6V tractor with 12V coil

[MIKE R]

oh, ok. nice photo then. paint looks great.

as much as I love ford red and grey and blue.. I also love the IH reds, case orange ( flambeau ), and the persion orange allis's

looking at a wd on the side of the road longingly right now.. it's calling to me...

The WD would go good with your G.

Now lets get back on the main topic of this thread it is getting off topic pretty quickly. 6V tractor with 12V coil

 

[DanB53]

Thanks for the input guys. I think I'll just leave it for now and see how it runs.

 

[Jerry/MT]

If you have a 6V system, you need a coil with 1.6 ohms reistance in the coil primary. This is usually called a 6V coil. A true 12 V coil will have a reisitance of 3.2 ohms in the primary part of the coil. This is to limit the primary current to a maximum of ~4 amps with 12v applied to the circuit.The are some so called "12V coils" that have a note printed on them "Use with a resistor". This is also a 1.6 ohm primary resistance coil.

Since you say you have a 6v electrical system, you'll need a coil with a 1.6 ohm primary resistance which will limit the primary current to ~4amps max.. A real 12 V coil on a 6v system will halve the primary current and make a weak spark.

 

[pat32rf]

The prior owner might have fried the 6 v coil, stuck in a 12v and found that it would start and run so left it with no ballast resistor. If he puts a 6v coil back in, then it will probably fry with no resistor.

 

[Soundguy]

why would a 6v coil fry on 6v? ford's about the only one innovative enough to do that trick. ie.. put a 4v coil in a 6v machine.. and a resistor that heats up when running.. thus giving you a cold start bump...