Well they changed the steering colum the other day and now we have ignition problems. They worked most of the day checking it over and troubleshooting. They finally wired a toogle switch to ignition coil to supply 12v. The truck did start and run for a short time but now its dead. No spark. I want to start over and remove the toogle switch.
At a loss as to what they could have did. Any help with diagrams or other information would be appreciated.
acton mike
10-06-2008, 09:27 PM
if you supplied 12 to the coil for a prolonged period of time then you have burned it out
you may have bypassed the ballast resistoir which reduces voltage to the coil to 6 volts approximately when the engine is running ; it only gets 12 volts when the starter is turning the engine
bookworm
10-07-2008, 04:31 PM
I think you have 2 problems. First, the electrical switch on the column may be out of adjustment. It can be moved up and down on the column. Back when I was doing that tyoe of work, every time I switched out a column I had to adjust the switch. ( this is the switch at the base of the column, has the big plugin. 3 or 4 small screws hold it in place. They can be loosened, and the switch slid up or down). The problem with it out of adjsutment is that the rod coming from your key-switch that activates the internal slide in the electrical switch may not be moving far enough to kick in the starter.
Second, I agree with Acton Mike, by putting in a toggle with 12v, you may have fried the ballast resistor, or the fusible link.
cheaderhead
10-08-2008, 02:02 PM
Thanks for replies.
As I understand it the truck starter would engage but the truck would not start. That was why they jumped 12v to coil. I'll check coil. Do you have a schematic of ignition wiring from switch to coil/distributor? I've looked at connections under colum. It would be hard to mess them up since they just plug in. But it would be nice to know what color wire did what and it's electrical condition while doing it..........
bookworm
10-08-2008, 03:49 PM
Pull that plug out of the switch and take a good look at both. Those plugs/switches have a way of burning inside, melting the contacts, and you can't see it until yoiu pull the plug out and look. Use a lite under there ( maybe it's my old eyes gettin dim, but I can't see squat under them dashes anymore....)
cheaderhead
10-11-2008, 09:33 AM
Got it running. Fusible link was bad that supplied voltage to cab. Most of the wires in that area were a mess. Somebody been picking holes in them. One question remains.....there is a small 18 gage black wire that has 12 volts on it that was sticking out of the harness. (Pointing away from the main firewall connection) They had wire nutted it with the main 12 volt wire that feeds the fusible links. Not sure why as they both had 12 volts all the time. It was cobbled into the 12v wire and did not look like it belonged there. Anybody have any idea what it is for? Going to try and start it this morning cold. If it starts. Nice.
cheaderhead
10-11-2008, 10:21 AM
Dang............no start. Worked great last night while warm. Started and stopped several times. Weak spark. Voltage at coil drops while cranking. Checking connections...........
cheaderhead
10-16-2008, 07:46 PM
Cleaned battery terminals. Installed new ground cable. It started every morning for 3 days. Left it sit for a couple and no start. Slow cranking/low voltage at coil + terminal
I guess on these older ignitions you need a good 12v for start right? If you jump it, it fires right off. Going to have him put a new battery in it. It is charging fine 14.25v.
Any other suggestions short of updating the ignition per some of the other posts?
Chump
10-17-2008, 01:33 AM
Cleaned battery terminals. Installed new ground cable. It started every morning for 3 days. Left it sit for a couple and no start. Slow cranking/low voltage at coil + terminal
I guess on these older ignitions you need a good 12v for start right? If you jump it, it fires right off. Going to have him put a new battery in it. It is charging fine 14.25v.
Any other suggestions short of updating the ignition per some of the other posts?
Sounds like a bad battery or you have a drain on it. Have the battery load tested or replace it with a new one. Truck should start with 10 volts or a little less and proper amps for the starter.
1972-D100
10-17-2008, 09:46 AM
You may also have a bad diode in the charging system which would cause a drain over a couple of days of sitting, you can usually get it checked at the local parts store when they check the load on the battery.
cheaderhead
10-17-2008, 04:32 PM
Well.....after I got it running the other day I determined that it wasn't charging. Had alternator and regulator checked. Alternator was not working. Regulator was fine. (according to parts store) anyway......replaced both alternator and regulator with new. As always I have them checked before leaving the store. Charging fine now. I'll have him throw a new battery in it.
It's like it needs that extra little bit to produce decent spark. Just hooking jumper cables to it without the donor engine running is enough to kick it off. Is it just a dodge thing that you have to have a solid 12v for start?
1972-D100
10-17-2008, 04:53 PM
Not on mine, maybe the starter motor is getting worn out and pulling more power to get it to kick. I've start mine with as little 10V. May have a bad starter relay as well.
