ignition issues

hey all i just got me a 1973 jeep cj5 with a 304ci motor and manual 3 speed trans(warner t-14a left reverse?) .. a fue questions im new to jeeps ... the motor turns over and i have no spark. today i went out and got a new coil,rotor button,starter solinoid,new plugs and wires,and still no spark? the guy who had it before me put a painless wireing kit in it. and i cant much figure it out. is there a way to by pass the ignition to see if i can get a spark ? if anyone can help please let me know im ready to get this thing going out on the trails and around town

thanks,

josh

 

The stock transmission is a Borg-Warner T-15.

Use a bulb or meter and see if you have voltage at the small coil terminals with the key on.

 

And on the obscure side, make sure the distributor is turning and the drive isn't broke, don't ask me why I know this..



BUBBA

 

The way it is supposed to work is as follows:

turn the key on and 12 volts is on + side of coil.

when the points are open there should be 12 volts on - side of coil as well.

The only purpose of the points is to short the - side of the coil to ground when they are closed, and open the - side from ground when they are open.

So, with the points OPEN and after measuring 12 volts on the - side of the coil, short the - side of the coil to ground and see if you get a spark out of the coil. If so, then everything is OK up to then.

Now, suppose the points are open and there are 12 volts to the + side of the coil, but zero on the - side. That indicates one of two things, a bad coil, or the points are shorted to ground. Easy to test -- disconnect the wire from the - side of the coil and measure again. 0 volts = bad coil, 12 volts = shorted points.

If you conclude that the points are shorted, then it is likely one of two things -- condenser is shorted (unlikely, but possible) or the points were mis-installed (more likely). I suppose the wire from - side of coil to distributor could be shorted to ground from worn insulation, but I always look for the most likely things first.

If you don't even get 12 volts to the + side of the coil, then backtrack from ignition switch to battery. You'll find yourself going back through the headlight switch before getting to the battery, I'd wager.

If someone has been fooling around with the wiring harness, then it is possible that they have screwed something up.

The acid test here would be to disconnect the wire leading to + side of the coil and jumper a small wire from the battery + to the coil + and go through the above tests. If it is OK then the problem is upstream from the coil.

I ignored the obvious here -- if the points are so badly adjusted that they never close, or they are so pitted that they don't make electrical contact when closed..

 

yea it turns good and looks like its timed up pretty well. just replaced the points... and i have like 6 volts to the coil..i have that big balun resister on the positive sideof the coil... still no spark .. im stumped ....on the good side ... i have a carter afb 4 barrel carb and edlebrock torker intake... there went good gas mileage.

thanks for the replys

josh

 

Painless will ship a replacement manual, but it'll cost ya.
Did you say you replaced the ballast resistor?


gj

 

one more quick question ... found that the coil fuse has been blown ... i cant get anything on a purple and whire wire going to the coil .. anyone know what the fuse rateing is for that i just put in a 30 amp for a test and it blew ... thanks

josh

 

yea i replaced that resistor they told me to put it in the positive side of the coil


josh

 

ok well .. that resistor started smokeing ... i dont think that should be normal ... i checked the wireing the positive side of the coil is going to positive.. the negitive side of the coil gos into the distribuiter to the condencer and the orange wire from the condenser is going to the points..i ckecked the ground when the points are open its open and when the points are closed ground is connected ... if anyone lives in missouri and knows these things better than i do ... and can fix it ... i can pay ... lol ...

anyone have any more ideas ... im about out ..

josh

 

Shorted condensor? Points mounting screw too long? (shorting to the distributor body)

Do you have a meter (DVM)?

Disconnect the wire (not the spark plug cable; the wire) from the coil to the distributor and measure its resistance to ground. Should be infinite (open) if the points are open, and climb from low to infinite if the points are closed (as you charge the condensor with your meter).

 

just got back from the store ... got a new condensor ... im gonna go put it on real quick and see if that helps anything ... heres hope'n

josh

 

still no spark ... sigh

 

Do you have a meter (DVM)?

 

yea i got one not the best one in the world i keep it in a car kit iv been useing it alot these past fue days ..

josh

 

Back to the basics.

You gotta have 12 volts on the + side of the coil. If you only have 6 you don't have a working ignition.

