Bad coil resister

Glenn D

Member
Hi folks

Have n front mount 12v converted 2n. Went and changed out a flakey ignition toggle switch and found an equally flakey resister it's the proper behind the dash one. What happens when these fail? I expected them to just be dead when they die. In this case when cold and just starting there's barely enough current through it to light a test light. So if I jumper it the engine will start but only run for a few minutes and it won't be passing any current when the engine stalls. While it's running the test light is bright on both sides. Once I start it (jumping the resister ) engine runs smooth and strong for a while.
 
They usually fail open, meaning no current flows at all.

Give it time.

Pretty soon it will do that.

But I think I'd just replace it now.

Any other resistors ion the circuit or do you have a 12v coil?
75 Tips
 

No other resister amd it's supposedly a 12v coil. This one has been really good all wintrr always started before cleaned all text onennections I've had apart just double checkng them now.

I'm working on first warm sunny day of spring time ... may take a while :)
 

Found on the amp Guage where I guess heat made the plastic recede and losened the connection there. I attached the leads the the same terminal until I get a new gauge. Won't start at all now. Good continuity to the coil. And the connection at the coil blinks when it's turning over might be flooded.
 
Glen..........did YOU do the 12-volt conversion? Heres the deal, whether the original 6-volt square can coil or the modern 12-volt square can coil, BOTH take the same "infamous" ballast resistor. From yer description, sounds like someone has also included a 12-to-6 volt converting resistor. Iff'n you use BOTH the modern 12-volt coil and a 12-to-6 volt converting resistor, you won't gittchur sparkies to sparkle. Ittza LAW, Kerchoffs Law. (resistors in series) Yeah, the original ignition switch is a weak sister switch. I replaced mine 3-times one summer fer just brush hoggin' and then I gott GRYPPED and went to a marine store and botta WATERPROOF toggle switch and have had NO MORE problems with my eazy starting 6-volt 8N.........HTH, the amazed Dell
 
(quoted from post at 17:56:03 04/15/16) Glen..........did YOU do the 12-volt conversion? Heres the deal, whether the original 6-volt square can coil or the modern 12-volt square can coil, BOTH take the same "infamous" ballast resistor. From yer description, sounds like someone has also included a 12-to-6 volt converting resistor. Iff'n you use BOTH the modern 12-volt coil and a 12-to-6 volt converting resistor, you won't gittchur sparkies to sparkle. Ittza LAW, Kerchoffs Law. (resistors in series) Yeah, the original ignition switch is a weak sister switch. I replaced mine 3-times one summer fer just brush hoggin' and then I gott GRYPPED and went to a marine store and botta WATERPROOF toggle switch and have had NO MORE problems with my eazy starting 6-volt 8N.........HTH, the amazed Dell
On this one I don't think 8 did the 12v I have 9n and 8n and did those. No oher resister. So kerchoff can relax. Put new plugs in and off it went but I still suspect the resister is bad the ammeter too. HaD a little trouble getting a waterproof toggle .. couldn't even get a boot for the cheapo one so I put a push pull in that I've had good luck with on the 9n
 
Glen.........both the infamous ballast resistor and the AMMETER are like light bulbs, they either work or they don't. .........the amazed Dell
 

Ammeter has a melted terminal from ai guess a loose connection. Have to see abut the resister. It always has voltage in some times no voltage out.... must be ghosts
 

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