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Won't start! New wiring harness issues.

Fitz24

Bronco Guru
Joined
Jul 4, 2007
Messages
1,299
Finished installing a new centech harness, except for the lights. Everything was pretty easy until I got to the duraspark ignition wiring. The instruction leave a little to the imagination. I'm not totally uneducated about wiring and the principles but something is not correct in my work as evidenced from it not starting.
From the diagrams I got off CB, Fordfuelinjection.com, and the centech instructions everything seems to be wired correctly. After some trouble shooting this is what I get.

1. The motor turns over fine.
2. Motor ran fine when I began the project a little over a year ago.
3. Running stock 75 ignition system with voltage regulator, ballast resistor (came with new harness), contol module and dizzy.
4. Blue ign pwr wire from harness to ballast resistor has 11.89 volts with key in run position.
5. Red Power wire on module has the same 11.89 volts with key in run position.
6. Oposite side of Ballast Resistor has 6.06 volts (measures 1.5 ohms accross resistor).
7. I terminal on starter solenoid has 6.06 volts with key in run position.
8. + ign coil has 6.06 volts with key in run position.
9. Violet wire connected to S terminal of solenoid gets enough to ingage solenoid to spin motor (didn't have enough hands to measure while turning key to start position. Couldn't find my test leads with clips.).
10. 1.5 volts accross the orange and violet wires from the module.
11. Measured ohms accross orange and violet on dizzy and it showed open. Still need to verify the installation of the new connector used on the input wires to the dizzy.
12. Harness that I made that connects module to dizzy shows continuity as it should to proper connectors on other end.
13. Black wire from dizzy connected to black on module (should it also connect to chassis ground?).
14. I think I am missing a bypass wire which I think from the diagrams should run from blue ign pwr wire to I terminal on starter solenoid?

Sorry it is long but wanted to supply as much information as I could. I know all the knowledge on this site with help me find what is wrong. Need to have this thing ready for OCBR!

Thanks for any help.
 

cgbexec

Bronco Guru
Joined
Sep 19, 2006
Messages
2,071
Loc.
Naples, FL
Call Centech. they can walk you through it. I had an issue hooking up my HEI Distributer and they basicall told me hook this wire to that and eliminate this wire and connect that to that. Everything worked perfectly. They are helpful on the phone.
 

Viperwolf1

Contributor
electron whisperer
Joined
Aug 23, 2007
Messages
24,346
11. Measured ohms accross orange and violet on dizzy and it showed open. Still need to verify the installation of the new connector used on the input wires to the dizzy.
13. Black wire from dizzy connected to black on module (should it also connect to chassis ground?).
14. I think I am missing a bypass wire which I think from the diagrams should run from blue ign pwr wire to I terminal on starter solenoid?

#11 is your problem. Should be 400-800 ohms. Get a new stator.

#13 It connects to engine ground inside the distributor.

#14 See the diagram.
 

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Fitz24

Fitz24

Bronco Guru
Joined
Jul 4, 2007
Messages
1,299
Called Centech and the person I spoke with said that I have checked everything and suggested I check connections and of course the pickup coil resistance again.

Having been a electronic technician in the past, I should have thought about the first thing I learn as a tech. 99% of problems arise from a bad connection somewhere. Mine was the new connector I installed on the dizzy. I could read 0 resistance from the terminal of the connector to a spot along the wire with a pin stuck in the wire of both the violet and organe wires. For some reason though, I could not get a resistance reading between the to terminals of the connector. So I pinned the orange wire and measured the resistance to the connector terminal of the violet wire. Measure 650 ohms. OK now I'm getting somewhere. Measureed between the connectors terminals for the orange and violet again, still could not get a reading.

Decided to try putting another connector on the wires for the dizzy. Bingo, have my 650 ohms. As I don't have a gas tank yet, I poored some gas in the carb and turned the key. Started up pretty quickly for having sat for almost a year (I did pulled the coil wire previously and spun to get oil circulated first).

Now I'll install my new tank and let it run some to make sure the charging system is working properly.

Thanks for the responses.
 
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