The Stovebolt Site Forums The Shop Area The Electrical Bay Starting up a 250, spark!

After rebulilding the 250 in my 69 c10, I finally went to start it for the first time. When I turned the key the motor was turning and then it looked like a big spark came from the coil. Now the engine will turn, but will not fire.

1) Is it a bad coil?
2) Could I have installed the dizzy wrong, causing the coil to throw a spark!
3) Did I wire something incorrectly?

I was really excited to get the beast running after a year of sitting in the garage, but I am now in bummerland and the wife is not happy. (she wants her parking space back.)

It sounds like something is shorting out the secondary side of your coil. That big spark tells you that something is wrong. Make sure the coil tower (where the coil wire plugs in) is clean and dry. If you know the coil is clean and dry and if the coil wire is good, it is time to gt another coil.

Check the voltage to the coil , should be about 7 ~ 9 VDC & go to 12 VDC when you crank the engine .

Coil basic resistance test (wires off) is 1.5 ~ 1.9 OHMS between the two outer connectors .

Waxy stuff leaking out between the area where the plastic top meets the metal coil can is in fact wax (insulation) and means your coil is dead .

Lucky for you , Ontario Pick-A-Part is close by on Milliken Av. south of the I-10 freeway and you'll shortly find a nice brand new coil in there , if you need one , take along your Harbor Freight $2.99 multi-tester .

Please to note : if DPO has buggered upo the wiring in your truck and you find 12 VDC at the coil with the key on , you need an ignition coil that has 3.5 OHMS primary resisitance ! big differance here .

Never _ever_ leave the ignition key on whilst chasing electrical gremlins unless you put a scrap of plastic between the ignition points or you'll cook the coil .

If you're rich and decide to buy a new coil , get the better Epoxy filled one as it'll last longer .

I hope this helps...