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Discussion Starter · #1 ·
Purchased a Pertronix electronic igniton unit and installed in my 70 chevelle last week. Could only get it to pop and sputter but would not start. Got frustrated because I wanted to drive the car this past weekend so I RE-Converted back to Points. Now I can't even get a spit or a pop! Could someone walk me through the process of checking for spark?
I got TDC and my rotor was aligned with #1 spark plug wire. I've connected the 1 wire from the distributor to the - side of coil and connected 2 terminals (one with 2 cloth covered wires) and the other (canister at base of coil; condenser?) to the + side of coil. Is there a way to check the coil without a tester? Ex. Touch the coil wire to metal, turn key and look for spark or is that not the preferred method?


thanks,

Scott
 

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Sounds like the condenser is connected to the (+) coil. Wrong side. Actually you don't need it just to try and make a spark.
1, The points need to be set and open and close mechanically.
2, Points connected to (-) coil.
3, Voltage applied to (+) coil.
4, Rotate engine (distributor) and hold (safely) the large coil wire very near (small gap) its mounting bracket (metal).
Coil should put out a spark as the points open and close.
 

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Discussion Starter · #3 ·
John,
Let me make sure I've got this straight before I try this on my way home from work tonight:
The 2 cloth wires that come together under one terminal end get connected to the + side of the coil.
The wire from the distributor, the wire from the firewall(tach?) and the wire from this little canister(condenser?) that is mounted at the base of the coil all go to the - side of the coil.
If I get no spark when I carefully hold the coil wire near the bracket, what would be my next test? I don't understand what I screwed up because it worked fine when I took it out.
 

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"The 2 cloth wires that come together under one terminal end get connected to the + side of the coil."

Only one is cloth covered but this is the correct side. This is the 12 volt input. Should see 12 volts to ground, coming from the solenoid, while you are cranking the car.

"The wire from the distributor, the wire from the firewall(tach?) and the wire from this little canister(condenser?) that is mounted at the base of the coil all go to the - side of the coil.

Yes, but you don't need all of this to "get spark". All you need is the "wire from the distributor". This is the wire from one side of the points. The other side, of the points, are screwed down. This grounds the other side of the points. You also don't need the rotor or the distributor cap either to "get spark" out of the coil.

"If I get no spark when I carefully hold the coil wire near the bracket, what would be my next test? I don't understand what I screwed up because it worked fine when I took it out."

Points not set, no voltage into the (+) coil, bad coil. Coil is really a step-up transformer. Voltage in produces voltage out. Must spin the distributor (engine) to get a steady pulse out.
 

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Discussion Starter · #5 ·
I've got no spark coming out of the coil wire. Tried a different coil wire and still no spark. With the key turned on I have low voltage coming to the coil from the ignition wire and also have low voltage over at the points. Turn the key to start and no spark anywhere from the coil wire. Anyway to test the coil without buying a new one and trying it?
 

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You should see around 2 ohms across the coil primary (+) to (-) with no wires attached to the coil. Not a great test and doesn't fully check out the coil. Replacing it is usually what's done if it is suspected to be a problem.

You should have a full 12 volts, on (+) coil while cranking the car. This comes from the starter. Otherwise with just the key on you will see 7-12 volts on (+) coil depending if the points are open or closed.
 

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Discussion Starter · #7 ·
Thanks John. I'll test it tonight.
May have found another problem last night and wanted your opinion;
While checking the resistor wire(yellow cloth covered) for any problems, I found it sort of melted fast to a black wire with a pink stripe in the harness after I peeled some of the tape off. Didn't seem to damage the resistor wire but the black one melted right down to the copper strands for about 2 inches of the length of wire. Any idea what this wire is and what damage it may have caused?
 

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Can't answer the wire location off the top of my head. Sort of an odd color. Might try looking around the horn relay, idle stop solenoid, or the TCS relay for the other end.
 
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