hot coil

[Higgy62]

Hi one of my coils is getting a bit warm.. the bike isn't running ive got ignition on and rigged up to a battery while im messing with other stuff.. just noticed it very warm to touch while other coil is cold... is it just knackerd. its a 82 2a2 sohc.... and what ohms rating do I need for that model ... many thanks

 

[drewpy]

coils will burn ou if left with ignition on without running the engine. If the other is cold could be a feed or ground issue, you'll need to test it as per manual

 

[Higgy62]

coils will burn ou if left with ignition on without running the engine. If the other is cold could be a feed or ground issue, you'll need to test it as per manual

Thanks for the reply.il take a look.... cheers..ps when I spin it over on the starter ive got good spark to both plugs.. kill switch works and cuts power etc etc.. but the engine is not yet at the stage to fire it up.(carb issues)...have you ever tried after market coils.are they any good.i see there are a lot of second hand ones on ebay. .thanks Drewpy

 

[kshansen]

Which ever coil has the points closed on with engine not running but key is on will get hot. Had an old car once that was not starting and we gave up on it for the day then next morning went out to try an start battery was dead opened hood to put it on charger. That was when we found a large rats nest of fine wire. Seems the key had been left one and the coil got so hot it actually exploded!

Just remember if the coil has a primary resistance of say 4 ohms and the battery is putting out 12 volts it will be drawing 3 amps and those 3 amps will convert to 36 watts of power, in this case heat. So imagine wrapping a 36 watt light bulb in epoxy insulation and it will get hot!

 

[drewpy]

after market coils are fine, I got a pair on mine, but will need to change them due to me upgrading to a new system (when I get round to it)

 

[Higgy62]

Which ever coil has the points closed on with engine not running but key is on will get hot. Had an old car once that was not starting and we gave up on it for the day then next morning went out to try an start battery was dead opened hood to put it on charger. That was when we found a large rats nest of fine wire. Seems the key had been left one and the coil got so hot it actually exploded!

Just remember if the coil has a primary resistance of say 4 ohms and the battery is putting out 12 volts it will be drawing 3 amps and those 3 amps will convert to 36 watts of power, in this case heat. So imagine wrapping a 36 watt light bulb in epoxy insulation and it will get hot!

Cheers for that mate.. something to ponder