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coil resistance ?

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B

bluecoat

Freshman Member
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The readings on my 80 B coil (out of the car and in my warm kitchen) is 1.8 ohms between the side posts and 6,900 between either side post and the distributor plug port. According to Bentley the 1.8 is a little high but I can't find any info on the 6900 ohm reading, is it time for new coil?

Thanks
 
1.8 ohms sounds fine to me. Remember the MGBs from 75 on uses Ballast resistors along with the lower resistance coils. So if you sum the coil resistance and the ballast resistor (1.3 to 1.4ohms), you should get close to 3.0 ohms of resistance. That is the standard resistance for coils used in none-ballasted ignition systems.

FYI – I replaced my coil with a Pertronix performance coil a year or so back and it measured a little high as well at about 1.8 ohms. But should you decide to replace the coil make sure you order the “ballasted” Coil. Otherwise you will need to modify your system and remove the ballast resistor in order for your ignition to work properly.
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[ 02-12-2004: Message edited by: Bret ]</p>
 
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