Help with no spark please

[conoco]

I had my truck in the garage all winter why I replaced the rockets. I pulled it out last week and it fired up right away. Took if for a drive and it ran great. Now I try to start it and it turns over really strong but has no spark.

I replaced the entire distributor
I replaced all the spark plug wires
I replaced all the spark plugs
Replaced the alternator.

I put a new ground cable from the battery to the block.

I have no idea what else to do but I am super frustrated. Can anyone help me out or give me things to check or replace that might fix it. All the other wiring works good. I just dont understand how it fired right up and drove great and now nothing. Thank u

[geezer#99]

What distributor is it?

[conoco]

It had 5 stars and people seemed to like it. Everything I researched on it said it was good too.

[geezer#99]

Do you have a dedicated 12v power supply hooked to it?
Pull the connection off the distributor and check for 12v with key on.

[57taskforce]

You can also test it by running a wire straight from the battery positive to the positive terminal of the distributor. If it starts you know you’ve got a power issue feeding the distributor. Beware you won’t be able to kill it while wired like this unless you pull the wire off the battery. You need to have 12v going to the distributor while it’s cranking and while the key is in the run position. Sounds like maybe the cranking portion of that circuit at least is not working.

[conoco]

It has power to the red and yellow wires off the distributor with my test light. Would you know what setting I need to put it on to check for volts with this multimeter?

[conoco]

I figured it put. It says I have 12.38 volts coming from the red wire I checked it at the exposed area on top

[Sheepdip]

I hate coincidences but they do happen, and seems like to me more than anyone.

Check to see if you got 12 volt power to the distributor while cranking it over.

Could be you ignition switch went south also.

[conoco]

While I am cranking it with the volt meter it goes to 0. Should it do that?

[BigBird05]

You need at least 12v while cranking it over to start. Run a test wire from the battery to the + side of the dist. (one that can be disconnected to shut off the engine ) It should start. If it does you need to find out why you don't have 12v from the ign. switch when you are cranking the truck over.

[Sheepdip]

Originally Posted by conoco

While I am cranking it with the volt meter it goes to 0. Should it do that?

Nope....your ignition switch is bad. Quick double check with a jumper wire from your battery +12 volt to your distributor +12 volt crank it over and should fire right up.

[57taskforce]

red cap racing power made me laugh for some reason. That’s your problem right there. Like I said above gotta have power cranking and in the run position.

[conoco]

It still won't fire. It does go to 10 volts with the jumper while I am cranking it though.

[57taskforce]

What’s the voltage on the battery while the key is off

[conoco]

Brand new batter read 12.35. I have dual batteries can I hook them together and try?

[conoco]

I think the last thing left to replace is the ignition cylinder. I will pick one up tomorrow. Starting to get super frustrated and disappointed. It ran so good and now nothing.

[RustyPile]

Originally Posted by conoco

It still won't fire. It does go to 10 volts with the jumper while I am cranking it though.

If you ran a jumper from the battery positive to the "BATT" terminal on the distributor and it still won't fire, The problem is NOT the ignition cylinder, NSS, starter, nor anything related to them.. The problem is inside the distributor.. With it being a new unit, don't go digging in it trying to find the problem.. Take it back and get another distributor...

I'm wondering why you replaced the alternator because of a "no run" condition??

[conoco]

[QUOTE=RustyPile;8931879]If you ran a jumper from the battery positive to the "BATT" terminal on the distributor and it still won't fire, The problem is NOT the ignition cylinder, NSS, starter, nor anything related to them.. The problem is inside the distributor.. With it being a new unit, don't go digging in it trying to find the problem.. Take it back and get another distributor...

I'm wondering why you replaced the alternator because of a "no run" I upgraded


I upgraded the alternator to a 12si 100amp about 6 months ago before I pulled it into my garage for the winter. I got the distributor off Amazon and I can return it, I just can't imagine it's faulty, its brand new. I took the cap off and turned the engine over and the distributor turned which tells me it's not mechanical. I just dont get why I can't get spark.
Test lights show power when the key is in the on position to both sides of the distributor. I checked the ohms and everything is where it should be. The fuses are good. The wires look good. The distributor I took out had the same issue,just couldn't get spark all the sudden.

[Fbks_Cruiser]

Bad ignition module in the distributor..... was the distributor you took out also HEI? If so what is the reason you swapped it? If it was, and it worked, try pulling the module from the old distributor and putting it in this one. Many parts stores can test the ignition module. I carry a spare in the glove box. I went through a very frustrating period when the engine would just stop running like turning off the key. Finally tracked it to faulty ignition module. Seems like quality control on them has gone down hill. There are many threads on the subject. I’m sure others can chime in on which seem most reliable.
If you do swap the module be sure to put real heat sink paste under it, not dielectric grease.

[conoco]

Hey cruiser it's frustrating as he'll. The very first thing I did was replace the module. I bought the last ACCEL from napa here and put it on the old distro I had hoping I would now have spark. After that didn't work I said screw it and just bought a complete new distributor which comes with the control module and everything else, I also bought to plug wires and installed the new distro and wires at the same time. Hoping that would fix it but after doing that today I still have no spark. I am going to check the ground wire from the distro to the engine, I highly doubt it will work. I pick up the ignition cylinder tomorrow and will change that out. I don't know what else I can do after that. I'm completely dumbified

[BigBird05]

Hay Conoco, I tell this to people all of the time. New doesn't mean it's any good.

[tim_mc]

I had a year-old ACDelco HEI go out on me just a few weeks ago. A new coil and module from Advance Auto Parts did the trick. I've since upgraded to Davis Unified Ignition 50K coil and their module. Runs even better now! The USA-made module from Advance is now in the glovebox as a spare.

Frankly, I'd avoid distributors with no-name labels (Yicton?) or appear to be made in China. I've read that there is a large production run of HEI distributors that are known to be defective and are being resold online.

[tim_mc]

Here is an awesome HEI troubleshooting guide I used by WIDESIDE72 on this site:
http://67-72chevytrucks.com/vboard/s...d.php?t=645976

[Luvlegs]

Any chance you went from points distributor to the electronic dizzy? Meaning you changed the resistance wire out?

[Fbks_Cruiser]

I’ve heard good things about Davis Unified (DUI). I suspect that cheap distributor has other problems too.When I change out mine I’m gonna go with a DUI distributor. Granted it cost more at $285 but worth it to not have made in China.

If your getting power to the distributor in run and start positions the ignition switch isn’t the problem. Also you said you ran a jumper wire from battery to the distributor which also eliminates the ignition switch power source as the problem.