no spark through the dizzy

[SoDakScout]

Hello, here is the specs...
77 traveler with a 345. I beleive the ignition system that is in it is original..."gold box." the problem I am having is the spark plugs will not spark. If I take the center plug wire out and ground it there is a nice constant spark very visable. The coil has three wire that run to it. Only one of which has 12+v when the key is in the "run" state. When the key is in the start or "cranking over" there is still only 12+v to the same wire. The gold box has 5 wires running out of it; two to the dizzy and three to the coil. Is there anyway to ensure that the gold box is not shot? I read in one thread that there should be a wire that has 12+ while cranking and then drop to 6v at the coil. My coils only hot wire stays at 12+. Any help would be great. I will post pics when my computer stops pms'n.

 

[Scoutboy74]

I think you're a little bit mixed up from your explanation, which is not unusual. First thing, are we to understand that there is at present only 1 wire connected to your coil + terminal? That's the way it sounds. There should be another wire connected to that terminal originating from the 's' terminal of the starter solenoid which provides full battery voltage during starter crank only. Once the engine catches and the key is released to 'on', the circuit you've already identified provides the constant voltage necessary to keep then engine running. Without the feed from the starter, the engine isn't going to fire.

 

[Eric VanBuren]

If you get a good spark, one that will jump a 1/2" air gap, from the wire leading to the cap from the coil but no spark at any of the plug wires then you have a bad rotor, cap, or a whole mess of bad plug wires.

 

[SoDakScout]

Ok...I was under the impression that the "starter" power came from the gold box. So that leaves two wires that will be connected to the - side of the coil? One from the two prong plug, and the singal wire leads both from the gold box? I also am going to assume that the lead from the starter should be at least a ten guage? Thanks for the help fellas.

 

[Michael Mayben]

The wiring layout underhood for a gold box system is somewhat different as the wiring used for a breaker point system or even a prestolite electronic ignition system.

No ballasted (or resistor wire) primary feed is used or needed on the primary side.

Hear is a scan of the basic schematics needed for understanding of the electronic ignition system wiring. Disregard the "1974" callout, that does not matter here. This wiring system is different from what is used with a breaker point system that scoutboy74 described. If you attempt a juryrig or bypass when scruuin' with a gold box system you will fry it.

 

[SoDakScout]

Thanks for the scan micheal. I am trying to understand whats going on here.....so there is only one wire that leads to the coil that should have 12v? Also the anti-diesel solenoid is located on the carb correct? Thanks for any help you can provide

 

[Michael Mayben]

thanks for the scan micheal. I am trying to understand whats going on here.....so there is only one wire that leads to the coil that should have 12v? Also the anti-diesel solenoid is located on the carb correct? Thanks for any help you can provide

The solenoid is on the carburetor. And due to po workarounds, you May not even have one mounted. That also is an "emissions" device that was a factory workaround for the crappy drivability (hot engine run-on) that came with 2nd tier emissions regs.

Ya gotta keep in mind...these schematics for the most part are generic for the Scout II across the board. There were many variations under the hood depending upon which engine was oem, which transmission, a/c or not, kalifornia-version or 49 state, oem cruise control, etc. IH did not do a very good job of making this stuff in a manual accurate for each year, that was done by issuing service letters to the dealers and we don't have access to those unless someone has a collection. We do have some of 'em but not complete sets by calendar year of issuance.

The bigger issue here especially for folks new to this stuff....there are many wire runs in the entire vehicle harness that are not connected to anything, just deadheads. Connection again depended upon what accessory items might be installed. And for quite some time, the wiring harnesses contained wire runs for both breaker point ignition and the electronic system variations!! The "alternative" wire runs were simply hidden in the loom and pulled out if needed on the assembly line.

The big change came about electrically-speaking with the advent of the so-called "model year 1977" and later. Again, there are many detail differences in those vehicles and at that point IH did a much better job of documenting the electrical-related schnizz in the mt2313 service manual which is now published in a two volume set. It also has an extensive amount of documentation regarding emissions stuff, drivability, ignition, transmission changes (automatic), etc. By then the whole drivability deal had hit the fan because of the emissions regs and dealership mechanics were in revolt since they faced that shit on the front line!