1978 CJ-7 ignition problems

[pinky]

I am trying to get this moter to turn over AMC 304 v-8 small block auto Transmission I was told starter is relitively newand this looks to be true I replaced the battary and the starter sylanoid and still no luck I am geting power to everything else lights ect any Ideas or sloutions thanks pinky

 

[BusaDave9]

I was told starter is relatively new

I say it's the starter. It's a very simple circuit. If the starter is getting 12 volts it should be turning over the engine unless it's seized.

 

[pinky]

I just replaced stater and still no luck were would the next logical place to look be maybe some whear in the ignition system I am at a loss any help out there thanks pinky

 

[BusaDave9]

Pinky and Panky can't get their jeeps started.
Sorry, I keep getting those 2 threads and names confused.

Lets make sure we understand the problem.
Does your engine crank over? The starting system's job is to turn the engine over with the starter. The solenoid on the fender energies and sends 12 volts to the starter.

If the engine can crank and rotate when you turn the key then the starter is doing it's job. At this point it's up to the ignition system to make sparks to ignite the fuel mixture. If your engine can crank and rotate but still not start then it's a problem with the ignition system (as long as you are getting fuel)

 

[pinky]

Thanks for the input Busa the problem is I get nothing when I turn the key I have replaced the battary-starter syinode-and starter with new ones my lights turn singles wipers ect are working fine could it be as simple as a fuse or may be in the stearing collume ignition switch I am pretty new at this so thanks for the help pinky

 

[cerrajero]

odd test for you
turn key and hold it in start position ( where it should be springing back )
while holding it shift in the reverse

does it go in gear and are the reverse lights on?

that is a standard test for the neutral safety switch
which on the lower column

the other is the ignition switch on the column
which is best tested with a voltmeter

 

[cerrajero]

another neutral safety test is move shift lever around while in start position

example would be
put in the N position hold key in the start now shift (either way is fine)
if you get started or at least hear the selenoid click
then readjust neutral safety position on the column

 

[BusaDave9]

Oh yes, the neutral safety switch. I forgot about that. Since you have an automatic that's a possibility.

Now it sounds like we need to get out a volt meter. If you don't have a volt meter a test light will work fine for this problem.

Put the clamp on a ground or the negative terminal of the battery. We need to test for voltages at the starter solenoid. First put the test light (or volt meter) on the big cable on the starter solenoid that has the cable going to the battery. It is very unlikely you don't have voltage here but its a good test to make sure the test lite is working and you have a good ground.

Next check for voltage on the blue wire on the starter solenoid. Pull that wire slightly off the stud so you can put your test light on the same post the wire is connected to. Have someone try to start the jeep. You should get voltage as the key is turned. If not the problem is before the starter solenoid. 12 volts should go through the ignition switch then through the neutral safety switch and then to this blue wire on the starter solenoid.

If you are getting voltage on this wire then the solenoid should be turning on. To make sure put your test light on the big cable on the starter solenoid that goes down to the starter. That should get voltage as you turn the key.

 

[pinky]

ok thanks for the help guys I crossed the small termainel posts on the stater solenoid with A jumper wire and the starter engaged and turned the moter and it seams to be turning ok but the starter will not disengage without pulling the positive battery lead and every time I reattach the battery lead the stater will engage I still have not tryed the nutral safety test or looked at the ignition switch but I will today I dont have much spare time with too jobs and my knolage is Limited with this so I do thank you for the help thanks pinky

 

[BusaDave9]

I crossed the small termainel posts on the stater solenoid with A jumper wire

The intent was to briefly touch the wire to the post on the solenoid. Whenever the wire is in place the starter will run. Since the starter worked with the jumper that tells us the solenoid and starter are good. The electrical problem is before the starter solenoid. You say you've replace the ignition switch. Since you have an automatic there is a switch to make sure you are not trying to start the jeep when it's in gear. That may be your problem. Remove the jumper and see if it starts in natural. I assume you have been trying to start it in park.


This is where Cerrajero was suspecting the problem was.

another neutral safety test is move shift lever around while in start position

example would be
put in the N position hold key in the start now shift (either way is fine)
if you get started or at least hear the selenoid click
then readjust neutral safety position on the column

 

[pinky]

Thanks for the reply busa I didnt mean to imply that I left the jumper in place on the solenoid just did light touch to engage but starter continualy ran untill I pulled positive lead off battary I have not replaced ignition switch yet but am going to try the nutral safety test you suggested earlyer thanks again pinky

 

[cerrajero]

so we are down to these 2
do you have the spring back when you turn the key?
and does anything come on when you turn the key?

 

[pinky]

were I am at now is the only way I can engage the starter is by connecting the positive lead to the battery no matter what position the key is in when I do this and pour gas in the carburator the motor runs great for a very short time then I have to pull the positive lead off the battery to disengage the starter whats up with that? thanks pinky

 

[cerrajero]

I'm still thinking that either the ignition is bad or the neutral safety switch


testing the neutral safety by "jiggling" the shifter while turning the key
testing the ign by turning the key and making sure it springs back from start

the test i suggested only lets you know if they are in the right position
a volt meter would be the next thing to grab
ignitions are $20
neutral safety $25


both are a little pain to get to unless you are a 3 foot contortionist

 

[pinky]

thanks cerrajero I will look into both ignition switchs and see if I can get things running I sure thank you guys for all the help stay in touch thanks pinky

 

[BusaDave9]

I'm still thinking that either the ignition is bad or the neutral safety switch

Agreed. If I were a betting man I'd say it's the ignition switch.
to verify do as cerrajero suggested. Hold the key to start and move the shift lever around. If you can get it to start when the shift lever is near park or neutral then it's the neutral safety switch.
I am guessing you still won't be able to get it to start. That means a new ignition switch. You can get them at a local auto parts store. It's in the dash and awkward to work on but remove the trim around the steering wheel and remove the bolts holding up the steering column. The steering column wont move down much but it should be enough to replace the ignition switch.

 

[pinky]

Thanks busa I have a little time this weekend so i will try to find it on the collume if you have any more tips for this project send them my way thanks again pinky

 

[BusaDave9]

if you have any more tips for this project send them my way thanks again pinky

The ignition switch is right on top of the steering column just behind the dash. Two screws hold it in place and the connector is on the right. Other than that I really don't have much more to say that I didn't already.

That means a new ignition switch. It's in the dash and awkward to work on but remove the trim around the steering wheel and remove the bolts holding up the steering column. The steering column wont move down much but it should be enough to replace the ignition switch.

 

[cerrajero]

one of the bolts for the ignition

 

[cerrajero]

yellow arrow is the brake pedal
purple arrow is the bottom bolt of the ignition