# Ford 8n running rough



## Vince8n (Sep 6, 2020)

Hello new to the forum! I have a Ford 8n that’s converted to 12v. With a front mount distributor. Recently replaced the distributor, coil and cap and it will run fine at idle but when reving it up it starts to miss and backfires. Unless! I put the battery charger on it with the tractor running and turn it on to 40amp and it will run like a top! Shut the charger off and it will suddenly go back to missing and back firing. I’m stumped!! Battery seems good I never have to boost it


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## Ultradog (Feb 27, 2005)

"Battery seems good..."
Seems good?
We dont recommend working off hunches.
Bring the battery in and have it load tested.


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## Bob 2 (Sep 6, 2020)

Capacitor in the distributor can cause rough running or engine shutting down. Even a new one can fail. If your tractor is still running rough, grab a few caps, install one, and see what happens.


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## Clifford B. (Nov 20, 2019)

Ya might check yer alternator output too, while running at working speed 
ya should git 13 1/2 to 14 1/2 volts but if the battery is bad it will eat up most all of yer available voltage to the ignition BTDT.........


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## Harold Piskura (Sep 25, 2020)

Is the new coil a 12 V coil? Is the resistor still wired inline? Ignition wire to + terminal?


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