Problem came back all the sudden

[conoco]

About 2 months ago I posted about how I didn't have and spark. That post tons of people chimed in and I ended up getting my truck to start back up. During that time I have taken my truck on 2 fishing trips and about 900 miles total. My truck has ran flawless. Starts first turn, when it sit over night out side she fires right up.Power is great and most that driving has been at highway speeds. I was just driving to an appt hit the highway for about 15miles and all the sudden truck started to sputter and then die. I gave it a couple minutes and it started right back up. Drove about a quarter mile and it did it again. Now it Wil not start at all and I have no spark. Anyone have a clue or anything I can trouble shoot? I am beyond frustrated. Thanks for any help again.
What I replaced after my first post
New distributor with coil
Spark plug wires
Spark plugs
Ignition switch

What I have done so far
-Test light shows power to the batter wire of the coil with the key in the run position
-put a jumper cable on the positive battery post to the batt wire on the coil and nothing happens
-tested fuel pump and it is 5.5psi and good.
Fuel filter is clean and gas shoots in the carb when I engage the throttle.

[pjmoreland]

If you've got good voltage at the battery wire of the coil, and you still don't have spark, then there's got to be something going on with your distributor. I see you've replaced it recently, but there could still be something wrong with the new one. It could also be a grounding issue. Does it make any difference if you connect a wire from the negative terminal of your battery to the metal housing of your distributor?

[conoco]

Originally Posted by pjmoreland

If you've got good voltage at the battery wire of the coil, and you still don't have spark, then there's got to be something going on with your distributor. I see you've replaced it recently, but there could still be something wrong with the new one. It could also be a grounding issue. Does it make any difference if you connect a wire from the negative terminal of your battery to the metal housing of your distributor?

I didn't try that and will let you know. I used a multimeter and took the coil out to test for ohms. Everything tested with in specs.

It is a brand new distributor and everything had ran so solid up until now. Frustrating. I'll let you know. Thank u

[Willys_MB]

I recently had a similar issue. My situation was different because I have an HEI; however, I thought it was worth chiming in. I see you replaced the distributor. Mine was so worn that the physical specs on it (end play, for example) were out of whack. It’s not unheard of to get a new part that is out of spec or just plain poor quality. Maybe give the dizzy/coil a once over and check all your grounds. Was the dizzy clamped down tight? Could your timing have gotten messed up?

I’m just throwing everything out I can think of. It wouldn’t be unheard of to have a new issue pop up that’s causing the same symptoms, either.

It doesn’t sound like it, but could it have been vapor lock? Distributor issues can mimic the symptoms of vapor lock. Check the voltage at the coil. The test light might tell you there’s voltage, but maybe it’s too low?

[conoco]

Originally Posted by Willys_MB

I recently had a similar issue. My situation was different because I have an HEI; however, I thought it was worth chiming in. I see you replaced the distributor. Mine was so worn that the physical specs on it (end play, for example) were out of whack. It’s not unheard of to get a new part that is out of spec or just plain poor quality. Maybe give the dizzy/coil a once over and check all your grounds. Was the dizzy clamped down tight? Could your timing have gotten messed up?

I’m just throwing everything out I can think of. It wouldn’t be unheard of to have a new issue pop up that’s causing the same symptoms, either.

It doesn’t sound like it, but could it have been vapor lock? Distributor issues can mimic the symptoms of vapor lock. Check the voltage at the coil. The test light might tell you there’s voltage, but maybe it’s too low?

I'll check the voltage. Hopefully it's still at 12 or 10 volts with the engine turning over. My timing is good. I put it at top dead center and balancer is on 0 also. Same position as when I replaced everything. It ran great the last 800 miles so don't know what else it could be.

[54blackhornet]

Timing should be before TDC ?

[BigBird05]

You need a test spark plug. Pull the spark plug wire off of a plug and see if there is any spark and what color it is.

[conoco]

Originally Posted by BigBird05

You need a test spark plug. Pull the spark plug wire off of a plug and see if there is any spark and what color it is.

Spark plugs all look good, they have 800 miles on then since I changed them. I pulled the #1 plug and put it on a spark plug tester and got no spark. I then checked #'s 3,2 and 6 plugs and also had no spark.

I also pulled the coil wire and held it about 1/8 inch away and didn't have any spark either. But I do have power to the batt terminal on the distro through out all this.