So, why not put the above statement to the test. disconnect the + wire(s) from the coil. Jumper a wire from battery to + side of coil and crank.

If when cranking you don't get a spark (from the high voltage output of the coil) you have a downstream problem. If you get a spark you have an upstream problem.

If you get a monster spark from your test wire when you connect it to the + side of the coil the coil is internally shorted and should be replaced.
BTW, that could explain all your problems...

From the sounds of it (ballast resistor smoking) you have an upstream problem anyway, but with this test you can troubleshoot the ignition system from the coil to the plugs and fix the no spark problem -- then you can go back and fix the short problem.

Now, you may have people tell you that you have to have the ballast resistor and shouldn't put 12 volts on the coil. That is not correct. The coil will operate with 12 volts on it and no ballast resistor. In fact, the solenoid that is supposed to be in the jeep has an extra terminal on it (labelled I) that shorts around the resistor wire and puts 12 volts on the coil when starting.

That could be another place to look for your short by the way. If you don't have the solenoid that has the extra terminal on it, or it is not connected, it is possible that the wire that should be connected to it is touching ground somewheres. I don't know what painless wiring did for that circuit, but the factory circuit called for a green 14 gauge wire that went from + side of coil to the extra terminal on the solenoid. That is in addition to the resistor wire which goes elsewhere -- to the ignition switch.

The system does call for a resistor wire going from the ignition switch to to the coil when running, but for testing purposes you can take it out of the picture to prove the downstream.




A blown fuse indicates a short. Now it may have been a temporary short like someone grounding the voltage with a screwdriver, or it may be a permanent short.

It is normally easy to find a short. Find the blown fuse - the short is after that. Find what is smoking. The short is the thing smoking or it is after that. Usually the short is directly associated with whatever is smoking, but not always.

The wiring diagram for a 73 cj does not show a ballast resistor. It does show a resistor wire from a firewall connector to the coil.

I'm not sure what the resistor wire that manual calls for in the circuit is for - it may be a fusible link, or it may actually be a resistor to drop voltage. I suspect that it was a combination of both since the solenoid shorts around it when starting, and if there was no voltage drop across it then there would be no reason to short around it during starting. Since there is no fuse called out in that circuit this wire could double as a fusible link.

I haven't the foggiest idea where you would get this resistor wire, but Painless ought to know...(heroic assumption)

Lastly, since you are working with something that smokes and could burn and there is gasoline nearby, you should be working outside with a fire extinguisher. Not water!!

 

yea im thinking its downstream, im getting no spark but i am getting voltage to the coil .. ill try takeing that resistor off .. it stoped smokeing it seems they put some kinda oil on it to keep the wires in good shape for storage ?im getting 9 volts at the coil and no output and they told me the resistor gos on the positive side .. i dont know if that is correct .i have a green and a red wire going to the postive side the red wire looks like its comeing from the fire wall and the green is comeing from the I side of the coil also there is a mystery purple with white stripe wire, the negitive side of the coil is going to the capisitor in the rotor and the orange lead of the capisator is going to the points and on the vacume advance module there is a black ground wire that gos to the ground.. i checked all the points for proper connection and no shorting .. i checked all the fuzes.. all good there now .. on the bottom of the fuze block on this painless kit there is a black square relay .. does that have anything to do with it .. also does the altinator have anything to do with it ? its a pretty easy looking wireing job ... yet im just plum confuzed ... on to a new problem... i know the clutch works .. because i put it in gear and hit the started and it moved forward and backward .. but the clutch petal is slinky and loose it looks like all the adjustment rods are about adjusted as far as they can go ... maybe the fork is broken or the throwout bareing is wacked up ? so i need to take off the trans as well and see what the deal with that is ...

on the good side the soft top looks in good shape .. the doors fit .. but i guess im missing the metal bar that go's into the soft top to hold the soft doors closed good .. the fact that i have no tail gate is ok with me there is just a nice piece of diamond plate on there with the snaps on it for the top it does have a full roll cage and it has no signs on any fluid leakage not even a drop of oil so the motor is in good shape its just this spark'n thing .. i wish there was someone here in mid missouri that was on this web site who could come by and take a look at it for me .. im no expert on ignitions ...

thanks everyone for all the help with this is a really wonderfull place with good info
oh and i got a huge all rates extinguisher that i got whyle i was a fireman .. it will stay with the jeep

josh

 

Josh, try this site http://abbysenior.com/mechanics/ignition.htm
It even has a video of the various parts.

