Ignition Issues...Need Help!!

So I've been reading the archives over the last few days and cannot figure out what is going on with the Jeep. Its a 74 CJ5, 258 6 cyl, 3-speed, points iginaition, most if not all stock and ran excellent until this last weekend. It should be noted that I just replaced the timing chain and cover gasket. After the timing work, I took it for a drive down to the beach (20 min each way) on mother's day with the wife and kids and she ran great. Got home, fired it back up and ran a few local errands. Well, I came to a stop light and she puttered out as I was taking off, but fired back up in the intersection. Then about a half mile later, I came to a stop sign and she puttered out again, but wouldn't start back up and when I tried starting a few times, it let out one hell of a backfire POW!!! like an M-80 went off out of the pipe. Since then, I haven't been able to get it started again. Here are the facts/symptoms:

1. Initially tried some starter fluid in the carb. After about 10 tries I got it to fire for a second, but it quickly died out and that was the last time it ran. Now, I turn the key and the starter will engage and turn the engine but it won't fire up. The fuel filter is full (looks too full to me as it is one of the see through plastic ones and is almost bulging with pressure) but the carb seems to spray correctly when gas is applied.

2. I pulled the plugs and they looked ok, cleaned them up and reinstalled.

3. Pulled the dist cap and cheked the points and for any signs of extreme burning, but all looked ok.

4. Swapped in a new coil, but getting no spark if I pull the wire from the coil to the dist and touch to the block while cranking. Tried replacing that wire as well

5. Replaced a portion of the green wire (stock harness) that goes from "I" post on solenoid to the + coil terminal as it looked damaged. There is also a red wire that goes to the + on the coil (is this the "resister wire" referenced in the manuals?) that looks old but not broken.

6. Then tried using a jump wire from "I" terminal on solenoid directly to positive on coil, still no spark.

I'm running out of ideas and would really appreciate any thoughts.:?

Last thing to note is that prior to this issue and prior to the timing chain replacement, the same type of thing would happen when the engine would heat up real good (i.e, the jeep would sputter when giving it gas coming from a stop), but otherwise ran great and reliably.

Nice weekend coming up and would love to get it moving again.

Thanks in advance.

Nick

 

Hum maybe a worn distributor or cam gear...try to start the engine with the cap off and see if you have rotation on the rotor

 

I'll give it a whirl, but I don't think that is it as there is no spark coming from (or into, for all I know) the coil. Is there any way to see if there is spark going into the coil? I tried the direct jump from the "I" post to the + on the coil and nothing changed.

 

Maybe your timing chain jumped, causing timing to be off, causing the backfire and no more ignition.

You might want to try getting #1 piston to TDC and see where the timing mark is as compared to where you set the timing. Also check if the distributor itself is bolted down tightly, it could have moved a bit, also causing your timing to be off.

I think you can take off the coil wire that attached to the spark plug cap and see if you are getting spark past the coil. But you need some additional expert advice on how to do that since I believe the voltage is pretty high at that point. That would at least tell you that the coil is good.

 

Your problem is no spark.

You should have 12V at the (+) terminal of the coil with the key on ... maybe you have a bad ignition switch?

Realize that you should be able to make spark at the coil wire by momentarily grounding and un-grounding the coil primary (the 12V and ground connections). Unplug the big wire from the coil to the distributor and lay it on the engine block. Disconnect the distributor from the points wire and ground/unground the (-) connection of the coil with a piece of wire to make a spark from the coil wire next to the block. Keep your other hand in your pocket, don't go barefoot, and don't lean on the Jeep. It should be safe to ground/unground the primary of the coil, but if you ground yourself to the Jeep or earth, you may feel a tingle.

 

I replaced the ignition switch less than a year ago. Could it have gone that quickly? I will try the tests you suggested when I get a chance later tonight. Could the solenoid be bad even though it is getting juice to the starter when I turn the key?

 

When there's no start, you always check for two things first - spark and gas. You need spark. No spark, no start. Turn on the key and check that you have 12V to the coil. Check that the coil makes spark. THEN check that you have 12V to the coil when you are cranking.

 

Try a other set of points and condenser is new . Points are cheap are eazy to change.

 

My 75 died for no reason last year.. No spark etc, I replaced the ignition module and it came back to life. A lil research revealed that the crappy Prestolite ignition is very un-reliable..

 

same issue with my '75. changed out the prestolite BID unit for a 6-cyl chevy HEI unit (perhaps a 4.3L) that i got via a junkyard, and used an HEI cap from an buick/oldsmobile 6-cyl. second best modification i've done to the jeep. no more random engine cutouts, hard starts, jerky operation. idles excellently. i recommend the conversion. the pertronix conversion is supposed to be good, too, but i have no experience with it.

wally

 

Your just fartin in a wind storm until you do as Tim advises about ignition voltage. That red or pink wire going to the + term of the coil requires battery voltage with the key "ON". That power wire to the coil will be a fat red or pink special resistant wire that takes the place of the old ballast resistor used on early models. So turn the key on and check the + coil term for power. No power then follow that resistor wire back toward the firewall where you will find a six wire connector that goes inside to the main harness. Unplug this connector and test the prong/socket for the red wire for power on the main harness side. If you have power there, then you are loosing it at that plug. If you don't have power at that point then you will have to check that red wire where it comes from the ignition switch.

P.S. That resistor wire can burn in two inside that special coating and the way you check it is to pull on the wire from each end and if it streatches like a rubber band then you know the resistive wire has burned in two.

 

ditch the points and do hei or pertronix

 

I'm going to check power to the coil shortly. The info on the resister wire is very helpful. Thanks to all for the help. I'll keep you posted.

 

Ok. I ran the tests Tim suggested and I got no spark. So I changed the solenoid, points, condenser and a potrion of the green wire running from the solenoid to the + coil that appeared worn, charged the battery, shot some started fluid down the carb and she fired up. Now just need to reset the timing cause she runs like crap...Thanks for the help.

Nick