1986 Ignition Problems

1986 Ignition Problems


Orlando, fl
86 cj7 4 cyl 4 speed
not to get in your post but im having problems with my 86 CJ7 4cyl too. cant get it running and its making nuts already. im a nowbie could you help. i bought it couple months ago and wanna restore it. ok first it had a bunch of water in gas tank(it didnt have the gas lid for months i guess). it wont start. ive made it new pretty much. things ive put new so far:

tank sending unit( also emptied the gas and put new gas)
fuel hoses
fuel pump
fuel filter
open and cleaned carb
spark plug wires
ignition module
starter solenoid
ignition switch
key ignition
and thats it i think

when i bought it i disconnected the fuel hose before the fuel pump and put a little gas tank and it started nice and calm(better than my daily driver). i havent adjusted the ignition switch i guess( before i bought the switch, the switch rod used to get stuck and didnt want to spring back. dunno if it still does it). i took the plugs off the ignition switch and wired an universal key switch from autozone to try to start it and nothing. i have to play with the key switches to crank it( ive tried 3 key switches and 3 solenoids) until it cranks(like the solenoid is stuck or the switch doesnt make the right contact).
i put the key in start position, i get spark and gas(feels like i wants to start):) i put gas directly inside the carb and wants to start more(even get some smoke out tail pipe):D. as soon as i put the key in run position i stop getting sparks at the spark plug wires and suddenly the engine doesnt feel like starting :(:confused::mad::censored:.
what do you think guys? i think on doing a nutter bypass to cut out the computer too, should i?
any help, thoughts would be greatly appreciated since i just feel like burning the damn thing by now :eek:
Re: 1980 CJ7 ignition problems

the ignition may not be your problem but
a few test on what you have down here
rod sticking---remove ignition then turn key
---you should have no resistance in turning the key
then reinstall as high on the column that the bolts and slot on switch will allow
does the key go to accessory? and does it spring back?
doing all that you just tested the key, rack, rod, and position of the ignition,
after that i would start on the wiring which i can guarantee 200% that someone on this forum is more knowledgeable than I am on that :notworthy:
but look at this it may help
Re: 1986 CJ7 ignition problems

cool thanks nice diagram. let see if i can figure something out. are there any relays other than whats in the pic?i just wanna know if there something i should be aware of besides whats in the pic
thanks A LOT
Ive never seen that pic
just to make sure about the solenoids wiring, the small red wire goes on the "I" next to the big red wire that goes to the batt, and the light blue goes to the "S" next to the starter cable,right?
Re: 1980 CJ7 ignition problems

just took this pic
trying to figure out how to "cut and paste" this for a new thread
I believe that you will get more responses
Re: 1980 CJ7 ignition problems

ok so double checking. according to the pic from left to right it goes big black cable for starter- then light blue on "s"-red on "I"- and big red for batt and 2 brown for the alternator on the last pole, right?
i think i found the problem. ill test it out tomorrow morning:eek:. maybe you know. when i bought it had a 1 of the 2 positive cables that went from the coil to the carb electric choke and the other to the starter solenoid. this doesnt make sense to me but i didnt notice it because it looks factory so i didnt mess with it until today that i looks at diagrams all day:eek:. well according to the diagram i found that the cable the went to the carb is supposed to go to the switch that way the coil stays with power in the run position.
im my right or completly lost?please clarify this for me.
it makes sense to me and im dying to test it but its kind of late to be cranking or the neighbors are gonna be cranky :D.sorry im getting stupid from breaking my head with this cj already.

