ohms in a coil

[abe]

Can anyone tell me something about ohms in a coil? I bought a new coil at a parts store 2 weeks ago. Then I decided to buy an electronic ignition. That company says your coil must have 1.5 ohms of primary resistance. Obviously I don't want to buy another coil. Of course the electronic ignition company wants to sell their coils. I called the parts store to ask them what the ohms was on the coil. They looked in their books but could not find it.

This coil is for a 1970 F350 with a 360. On the coil are printed these words: "12V use with primary resistance wire or external resistor 067." I called the local auto electric shop that rebuilt my starter and told me my old coil was bad. They can not tell what the primary resistance is on a coil, only if it is good or bad. He recommended looking in a 1970 truck shop manual.

Can anyone help me? A Pertronix Flame Thrower coil costs $31.95. I don't know if I can take my other coil back to the parts store. It has been on the truck but driven only 4 miles......

Happy New Year!
Thanks, Abe

[kf7mjf]

Do you have access to an ohmmeter?

If so, the instructions on this page will work for you http://www.ehow.com/how_6747725_trouble ... -coil.html

Or just buy a new hot coil.

[jefeys]

take ohm meter to auto parts store
see what the new reads..

[Nitekruizer]

So far, every one of the "yellow top" coils that I have ever tested has had a primary resistance of 3-4 ohms, even though the specs that I have say they should have a primary resistance of 1.4 - 1.6 ohms, and these coils are good working coils too.
The coils used with Ford breakerless systems, the Duraspark systems, according to the specs, should have a primary resistance between 0.7 - 1.25 ohms. IHTH

[abe]

The parts store had no idea how many ohms--- I bought a multimeter on sale at the local Sears store. The primary resistance measured at 1.5ohms.... just what I needed. The coil is in, the electronic ignition is in and the truck is running fine..... with thanks to the guys here for all their help...