When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Sorry in advance to drag you in to the abyss that is my life but I really appreciate any help passed on to me. Recently I started work on my 75, and I will be dammed if I can't get the thing started or to even spark. I know I am not getting spark, got an in line spark plug checker and nothing sparking. NEW battery, cap, rotor, wires, plugs, coil and contol module. All that and no spark. Is there some sort of safety or link that I am not accouting for that would let it crank but not spark. Fuel is not the question now once I get a spark and it is not starting then I will cross that bridge. Thank to anyone who can help in anyway possible.
Forgot to mention: * Auto trans * has HEI * hasn't run for God knows how long * mostly original *Also extremely good point; I definitely don't fully trust new parts.
Start with a good description of your car and engine.
Stock HEI?
Manual/Auto?
Modified or stock?
Have you or anyone changed any electrical parts since it last ran?
Have you checked for 12v at the BAT terminal on the HEI cap?
Good place to start is your ground wires. Make sure the connection points are all clean and tight.
Also, just because you installed a new Chineseium electrical part does not mean it works!!
I believe all the safety (start) switches such as neutral, clutch depressed, etc would not allow a crank mode. You have crank / no start mode.
You changed the coil. Did you find and connect a black small gauge wire to one corner of the coil frame?
(Some years did not have a wire but a GRD bracket instead) Regardless, the coil has to be grounded.
Under the coil is a rubber washer / insulator. Under that is a spring type bushing. That bushing must protrude through the dizzy cap and make contact with the rotor.
With the coil dust cover off, you can verify all color-coded wires are in the correct spot in the cap.
Always the "slim" possibility that a wire is not on the starter solenoid that supplies juice.
I believe all the safety (start) switches such as neutral, clutch depressed, etc would not allow a crank mode. You have crank / no start mode.
You changed the coil. Did you find and connect a black small gauge wire to one corner of the coil frame?
(Some years did not have a wire but a GRD bracket instead) Regardless, the coil has to be grounded.
Under the coil is a rubber washer / insulator. Under that is a spring type bushing. That bushing must protrude through the dizzy cap and make contact with the rotor.
With the coil dust cover off, you can verify all color-coded wires are in the correct spot in the cap.
Always the "slim" possibility that a wire is not on the starter solenoid that supplies juice.
Thanks for bringing the ground wire up i was wondering about that i attached a pic of what i did is that ok or should i change it. Ground wire correct?
Also i looked at the starter wiring and its definitely a rats nest, surprised it cranks so hard. I will start there tomorrow.
If you have 12 volts at the batt terminal on the cap when the ignition is in run position you need to check the pickup coil. Other items in the distributor usually fail slowly while the pickup coil will be a hard fail. You can ohm it out as the leads plug into the module. You have to pull the distributor to replace as it's around the distributor shaft under the advance weights. You will see the 8 points on the reluctor.
Is it just me or just the photo, but the yellow and the red wires almost look melted coming out of the coil.
H-m-m-m-m-m-. ?????
Strange place for the number one plug-wire, but it works for you and that works too.
Just a note here.
Those coil frames are coated with a paint / sealant that keeps them from rusting. Does the paint hinder a excellent contact for the GRD wire? IDK
But I do advise to remove the GRD wires and wire brush to bare metal on that one corner.
Thanks for everyone's help, I greatly appreciate you guys babying me through this. As of now I got No power to the battery terminal on the cap. So now i enter the rats nest of wiring at the starter. @HeadsU.P. yes those wires fo look kinda melted in the pic but they are not, they are just junk Chinese **** parts what can you expect i guess. Also obviously the #1 plug in that position isn't working for me is it not supposed to be there? i was thinking of brushing the finishing off the coil for the very reason you stated. It has been done now. @DaveL82 I got the resistance from the pickup coil ,just to check it I know I have to get power to that terminal first, the pickup coil it was roughly 2.7. Can you tell if this is good or bad or am I just wasting your time.
I don't have my gm books here but I found a link saying between the pickup coil leads should be 550 to 800 ohms. Not sure if this is correct as I can't reference my books. They also mention measuring when the vacuum advance is operated to check for a broken wire.
If you don't have power at the batt terminal then that's the place to start.
The neutral safety switch was mentioned by someone. Try to start or get power to wire that connects to the batt terminal on coil with shifter in park and neutral. Sometimes this works if switch has a bad contact.
I would break this into two parts - Testing the wiring to the distributor and testing the distributor.
Testing wiring - continue with your investigation checking for 12 volts at the wire that connects to the distributor with the ignition in run and shifter in park and or neutral (doubting neutral safety switch as the starter works) I don't have a wiring diagram for your car but one should be available online. Do all the other car electrics seem to have power?
Testing the distributor - build up a test wire with a female crimp type connector on some 10 gauge wire (12 gauge should be ok for a test). The female crimp connector would connect to the batt terminal on the HEI coil. make the test wire long enough to get to battery or jumper cables that can connect to battery. This test wire will bypass the ignition switch. You can put a switch in the wire. With ignition in the run position replace the wire that connects to the coil with your test wire and turn car over looking for a a spark. If spark then check car wiring further. If no spark check distributor further.
@DaveL82 First off thanks for all the help. That's exactly the info i am looking for. I find it funny you mention neutral safety switch because:
This is the **** I get to work with. All the wiring in the whole thing is like this. Honesty not the worst but it's still like an adult mind ******* puzzle. I crank it with a pick or screwdriver. Oddly enough I got the headlights(of course they dont flip by themselves) and interior lights working. I was able to clear out what ever nested (literally) in the starter wiring. Maybe those ******* chewed something and it will be an easy fix. Yes I am aware I just screwed myself by saying that. In any case I am going to tackle that tomorrow, I am a single father and it's amazing to get any time to work on it. Thanks for all your help.
Allright, first of all as always thanks to all the people that are trying to help me. @Peterbuilt that was a great picture those help me more that the regular wiring diagrams. So I got power to the battery terminal and no spark. First i am going to put the old coil back on and see if it sparks. If not I am guessing the pickup coil or both coils are bad. Plus I also gotta find the break in continuity going to the battery terminal on the cap. One odd thing I noticed was that as soon as I jumped the battery terminals (cap bat terminal and regular battery terminals) the door ajar light started work when I opened the door. Had never seen that light on before.
It's kinda funny once you see it, forgot to plug that one back in. Sparks now just gotta find the break in continuity to the battery terminal on the cap.
75 with no spark!!!!!!