oh and if that positive cable from coil to carb doesnt go there, what cable is really supposed to plug into the carb?
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So when you turn the key the engine turns over but won't start. If so it's not the starter solenoid or any of those wires.
The problem is either no spark or no gas.
If it sounds like it is more likely to start when you put gas into the throat of the carb then I think that's where your problem is. It sounds like it's been sitting for a while. The carb may need to be rebuilt. The gas in it may have tared up. When you pump the gas pedal the accelerator pump should squirt gas into the carb. Does that happen?
i took apart the carb and cleaned it. i pull a spark plug wire and stuck a screwdriver in it to check spark while cranking and i get but as soon as i put the switch on run position i stop getting spark. like it cuts off complety power to the coil. i put the gas directly in carb while pumping pedal(and carb does squirt) and ONLY while cranking keeping starter on the engine feels like it want to turn on (even get smoke at tailpipe), as soon as i switch to run position everything dies.
i dont know if got the solenoid wired wrong or what. i put the new solenoid the same way as the old one when i bought the jeep. plus ived tried all kind of combinations on it.
i have little red wire on "S" next to big red to batt and 2 brown for alternator , and blue on "I" next to big black to starter(thats how it was, plus ived tried everything else)
the diagram i found has big red with 2 brown then blue on "S", then little red on "I", and black to starter. but when i do it this way, when i switch to run position the engine cranks, without putting it on start position). so i put it back how i had since it at least cranks only on start position.
is this right?
i need to confirm coil wire charges. green is- and red +?cause i put my tester light in +batt and other end on coil+ and it lit up.
if i put a wire directly from + batt to coil+ and crank it, it should start no matter what, right?
i was wonna do more testing but my battery died since ive been cranking all day yesterday. so im charging it now on my truck.
my little blue wire is hot in run along with the little red wire thats dim in run. when i switch to start little red is hot not dim, correct?
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ok i just fired it up. i left the solenoid like i had it and disconnected the little red wire. i put a wire directly from + batt to coil +. crank it and wa lla. tested both terminals from coil plug by putting test light on batt+ and it lit up. so im getting grounds from both green ground (coil) and red ++++(coil).
big question now is why is there - on + red.
whats the diagram for the ignition switch plugs? that way i can run a cable from the switch to coil directly
So when you put 12 volts on the + terminal on the coil the jeep started up.
That sounds like the ignition switch cerrajero suggested at the beginning of the thread.

cerrajero also has a good diagram of the ignition.

The red wire on the coil should have 12 volts whenever the key is on. A bad ignition switch could cause you to loose 12 volts when you relax the key back to the on position.
well i had the original switch on the original steering column and same thing happened, so i put a brand new ignition switch- same thing happened-i bought another steering column(gonna convert to power steering) with also has a switch- same thing happened-, i bought a universal key switch from autozone, made all wiring-samething happened. so dont think is the switch.
only get volts from little red wire on solenoid to coil when in start position, NEVER from switch to coil, just ground.
which wire goes from the switch to coil(+)?ive been trying to test the 2 plugs that go in the switch but dont know which one it is. i wanna track it to see if its split or something and grounding.
all i know is that direct volts to coil works
maybe a shot in the dark
but when i look behind the dash on my cj I see all kind of aftermarket connectors all of which can come disconnected ( i have had 4 that did)
I'm still PO'd at the PO :mad:
you never know
i am looking in my books for the wire your looking for
guessing would say 2nd from the floorboard on the ign
but DON'T trust a guess on wiring
take a look
I'm confused. The red/white wire to the coil sends 12 volts when the key is in the start position. The engine can start. This means the wire to the coil is good.

Then you relax the key to the run position. Now you loose 12 volts from the coil. That sure sounds like the problem is the contacts in the switch. But you have replaced the switch.

If you put 12 volts on the + terminal of the coil the engine starts.

Panky do I have it right?
I will check my wiring diagram soon to verify the wire is red and white.
i found the problem. solenoid had bad connection. plug my columns switch and bam it turn freely:notworthy::chug:

you know jeeps like crazy
:) im still a newbie but i fill like i learn everything on this one since i had to check everything
i wont have done with your diagrams and stuff
the guy i bought from put the solenoid wrong = no ground kept trying to start. fried the starter. left out getting rain for i dont know how long without the gas cap. got water in tank and mess up everything after that.
thank you again
ill post pics when i get it running how it should since its not taking gears. i open up the tranny by the shifter top and theres also water in it. so i gonna have to drain it and put new oil and see if it wakes up.

anyone had a problem like this?:confused:
Good to hear you got it going.:chug:
Now it sounds like you'll be replacing the oil in your tranny. I would also replace the oil in your transfer case. They both have a drain plug down low. Then they both have a fill plug up higher. Fill it until oil comes back out the fill plug.
It would also be a good idea to also replace the oil in both differentials. Remove both differential covers to drain the oil. Once again fill the oil up to the fill plug.
I would use 85W90 for all these drivetrain parts.
It's unlikely but there is a chance that you have a Limited slip (maybe in the rear). This would need an additive in the oil.
If you have problems oiling the drivetrain you can start up another thread.
Nice to see this. I will get some 85w90 on my day off to change it. I wouldn'tve known what's a good oil to use. Hopefully it unlocks. Well thanx a million an hope to hear from you on my next threads. Oh an just one more quick question. Anyone know how many quarts the tranny or differencials use(estimate)?
Anyone know how many quarts the tranny or differencials use(estimate)?
You need to buy 2 gallons to do everything. Get a pump and some tubing to make it easier.

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