The coyse of the curl

Dave H (MI)

Well-known Member
Well, not really a curse but I do need to replace the coil on my 1947 Farmall B. This was the first tractor I took from lawn art to running tractor back in 1997, with much help from the sage masters past and present on this forum I might add. I have checked my archives from back in the day and tested the coil as recommended then and I am pretty sure the coil has gone south on me. This tractor is a 12v conversion and I want to make sure I get the right coil. I crossed off 6v but I am seeing 12v with internal resistors (thinking this is wrong) and 12v with external resistor (which I am thinking is right just without the resistor). I have no resistor anywhere in the ignition circuit that I am aware of. The child behind the parts counter just gives me a blank stare when I ask questions so I am putting the question here. Just a straight 12v coil without any resistors?
 
(quoted from post at 11:20:46 11/27/12) Well, not really a curse but I do need to replace the coil on my 1947 Farmall B. This was the first tractor I took from lawn art to running tractor back in 1997, with much help from the sage masters past and present on this forum I might add. I have checked my archives from back in the day and tested the coil as recommended then and I am pretty sure the coil has gone south on me. This tractor is a 12v conversion and I want to make sure I get the right coil. I crossed off 6v but I am seeing 12v with internal resistors (thinking this is wrong) and 12v with external resistor (which I am thinking is right just without the resistor). I have no resistor anywhere in the ignition circuit that I am aware of. The child behind the parts counter just gives me a blank stare when I ask questions so I am putting the question here. Just a straight 12v coil without any resistors?

You need a 12 volt, no external resistor required, ignition coil.
 
There are no "internal" resistors in coils. The primary is just wound with appropriate turns of wire to run on 12v. Rusty is correct
Jim
 
I thank you guys! That is what I thought. By the by, both of you have posts in my archives on this tractor from back in 1997.
 
Go to NAPA and get you the IC14SB coil this will solve your problem should cost in the high teens. sold these for years for 12 volt conversions before I retired.
 
Might work OK there but is usually placed n before the coil. None needed if a 12v no external resistor coil is purchased. Jim
 
(quoted from post at 08:23:37 11/28/12) Sounds like a plan! Gonna run over there this morning. Thanks!

Maybe I shouldn't respond, because I don't really know what I'm talking about... but I remember a thread either on here, or one of those "other" tractor forums that talked about the coil being different on these old tractors because of the low rpms and the amount of time the coil was energized (had current flowing through it).

It sounded sensible to me; like the guy knew what he was talking about... I think the point being that you don't want a coil that is made for a high rpm automobile, and if you get the right one you shouldn't need the resistor.
 

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Back
Top