No spark!

[TNS_Datsun]

Ok,
Im about to pull my hair out! haha

I was driving my 620 a few days ago, I had just recently bought it and had drivien well over 60 miles or more. I left work one afternoon after putting new plugs and wires on. I was driving and all of the sudden I loose power and hear a sizzle noise. I pull over and and pop the hood, I see instantly my coil wire fell off. It was pluged into the distributor but not to the coil. I figure "easy, plug it in and ill be on my way. NOPE! it wont start, it turns but nothing.

I was getting a semi weak spark from the coil, I replaced the coil, cap and rotor. I test all connections and getting 12 volts. I am getting 10 volts on crank at the coil + wire. I was getting no spark past the distributor, I replaced the ICM and now I get no spark what so ever.

I wired the coil and distributor with wire to bypass the harness, nothing.

Im so confused, I have power everywhere I need power but no spark! Does anyone have any good ideas for me to check? I am new to datsuns but I am a tech, Im still fairly green tho.

Thanks!

[datzenmike]

I hope you kept the old module, they rarely go bad and a new one is an unknown.

 

Check that the distributor is well grounded. Most matchbox style had a separate ground wire on a lug. The coil grounds through the distributor, so if poor or none it won't work well if at all.

 

Test the resistance of the coil primary with the wires off. It should be about 0.75 to 1 ohm. As you haven't driven it much possibly the PO replaced it with a points coil. They will burn up if used on an EI distributor system. The coil may say "Use With Ballast" on it?

[Nuclear Water Boy]

Good point!! Those modules last forever. If your running a ballet resistor ck the resistance across it chances are you fried it when the coil wire was tapping off the coil creating resistance/heat. As KingRat said ck and make sure. Also make sure the dizzy has a good ground. Don't depend on the pedestal as a ground Because there is an O-Ring in there that could create bad grounding issues. Attach a wire to the dizzy and then ground it.

[datzenmike]

I see that you replaced the coil so unlikely that's the problem. (hint: never throw stuff away)

 

If wiring the coil directly to the battery it must only be on the + side . Connecting to the neg. side will likely fry the module.

 

On the distributor the module must be wired this way with the battery positive to the B terminal

 

 

 

Connecting battery to the C terminal could burn the module out.

 

 

 

If it's wired properly the negative side of the coil should show an on and off pulsing battery reading while cranking. If not check the C terminal on the module. If still nothing take the cap off and crank. Does the rotor turn?

 

Are the Red and Green wires connected to the module properly. If backwards it may not get the signal from the reluctor.