no spark and out of ideas

[Kiowa Flier]

I'm asking for help from the knowledgeable folks on this forum. My issues started about a year ago while driving. My jeep (1959 CJ5 , F134 Hurricane engine) started losing power while driving and soon just died. It acted like the fuel pump had quit, so I replaced that...it ran a little but quickly died again. During further attempts, the engine ran shorter and shorter, and eventually I couldn't get it to start at all. It was especially bad after warming up. Looking back, I did a very poor job of troubleshooting at the time. In the end, I replaced the coil, the points/cap/condenser, the fuel pump, the spark plugs and wires, and even decided to upgrade my Solex carb to a rebuilt Carter YF. Still nothing. Finally did a vacuum test, which suggested a valve issue. Since I had no idea how old the engine was since a rebuild, I decided to have it torn down and re-built. 6 months later, I got my engine back from the shop, and of course...still can't get it to start. So, I'm attempting to stick with methodical troubleshooting now. To that end, I followed closely the "engine won't start" thread in the technical forum. I put my Solex carb back on the engine since I believe it was actually functioning normally a year ago. It squirts gas down the throat when I pump the accelerator and the fuel system seems to be functioning normally. I believe my issue to be electrical. Here is what I've done so far:
1. New Omix Ada electronic distributor from KW (I accidentally destroyed the points in my old distributor and decided rather than buy more points, I'd just upgrade the distributor.
2. New Pertronix 3.0ohm Flamethrower coil - internal resistor.
-primary resistance is at 3.4 ohms, which seems a bit high according to
multiple sources, but it is a brand new coil. Can't remember the numbers,
but I'm 99% sure the resistance was less than that a week ago when I
bought it. I have an older coil which I removed last year while
troubleshooting, and its resistance is closer to 6.
-secondary resistance is at 10,000 ohms.
3. Resistance on plug wires is between 5800-7900, and plugs are gapped to .03. Resistance on coil-distributor cable is 2800 ohms.
4. With key on, I've got 12v on positive and negative terminals of the coil.
5. I unplugged the distributor-end of the coil-distributor cable, and checked with multimeter while cranking the engine. It was 8 volts.
6. I tried holding that cable near/on a ground, and got no spark. Weird thing is that yesterday I did the same thing, and got sparks. An hour later after attempts to start in vain, I checked it again and nothing. Same story with the spark plugs.

Feels like I'm out of things to check now, but something's obviously not right. Sure appreciate any ideas you all may have. Apologies for the long post but I wanted to include everything I've done.

 

[Torxhead]

There might be a poor electrical connection in there somewhere. I am thinking due to wear or corrosion, starting from the ignition switch and tracing the system down. A wiring diagram could help if you do not have one:https://colorwiringdiagrams.com/

 

[bzahler]

Make sure you have Power to the coil while cranking

 

[mriplaybass]

Are you using a 12V coil? If you are still using an original F head coil, they may have been 6V, at least that is what our 54 3B is. Unless you did a 12V conversion using a resistor between the battery and the coil, running 12V into a 6V coil will not let it live very long.

 

[Kiowa Flier]

Make sure you have Power to the coil while cranking

I've got a steady, continuous 8.7 volts on both the + and - terminals on the coil. Should it be a full 12 volts?

My system is a 12 volt system. Not sure if it was originally that way, but it's been 12 volts since I bought it 6 years ago. I confirmed the coil is for 12 volts.

 

[Kiowa Flier]

The only parts of the electrical system I haven't replaced are the generator, voltage regulator, and ignition. I assume the generator doesn't have any effect on the start sequence; what role does the voltage regulator play? Could it be affecting voltage to the coil? My ignition seems to be okay, since I do get 12 volts to the coil while the key is in the "on" position.

 

[Captainlance]

I read your post a few times. When you say you put the distributor-coil lead to ground and cranked the motor, you go no spark. Are you referring to the high tension lead? or the small , thin wire ? If you are referring to the thick (high tension) wire, and cranking the motor, you should get spark as the distributor turns. When you say that you get 12v. on BOTH sides of the coil, is this with the dist. turning?
If so, your distributor is probably the trouble, the voltage must go to ground each time the points (or reluctor) in the case of an electronic dist. passes a cylinder firing point.
Also, I assume that you verified that the dist. is in fact turning when he motor cranks, and that it is oriented correctly, and not 180* out.

