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underdogkev · 03-04-2011, 02:40 PM

So, I have a simmilar problem with my 72 GMC 350. No spark from coil. Problem seems to be a power issue. I only have 5 volts at the positive post on the coil. Have tried many solutions. None working. I have twelve until the final conection is made. That being the red wire from the neg post on coil to the points. with that wire off I have 12 volts and I now thats too much but when I make that connection it drops to 5 volts. I have changed wire. Same thing. I have done a complete tune on truck. Re timed complete. All new parts except distributor. New rotor, cap, plugs, wires, coil, resistor, points and condenser. Truck ran poorly before tune at higher speeds, so thus the tune up but like I said now I dont have any spark from coil and some strange power loss issue. Kicing myself now but wish I would have gone HEI. Wife wouldnt let me, its "her" truck and wants to keep original.
Any help would be greatly appriceated. Thanks guys!

03-04-2011, 02:40 PM	#23
underdogkev Registered User Join Date: Feb 2011 Location: boise idaho Posts: 1	Re: no spark So, I have a simmilar problem with my 72 GMC 350. No spark from coil. Problem seems to be a power issue. I only have 5 volts at the positive post on the coil. Have tried many solutions. None working. I have twelve until the final conection is made. That being the red wire from the neg post on coil to the points. with that wire off I have 12 volts and I now thats too much but when I make that connection it drops to 5 volts. I have changed wire. Same thing. I have done a complete tune on truck. Re timed complete. All new parts except distributor. New rotor, cap, plugs, wires, coil, resistor, points and condenser. Truck ran poorly before tune at higher speeds, so thus the tune up but like I said now I dont have any spark from coil and some strange power loss issue. Kicing myself now but wish I would have gone HEI. Wife wouldnt let me, its "her" truck and wants to keep original. Any help would be greatly appriceated. Thanks guys!