Ford ignition help

[raidmagic]

Hey guys,
I'm working on a friends Jeep and I can't get spark after doing a common tune up. You can get a quick spark at you release the key from crank to on but none while in the crank circuit. Now I had this problem before and went back to the lessons I learned then and even ran a jumper from the battery positive to the coil positive and still no spark. I had the ignition module checked at the parts store and it checked out ok.
It's an 84 4cyl jeep with Ford style ignition system, I don't know much about them and am wondering if someone can id this relay and tell me if it's part of the system.
Thanks for any help you can offer.

 

[RPM]

IF you had the cap off, it might have broken a rotor button.

 

[donsrods]

The way Ford does it is that they pull 12 volts from the small post on the solenoid that is marked "I". (one on the right in your picture) Take a test light and clamp it on a good ground and remove the little wire from that post. Touch your test light probe to the threaded post (small one marked "I" ) and have someone crank the engine. The light should stay lit as long as you are cranking. If not, you may have a bad solenoid. If it does light, then something between that post and the + side of the coil is not making contact. Since you just did a tune up, I bet you left that wire off of the + terminal.

Ford then gets the voltage to the coil through the ignition switch "I" terminal and routes that through some resister wire to the coil + side also, but at a reduced voltage.

Don

PS, I just noticed, that solenoid is really cruddy. Clean up all the terminals shiny and clean up the entire area around it. No wonder it won't run. Probably not getting a good ground to that dirty inner fender either. lol

 

[raidmagic]

I've double checked cap and rotor both appear to be in good shape, both are new. I just tested the I post and it has 12v while cranking. The + wire is on the coil and it getting voltage while cranking.

 

[donsrods]

Ok, pull the center wire out of the distributer (the coil lead) and hold the end with some insulated pliers or similar so you don't get knocked on your butt, and hold the brass end about a 1/8 inch from the engine block. Have someone crank it and see if you have spark jumping to the block from the end.


What exactly did you do during this tune up? Did it run before you did it?

Don

 

[Screaming Metal]

RPM and Don have given ya great advice.....double check all thay've told ya................If all else fails.............take the dist. cap off......bump it over till the points are open with one hand......hold the end of the coilwire that goes into the cap about 1/8 fron the block.....and with the other hand short a tip of a flathead screwdriver across the points tips.......you'll notice a spark there.....as you do this....look at your 1/8 gap......when you short across the points.....you should have a nice blue spark...........if not.........you've done something wrong.........

Are you getting any spark at all?????????? If not........a condenser might be bad, or you've got a broken wire between the coil and the distributor...........you should have 12 volts at the OTHER side of the coil. If not.......if your application has a ballast resister.......check it.......

 

[rooster57]

SSM i dont think he has any points.

 

[putz]

here is a wiring diagram for your ignition

Ok, pull the center wire out of the distributer (the coil lead) and hold the end with some insulated pliers or similar so you don't get knocked on your butt, and hold the brass end about a 1/8 inch from the engine block. Have someone crank it and see if you have spark jumping to the block from the end.
I always put it on my tongue instead conducts electricity better.LOL

 

[Screaming Metal]

SSM i dont think he has any points.

OOOOOPPPSS>>>>>>>>>>>>>>>>blame it on the alcohol fumes there buddy...................................yea.....Putz.......put it on him!!!!!



.............................:rofl:.....I'm a dummy at times.................

 

[raidmagic]

Good info thanks
I just tried the coil wire to the block deal and no spark.
As requested here's the whole story.
A friend asked me to work on his hunting Jeep, it won't run. He brought it over and I tinkered the first day, cleaned the carb used some ether and got it to run. It ran bad and had tons of exhaust leaks. Also the Carb was leaking fuel from every gasket so I pulled the carb and bought a rebuild kit.
While doing that I put new plugs, wires, cap, rotor on it. I put the carb back on and put some fuel down the throat to prime it in case the fuel wasn't up top. When I pulled it all apart I forgot and left the key on and the battery was dead so I wanted to fire it up while charging the battery. It fired right up and ran on the gas in the carb but then died. I then realized that the carb wasn't working right, it wouldn't squirt fuel when you pushed the gas. So I pulled the top of the carb back off and corrected my error. When I reassembled it all was when I encountered no spark. I did nothing to the ignition system from the time it ran on the gas in the carb to this point.
Now I don't have spark. I've tried another coil that I had in the shop and I had the ignition box checked at the parts store.


In the above picture it shows a ballast resistor, I haven't looked for or checked one because I though when those went bad they cut power to the coil? Also with it being computer controlled (1983) I didn't think it had one I thought the ignition box did that.
That's all I can think of at the moment if anyone can fill in the gaps that would be great. I'm really lost at this point. My mind is going to the pick up in the dist. but I don't know how to test that.

 

[Duke]

If the resistor is bad, it will start with the key in the start position ( Starter cranking ). When you let go of the key so that it is in the run position the engine will die. The resistor is bypassed during cranking. If it doesn't have spark while cranking it probably is not a bad resistor. Hope that helps some.

 

[railroad]

Just a possibility, I have seen ignition switches that would loose the ignition contact with time. You could hold the key just south of the start position and it would run, but if you let up, it would die. Couldn't you put a test light on the positive side of the coil and watch it as you went through the start procedure?

good luck,
railroad

 

[JOHAN]

Hallo tacke a thin wire direct from the starter then while you crank the motor there will be 12 v on the coil
from Mr-t

 

[raidmagic]

Just a possibility, I have seen ignition switches that would loose the ignition contact with time. You could hold the key just south of the start position and it would run, but if you let up, it would die. Couldn't you put a test light on the positive side of the coil and watch it as you went through the start procedure?

good luck,
railroad

Yes I've done this. Today I ordered a pick up coil for it. It's the only part that wasn't replaced when it was tuned up.

Hallo tacke a thin wire direct from the starter then while you crank the motor there will be 12 v on the coil
from Mr-t

I've tried this, thanks