F100 with 3.8L SC transplant - no pulse

jclars

Registered User
I moved the entire wiring harness from the 89 SC to the 56 F100 pick-up over Christmas break, hooked up the vital harness connections, but nothing getting past the starter relay. Of course, I didnt record the connections there with a sketch or picture, thinking it would surely be obvious.

I have searched this site for a specific wiring description that shows which wire goes to which post. Nothing in Haynes either. I have one wire that has a curious Y on it that is bonded together with plastic, but appears like it was intended to land on different posts.

Can anyone show a schematic or picture or describe the 89 relay connections.

Thanks,
John L.
 

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89 Will be fun as it will require an actual book and I'd only trust a Ford EVTM and not Hayes.

Got Fuel and Spark?

Hope the pic is just reference and not how the start was attempted.
 
Haha, I figured that pic would get a reaction. Yes, the front and cab are in place. I situated the electrical close to where the T-bird had them, so orientation is roughly the same.

Hoping someone can just get me started at the front. I am almost positive there will be more problems as I try to get this thing going.

John L.
 

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What are you saying, the engine won't crank? Is the neutral safety switch hooked up? Or clutch switch? Can't remember if its manual or auto? I would guess auto.
 
nice

the way the picture is of the enginebay looks like it was made for that shape especially at the oil dipstick & tubing ....

hope you get it running soon .... and yes will be really fun to drive..;)
 
No power going beyond the starter solenoid. I am assuming I may have the posts reversed. Or some of the wiring not bridging across the posts if necessary. It is an aftermarket relay.

Looking at the Haynes manual, it shows that the EEC should always have power. Also the fuse block. I dont seem to be getting past go and just don't want to fry anything.

It is an automatic. The original controls and tranny wiring are connected.

Thanks,
John L.
 
Make sure the ground straps are connected that go to the motor mounts there should be one on both sides. Also I would advise you not to attempt to start that motor dry they heat up very quick without coolant and you can warp the heads very easily. It not starting for you yet may have been a blessing in disguise. The posts on the sulenoid cant be reversed i dont think you can make it fit the black plastic connector woth the two posts on it will have the fuse box and all the other loop connectors on the post thats closest to the fire wall the one toward the core support only has the one connector i believe
 
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Thanks Dave,

I dont plan on starting it just yet, although it is ready to receive fluids. This is a shake down of the electrical, but obviously a little shakey for sure.

Is the single wire on the one post by itself the + battery cable? Or the thick starter wire?

I will probably keep this thread active as the shakedown proceeds. The good news is that I am getting more familiar with electrical functions.

John L.
 
Ford used the solenoid as a terminal block too so if you don't have the Alternator wire and like on the same post as the battery cable wont get fire.

The solenoid can not be wired backward. The ignition switch goes to the #10 post and 3/8" posts are the switched so as long as the Alternator wires are on the same side as the constant hot it should work.
 
Thanks Bowez, last night I googled Ford starter relay and found lots of examples. It confirms what you say. All leads on one side with the battery, the other post is starter wire only. I did not go check yet, but I am guessing the Y has the alternator wire which can go on either post.

For future reference, here are some Ford picture examples. After not finding my answer on a search of this post, I can see I should have titled the post more appropriately.
 

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The SC engine does indeed fit like it was meant to be. It continually gets comments that way. It seems like such a perfect match, it makes me wonder why it is not more popular with hot rodders. Oh, yeah, the carbeurated V8 thing.

But the interior is benefitting from the SC too.

Thanks for all the help.

John L.
 

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good job

I like this swap I think it will make a great driving truck. Would be cool to you the rear suspension and rear end in it. Cool project.

Dave377
 
Attached is how I ended up attaching the stock SC wiring to the aftermarket starter relay. The small wire is attached to the S post rather than the I post that you see on top.

The first sign of life was that one of the front amber lights started blinking. The second sound of life was a buzzing from behind the instrument cluster. This makes me ask the question, is there an alarm that needs to be disabled? Or a stuck blinker relay? Or a crossed wire at the relay? (blinker switch is off).

I will know better when I can have another person touching the battery post while I can determine the exact source of the buzz.

I am only touching the battery post with the connector at this time. No solid connection has been made yet.

Please let me know if the pictured arrangement looks wrong. The wires seemed to fall into place with this layout.

Thanks,
John L.
 

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Yes it is wrong but not by much

It is close, what you want to do is move the greyish alternator wire to the other post on the solenoid and you'll be good to go least at that point :)

Now the buzzing/turn signal thing may have a thing with something not hooked up right down the line?
 
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brake pedal

i am not sure if the 89 had this but you automatic you'll need to press the brake pedal in order to start also check the the shifter that is in park position or neutral i don't know if this could be miss alined or not hook up.... this just came up to my mind also for future did you put the inertia switch too? i know this is for the fuel but thinking ahead this switches just by dropping they get activated really easy...
 
So the top wire on the rearward post should be on the hot terminal?

Thanks,
John L.

Correct, just leave the one wire with the "aftermarket" terminal on it.

Else if you were to start the car, and the alternator started to charge, you'll end up engaging the starter :eek:
 
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