I'm asking for help from the knowledgeable folks on this forum. My issues started about a year ago while driving. My jeep (1959 CJ5 , F134 Hurricane engine) started losing power while driving and soon just died. It acted like the fuel pump had quit, so I replaced that...it ran a little but quickly died again. During further attempts, the engine ran shorter and shorter, and eventually I couldn't get it to start at all. It was especially bad after warming up. Looking back, I did a very poor job of troubleshooting at the time. In the end, I replaced the coil, the points/cap/condenser, the fuel pump, the spark plugs and wires, and even decided to upgrade my Solex carb to a rebuilt Carter YF. Still nothing. Finally did a vacuum test, which suggested a valve issue. Since I had no idea how old the engine was since a rebuild, I decided to have it torn down and re-built. 6 months later, I got my engine back from the shop, and of course...still can't get it to start. So, I'm attempting to stick with methodical troubleshooting now. To that end, I followed closely the "engine won't start" thread in the technical forum. I put my Solex carb back on the engine since I believe it was actually functioning normally a year ago. It squirts gas down the throat when I pump the accelerator and the fuel system seems to be functioning normally. I believe my issue to be electrical. Here is what I've done so far:
1. New Omix Ada electronic distributor from KW (I accidentally destroyed the points in my old distributor and decided rather than buy more points, I'd just upgrade the distributor.
2. New Pertronix 3.0ohm Flamethrower coil - internal resistor.
-primary resistance is at 3.4 ohms, which seems a bit high according to
multiple sources, but it is a brand new coil. Can't remember the numbers,
but I'm 99% sure the resistance was less than that a week ago when I
bought it. I have an older coil which I removed last year while
troubleshooting, and its resistance is closer to 6.
-secondary resistance is at 10,000 ohms.
3. Resistance on plug wires is between 5800-7900, and plugs are gapped to .03. Resistance on coil-distributor cable is 2800 ohms.
4. With key on, I've got 12v on positive and negative terminals of the coil.
5. I unplugged the distributor-end of the coil-distributor cable, and checked with multimeter while cranking the engine. It was 8 volts.
6. I tried holding that cable near/on a ground, and got no spark. Weird thing is that yesterday I did the same thing, and got sparks. An hour later after attempts to start in vain, I checked it again and nothing. Same story with the spark plugs.

Feels like I'm out of things to check now, but something's obviously not right. Sure appreciate any ideas you all may have. Apologies for the long post but I wanted to include everything I've done.

 

[Lumpy Grits]

Run a jumper wire from the POS(+)side of the battery, to the POS(+)side of the coil.
Will it start now?
If no start-My bet, the dizzy is at fault here.
LG

 

[Kiowa Flier]

I read your post a few times. When you say you put the distributor-coil lead to ground and cranked the motor, you go no spark. Are you referring to the high tension lead? or the small , thin wire ? If you are referring to the thick (high tension) wire, and cranking the motor, you should get spark as the distributor turns. When you say that you get 12v. on BOTH sides of the coil, is this with the dist. turning?
If so, your distributor is probably the trouble, the voltage must go to ground each time the points (or reluctor) in the case of an electronic dist. passes a cylinder firing point.
Also, I assume that you verified that the dist. is in fact turning when he motor cranks, and that it is oriented correctly, and not 180* out.

Sorry, yes, the high-tension lead...no spark. I re-verified 12v from both sides of the coil even while cranking. No fluctuations at all, and the rotor was turning. Sounds like the distributor is faulty; fortunately I'm able to return this distributor for a full refund, so it's packaged up and I'll probably just get a replacement set of points for the old distributor. I sure am learning a lot but it can be a frustrating process. Thank you all for the help!

 

[Captainlance]

OK, easy way to check, take the wire from the NEG side of the coil and touch it to the ground quickly, the spark should happen at the high tension lead to the dist. If so, the dist. is bad.
if you need more help, feel free to call me any evening, 516 935 6249
Lance

 

[Kiowa Flier]

So, I ended up sending the Omix-Ada electronic distributor back. Instead, I ordered a Pertronix electronic conversion kit, part # 1548. My distributor is an IAY 4012, which Pertronix doesn't make a kit for. However, the 1548 looked like it should fit, and sure enough, it dropped right into place. I put it in today and the jeep fired right up! I'm surely not the first one who has put a Pertronix 1548 in an IAY 4012, but I couldn't find a write-up anywhere on it. So here it is...it works really well. Can't speak for longevity, but it sure was easy to install.

 

[Torxhead]

Thanks for the update and glad you got it to work.

 

[mtnwhlr]

So, I ended up sending the Omix-Ada electronic distributor back.

All they sell is .

 

[Belizean]

Wait until they buy out Fiat/Jeep !

 

[slomo]

You still need to verify you have 12 volts at cranking. 8.5 volts is rather low.

And don't stop there, improve the grounds ALL over the Jeep. Use some 1/0 copper battery cable and copper connector lugs. Go from the alternator case rear, to the battery - post. Battery - post to the starter mounting bolt. Battery - to the tub.

Depending on your ignition setup, a relay for full battery cranking voltage is a great idea. Soon as I turn the key to crank she fires off immediately.

A fused, heavier + wire from alternator to battery will make the alternator operate at full specs and reduce heat buildup.

Glad to hear you got it running.

slomo