Ford ballast resistor

[butch27]

On my engine in my rod ('68 Ford 302) does the wire from the starter solenoid go to the ballast first or straight to the POS side of the coil THEN to the resistor? Thanks Butch

[enjenjo]

It can connect to either place, as long as it's on the same wire. the end of the ballast that goes to the coil, or at the coil itself.

[The Paisano]

I figure you have a ballast resister installed into the 68.that's not a factory part.I recall that the 68 and up to the point where they changed over to solid state circuits in later part of 72 the the resister for the ignition was a pink rubberized wire with a solid stainless core.this was the ignition side of the run system.I used to have to repair these all the time

[butch27]

Correct: It's really wired as about a '66 Ford or so. Nostalgia style.

[wayne petty]

on ford starter solenoids... the I terminal..  connects that circuit to full battery power during cranking...

how it does it???  it has a spring loaded contact that the solenoid disc comes up and contacts when the solenoid is engaged.

when the key is on..  there is a resistor or resistance wire between the ign switch and the coil + terminal.. and another normal piece of wire that runs over to the starter solenoid I terminal...   when the solenoid is off.. the coil gets reduced voltage ... 9.6 to 10 volts usually,,,  when the engine is being cranked... the I terminal bypasses the whole ignition switch and sends battery cranking voltage to the coil.... usually about 12.3 volts...

on ford duraspark 2 electronic ignitions..(with the blue grommet) . the white wire to the module is hooked to the I terminal...   when this white wire gets power.. it retards the timing in the module 10 degrees to make it easier to start...

on most ignition switches with points as a factory install.. when you turn the key to the crank position ,  the power to the coil is cut at the ignition switch... it depends on the solenoid bypass circuit to power the coil..  cutting the power during cranking makes for hard to start cars when the bypass wire gets disconnected ... as the car loses power during cranking.. and when you release the key.. the engine catches...

later model cars with electronic ignition keep the power to the coil on during cranking..     so it might pay to test the ignition switch...


on gm starter solenoids... the R terminal powers the bypass circuit... just like the ford units... hei ignitions like full battery voltage all the time.. so putting HEI in a car that came with points.. one might really think about installing a 30 amp relay where the coil + wire was... so the coil+ wire only powers the relay winding... the power for the hei comes though the pin 30 wire and that is hooked to battery voltage closer than the ignition switch...

some gm cars with points have later models that use similar ignition switches. they can sometimes be retrofit from later years without the break the power to the ign 1 circuit power during cranking..

a digital volt meter set at continuity beep will tell the easiest.

again.. hope this helps someone...