my bolt and it sparked once on first crank and never really sparked again. Not sure where to check next
I should of said this in the first post, but first thing I did was spray starting fluid down the carb several times. That's when I started checking spark.

I appreciate the replies so far!

 

step by step would be great. I am pretty good with mechanical but electrical is something I need work on. Not sure which wires to test and not sure where I should test the distributer ground from either.

so I had my lil bro crank the motor while I stuck a bolt in the wire going to the coil, it sparked once on first crank then once again when he stopped cranking it. Other than that, no spark. I re-attached the wire from the coil to the distributer and checked the spark at the spark plugs, same thing. It sparked once at first crank then no other spark.

I should of said that's once of the first things I've tried. I sprayed some starting fluid down the trusty ol' carb, no start. So that's when I started looking at the spark

 

Could it be the ballast resistance wire is open, causing it only to spark once in "Start" and no juice in run? Sometimes these ignition switches under the dash start going bad. I would double check all wires, connectors, and grounds. Clean and tight.

Matthew, do you know why Ford decided to use electric pumps with the carbureted 460?

 

Ok Step by step by step
Each steps test point will be labelled on the below diagram. It sounds like you are not getting any Voltage at the ICM during crank so we will start there.
This is not a comprehensive system test but wiring verification. No pick-up coil test is included or coil test is included.


Step 1 Check for Power during crank at ICM on white wire Should be bat Voltage. If no repair circuit, check fuses/links etc
Step 2 Check for power during run at ICM on the red wire should be bat voltage. If no repair circuit, check fuses/links etc
Srep 3 Check of Bat voltage on Coil + during crank
Step 4 Check for Voltage on Coil + during run should be 6-9V
Step 5 Check for ground continuity at the ICM Black wire if it has ground continuity skip to step 8 If not go to step 6
Step 6 Check for continuity on the ground (Black wire) between the ICM and the DIST Points 6 and 5 If no continuity repair wire, if yes go to step 7
Step 7 Check for continuity between Dist plug harness and dist body at ground mounting tab See Pic 2 If no continuity replace pick up, If yes check for continuity between the ground lug and dist body Clean connection if no continuity.

Step 8 Check for continuity Between the Coil and the ICM on the Green wire. If no continuity repair circuit if yes go to Step 9
Step 9 Check for continuity Between the ICM and the dist plug on the Purple wire. If no continuity repair circuit if yes go to Step 10
Step 10 Check for continuity Between the ICM and the dist plug on the Orange wire . If no continuity repair circuit if yes Coil and Pick up testing will be required..


Clean or replace any connectors that are corroded or broken. Connections should be greased with white lithium or dielectric to prevent corrosion.

 

In short, it was done to mitigate vapour lock
The elec pumps have a bypass that helps mitigate the vapour lock issues with the 460 and the higher underhood temps. The engine bay of the 460 trucks is pretty full will emissions gear and AC stuff (when fitted) so there is not a lot of airflow in the 460's and they have higher underhood temps than say a 351W equipped truck..

 

First I wanna say thank you for all that has helped so far! I am getting closer and closer!
2nd, I know how this looks😂 but I was following the steps provided by Matthew and I was looking at the plug with the white and red wires on the ICM and the colors were flipped. So I made some ghetto jumper cables and matched the wires up to their appropriate colors just for testing.
I pulled a sparkplug wire and shoved an old spark plug into it and cranked it and it looks like i am now getting spark!!! BUT it still isn't starting I continued to go through the steps that Matthew provided and everything checks out voltage wise and continuity wise.
Spark plug wires look old so I am going to replace them and hope maybe the wires are giving off weak spark. I am also going to pull my distributer and retime it just to ensure I timed it to TDC compression stroke on cyl. #1. Anything else you guys recommend doing? I did not purchase the distributer so I am hoping 100% that the old owners bought the correct one. I sprayed some starting fluid just to ensure that gas wasn't a variable. Thanks again to all that has helped, these forums are awesome!

 

I have heard some of the aftermarket modules did have the colors filpped, but their function and placement were still correct.

 

Ok time to ohm out the coil . Ohm out the primary side. Terminals on the sides And ohm out the secondary side. The secondary side is from the high tension lead post (center) to the ground (-) on the coil.

Primary on the 200 scale should be. 9 - 1.8 Ω
Secondary 200 Scale should be 6.5k - 13.0kΩ

As for the colours being backwards on the module it "should" not matter it should still start, but, If the coil is weak the and the wires are backwards it may affect it.

 

Alright so I tested the primary coil (positive to negative terminal on coil), its testing @ 1.7 ohms on the 200 scale.
I tested the secondary on the 200 scale as well (middle of the coil to the negative side of the coil) and I am not getting any readings. I used 2 different multimeter and am getting the same results. Would that mean I have a bad coil even tho its brand new from autozone?
I also returned the autozone ICM and got one from Napa just to test it out and no spark still.

 

Shouldn't we use the 20k range with measuring 9-11kohms?

 

In that case I measure 8.17 ohms on the secondary coil!