I am pulling my headers and valve covers so I can get to the engine harness. Time to unwrap the tape and start checking the wires. I just can't think of anything else. Maybe the ignition control module but if all this fails I guess I will buy a new one even though the distributor is new and came with one 🤔.

I'll keep plugging away.

[conoco]

[QUOTE=54blackhornet;8951341]Timing should be before TDC

I'll try that. I have kept advancing it by 2 trying to get it to start. It was only at 0 because I took the distributor out. Put number 1 to TDC and left it on zero. Since I couldn't start the truck I couldn't get the timing light on it. I will advance it a little more see if that helps.

On a side note even if it was below or advanced wouldn't it still have spark regardless?

[pjmoreland]

I have a vague recollection of reading about someone who had a no-spark situation that was caused by their tach. They unplugged the tach from the HEI and then the engine would start. It's an easy thing to test.

[conoco]

I replaced the distribution with a new hei. The one I replaced was also hei. The onlything I didnt replace was the ignition module, but that's because the new distro came with one. Just sucks and really frustrating. Everything that has been running great since I thought I fixed this problem last time. There has to be something I am missing.

I will unplug the tach and see if that hailmarry works. . Thanks for the help so far guys.

[Willys_MB]

Originally Posted by conoco

I replaced the distribution with a new hei. The one I replaced was also hei. The onlything I didnt replace was the ignition module, but that's because the new distro came with one. Just sucks and really frustrating. Everything that has been running great since I thought I fixed this problem last time. There has to be something I am missing.

I will unplug the tach and see if that hailmarry works. . Thanks for the help so far guys.

HEI's are very sensitive. There needs to be a relay in place to ensure that it's getting the proper 12 V when it's on. Perhaps there is no relay and the voltage is dropping too low due to a 50+ year old connection somewhere?

[burnin oil]

Originally Posted by Willys_MB

HEI's are very sensitive. There needs to be a relay in place to ensure that it's getting the proper 12 V when it's on. Perhaps there is no relay and the voltage is dropping too low due to a 50+ year old connection somewhere?

No need for a relay. Clean the contact points and it will be fine.



Another poster talked about the starter lead. In addition make sure the ballast resistor wire is removed to ensure a full 12v to the dizzy.

[burnin oil]

If you direct wired the dizzy from the battery and it still had no spark then its not the truck wiring.

Pull the cap off the dizzy and check the little black button for burn marks or melting. If the ohms are not correct it can cause a coil failure. I ran into this with an MSD ignition but it could happen with a cheap cap also. Another thing to check is that the center of the rotor button is lifted some and contacting the black button. I have bent a couple to get a good contact in the past.

Double check that you have a good ground connection from the engine to the battery. A set of jumper cables from the alternator bracket to the battery negative is a quick test.

Most part stores should be able to check the ignition module or just install a new name brand one.

I recently had a coil failure, not HEI. That ran and drove just fine. I noticed it smoked like crazy at idle and had me chasing my tail thinking it was a carb issue. Previous coil that I replaced would cut out on long drives. Say 30 minutes or longer than work again once it cooled off. Problem got worse as the windings broke down.

One last thought is a bad or extremely rusty reluctor wheel. Its the star gear looking thing at the very bottom of the dizzy on the inside. I have seen those fail buy light surface rust was never an issue.

[BigBird05]

If the starter is working you have a good ground. If you have 12v to the dist while cranking then the problem is in the dist. If you have a friend that has a known good dist borrow it from him.

[tim_mc]

I believe your new distributor is a Yicton brand (Chinese?) bought on Amazon. I'd recommend a GM HEI, but mine lasted only a year before I had to replace the coil and module (now using a DUI coil and module on the GM unit with great results). I suspect you got a cheap distributor. An OEM GM HEI would be best IMO, even if it needed a coil and module.

[Grumpy old man]

Maybe I'm missing something here but why are you chasing timing and wiring gremlins ? You just put a new hei in it and it was running good and then stalled ? You have power to the dist ? but no spark to the plugs ? If it was mine I'd toss a module in it using good Thermal paste not dielectric grease and I'd be willing to bet that solves the problem , If this happened to me on the side of the road I would hit the closest auto parts store and grab a module and coil drop the module in first and try it if no start drop the coil in . I keep a spare module in the glove box and I'm using Protronix Series 9 Extreme Performance Thermal Compound Paste that comes in little syringes .