You should be able to get a spark by manually opening and closing the points, using something well insulated like a screwdriver or (better) a popsicle stick. If you have 9-12 volts between ground and where the ballast resistor connects to the coil, and the condensor and points are new, you should see a spark. Hold the coil wire 1/4" away from the engine block (with something well insulated!), turn the key on, and open and close the points. If you don't see a spark, then it's likely your coil is defective.

You have to be sure that your points and condensor are installed correctly. There also should be a ground wire from the distributor body to the points mounting plate. The condensor wire and distributor lead (fron the coil to the points) must also be installed correctly and in good condition.

With the points open and key on, you should have 12V going into the ballast resistor, coming out of the resistor, going into the coil (small terminal), coming out of the coil (small terminal), and at the points contact that connects to the distributor lead (from the coil). The other points contact must have zero resistance to ground.

With the points closed and the key on, you should have 12V going into the ballast resistor, about 9V coming out of the ballast resistor and going into the coil, and close to zero volts coming out of the coil.

 

If you go through all of timgr's advice and eliminate all possible mechanical shorts, but are blowing 30 amp fuses to your Coil+, remove any amp/volt gage wires (including the combo fuel/amp if applicable.
Start with a fresh Coil+ wire right from your fuse box or temporarily from a fused battery connection. You sound like you have a dead short somewhere. That "oil" inside your ballast resistor is probably PCB's, don't breath any smoke coming from it & avoid contact with it.. The resistor sounds smoked also. My ballast resistor for my 232 is mounted on the right firewall, like the previously mentioned diagram. It may be worth a try to isolate the resistor to such a place.
Good luck.

gj

ps: here is an odd afterthought, but if you are running a cheap dash ignition switch, or even running a column switch (especially w/tilt wheel), I've seen the ignition switches get a little old & loose and cross-over juice to incorrect wires. Tilt wheel harnesses can break like flat wire tech and short across a metal contact.

 

body,trans,axle, stuff

thanks for all the help ... ill get back on it after a whyle i decided it was giveing me a migrane so i decided to work on something else on the jeep ... a fue questions i dont know if i should post them on here or another new thread but umm it does not have a tilt wheel... it has an indash ignition switch... umm it seems i have a 3 speed transmission i dont know what kinda it is maybe someone can help and tell me what ones of a 3 speed they put in a 73 cj5 with a 304... also it has hub locks on the frount axle .. they seem like they are hard to turn is that normal? also the transfer case .. it has the shift lever that looks like a flat bar and only moves forward and backwards the linkage is broken so ill have to weld it up ... do you know if it is all time 4 wheels drive or not ... all the shifter knob says is hi-lo .. but i think it may be an aftermarket knob.. im hopeing it has a N posision so it wont suck up too much gas ... the other thing is that .. the seats go back as fat as they can go and hit whe back wheel well and for me that still aint far enuff back im a big guy so if there any mods for that so i can get more leg room .. the seats are bolted to a big metal plate with hindges what moves up and a storage place is under each seat so it looks like i will have to keep a lock on the lid to keep the seat from flipping in the event of a roll over or an accident .. does anyone else have a setup like that ?

 

Hard-turning locking hubs are not normal. Locking hubs indicate that you don't have full-time 4WD.Your standard transfer case from firewall back is 4H, N, & 4L. You may find a 2L twixt N & 4L. They put them in the transfer cases for a few years, but the transfer case kept jumping out, so they just took the 2L position off the transfer case shift knob. If it does stay in 2 L, hang onto that transfer case. I had one & it was awesome, but had to part with it.
If you can find a way to lower your seat, it will give you more room. My '74 set up is a tubular front mount & can be lowered.

gj

revised - on my '74 manual trans. it's from firewall - 4H, 2H, N, 4L (with that possible 2L twixt N & 4L). you normally drive on the road in 2H & the hubs unlocked. Somebody sells a kit for the transfer case to allow a reliable 2L now.