When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Hey guys im on the home stretch of my rebuild, im new to this all and have learnt mostly everything along the way from your guys help.
Im using my wiring harness from my (79 f250 that had a 400)
The truck now has a 390fe and the harness was in rough shape)
Everything so far has been going great, theres a few little things here and there that i will ask as i go.
My main question is the troubles im going to have hooking into the actual engine.
as it looks so far the ignition coil has a different setup.
any advice much appreciated?
Does the 390 have a points distributor or a duraspark dizzy? If you aren't sure what year is the 390? I believe 1975 and down is point and 1976 and up is duraspark but I might be off a year or two.
To my knowledge that would be the only difference between the wire harnesses.
i plan to buy a new distributor and ignition coil.
if buy them for the 390, what will the connections look like? just wires that i have to splice into my harness? because the 400 harness has a plug that plus into the distributor and hard wired into the ignition coil.
i plan to buy a new distributor and ignition coil.
if buy them for the 390, what will the connections look like? just wires that i have to splice into my harness? because the 400 harness has a plug that plus into the distributor and hard wired into the ignition coil.
All you should need to do is get a distributor for a '76 390. This will use the same plugs as the '79 400.
Don't use a '74 or '75 DS distributor. Each one of those is different and won't plug into your harness, the '76 will.
Does the 390 have a points distributor or a duraspark dizzy? If you aren't sure what year is the 390? I believe 1975 and down is point and 1976 and up is duraspark but I might be off a year or two.
To my knowledge that would be the only difference between the wire harnesses.
Krazy, just for future reference, the DuraSpark was first offered as an option in '74 and continued as optional in '75. In 1976 Ford made the DS ignition standard and released the Dura-Spark II with the blue grommet module, this one continued into the '90s.
The '74 and '75 modules are each unique to the year and don't interchange with either themselves or any other year. The '74 and '75 plugs on the harness are also unique to each year.
Was that under the dash?
It looks like the "emissions throttle kicker solenoid actuator"
Pull the tag off and see if the number on it is D7HF-9F441-AA.
question #3
the harness from my 79 plugged into my transmission (400m/c6)
But the (390/c6) that i have in it now from my 74 didnt have a plug to mate.
Is this something i can just leave unplugged on the harness?
That's the NSS, neutral start switch. It controls both the neutral start and the back-up lights.
73-77 the NSS was mounted on the steering column. In '78 it was moved to the side of the transmission.
I would recommend installing it just for the neutral start if nothing else.
To use the 73-77 style switch, you'll need to swap to the earlier steering column.
To use the later switch on the earlier trans, two things, first, you'll need to be able to mount the switch on the side of the transmission. There are two bosses that are cast into the transmission case. The earlier case may or may not have them. If it does have them, they may need to be drilled and tapped to mount the switch.
If you can mount the switch, you'll need to swap the manual gearshift selector lever. These will interchange between the two transmissions without problem. You need to pull the pan and remove the 7/8" nut that holds the arm in.
If push comes to shove, you can bypass the neutral start function so you can start it by jumping the two wires in the plug.
Long female plug that i have labeled gas tank, i have both tanks wired to the sending units off the main harness. but i can not remember where this guy goes. i was thinking to the tank selector, but it doesn't match in.
any idea?