" I was just driving to an appt hit the highway for about 15miles and all the sudden truck started to sputter and then die. I gave it a couple minutes and it started right back up. Drove about a quarter mile and it did it again. Now it Wil not start at all and I have no spark "

This is probably when the module was over heating and finally cooked it's self .

https://www.amazon.com/dp/B07PQTT3WZ...jaz10cnVl&th=1

[tim_mc]

Originally Posted by Grumpy old man

" I was just driving to an appt hit the highway for about 15miles and all the sudden truck started to sputter and then die. I gave it a couple minutes and it started right back up. Drove about a quarter mile and it did it again. Now it Wil not start at all and I have no spark "

This is probably when the module was over heating and finally cooked it's self .

That's exactly what happened to mine - would warm up, sputter, cough & die. A few minutes cooling down would get it started again. Got it home and after redoing the intake I didn't get any spark. New module and coil fixed me up: https://67-72chevytrucks.com/vboard/...d.php?t=822473

Here's the pertinent stuff from my thread:
5/30/21: Tried to start truck. Crank, crank...nothing. Had wife crank while I checked for spark on #1 to the header with a screwdriver. Didn't see a spark and was too chicken to grab it by hand. After church, got a Harbor Freight 90° In-Line Spark Checker ($3.99 - smokin' deal), Advance Auto Parts/Carquest HEI ignition coil EBC1483, and 4-prong HEI module CBE1004 (Made in USA!). Installed module and coil. Fired up and ran great with good light on the spark checker. Took for short drive and it died instantly, seemed electrical in nature. Let it sit for a few minutes, fired it up and drove it home. Truck died again on a short drive, so I disconnected the tack lead, which is also wired to a kill switch. Truck died unexpectedly again. Reconnected tach lead since it wasn't the problem. Let it cool, fired up and made it home. Drove it a few times later that day with no issues. Starts and idles OK. No problem with idle dropping at stop lights in gear. Concerned that the new module may be flaky.

5/31/21: Ordered a Davis Unified Ignition DUI-240001BK 50KV cap/coil kit and DUI-000222 module from Summit. (Edit: Reviews of the DUI parts were mostly excellent with claims of improved starts, power and idle. According to DUI, their Dyna-Modules have more electronic dwell than a stock module, so the coil saturates longer and produces a more intense spark. I figured while I was at it I'd bump up the coil output with the DUI cap & coil kit that includes a burn-through resistant brass terminal rotor.)

6/3/21: Distributor upgrade kit and module arrived and installed. Fired up.
WOW. I thought buying a stock GM HEI would be adequate, but this was a great upgrade. Truck starts super fast, idles great, and seems to have a cleaner exhaust.

I now keep a spare module in the glove box too.

[57taskforce]

Originally Posted by Grumpy old man

Maybe I'm missing something here but why are you chasing timing and wiring gremlins ? You just put a new hei in it and it was running good and then stalled ? You have power to the dist ? but no spark to the plugs ? If it was mine I'd toss a module in it using good Thermal paste not dielectric grease and I'd be willing to bet that solves the problem , If this happened to me on the side of the road I would hit the closest auto parts store and grab a module and coil drop the module in first and try it if no start drop the coil in . I keep a spare module in the glove box and I'm using Protronix Series 9 Extreme Performance Thermal Compound Paste that comes in little syringes .


" I was just driving to an appt hit the highway for about 15miles and all the sudden truck started to sputter and then die. I gave it a couple minutes and it started right back up. Drove about a quarter mile and it did it again. Now it Wil not start at all and I have no spark "

This is probably when the module was over heating and finally cooked it's self .

https://www.amazon.com/dp/B07PQTT3WZ...jaz10cnVl&th=1

Beat me too it but I agree; it’s cheap and the first thing I’d swap.

[RichardJ]

Your starter solenoid has two small terminal posts. The "S" terminal is for the starter Circuit from the Ign switch. The other terminal is marked with an "R" or possibly "I" and should be used ONLY with the Points Ign Distributor.

If you still have a wire connection on the "R" terminal, remove it and replace the module.

The "R" terminal has a little finger that can get bent and repositioned incorrectly. If the the solenoid disc flops around and makes contact with the "R" finger, it can send a 400V EMF into the HEI, frying the module. I'm talking about when the solenoid is released and the disc is pulling back.

When the solenoid is energized, it generates a large magnetic field. When the magnetic field collapses, it generates a huge voltage spike that goes unnoticed with a points distributor.