I have a 1984 f250 extended cab long box 4wd manual transmission with a hipo built 460. Love the truck but when the wiring under the dash started smoking i decided it was time to fix it.

The problem with the wiring was easy. Multiple dead shorts related to the door buttons and the courtesy lights (its an xlt) Wired it all back up and it wouldnt start.

That was probably 4 months ago and unfortunatly i had to let it sit due to a lack of time.

Now i have time but can not for the life of me figure out what is wrong.

First i assumed the duraspark box went out. Its fine. Coils fine. Wiring is per fords wiring diagrams so i assume its fine. i have hot everywhere i need it. Ground everywhere i need it. But still can not get it to spark.

I have about six thousand dollars worth of parts sitting in my house waiting to get put in the truck but i dont want to start that until i can get it running.

Any ideas?

I looked and looked but could not find a wiring harness for the truck. (my money is still on bad wiring but it tests ok) at this point im thinking about finding a junk yard truck with a good body and good wiring to swap my motor and drivetrain into (DEFINANTLY dont want to loose either of those) its that frustrating.

Either that or buying some mallory or msd box that i can hook to the coil, positive, ground, and distirbutor and just bypass all the ford wiring and duraspark stuff ( i HATE wiring)

Any help would be greatly appriciated. just when i think i have this truck running something else completely irrational happens (had a rod chuck through the side of a ford factory motor with 75,000 miles!)

Thanks for any help or insights into the msd or mallory "fix"

 

Quote:

Originally Posted by skattnig

when the wiring under the dash started smoking i decided it was time to fix it.

The problem with the wiring was easy. Multiple dead shorts related to the door buttons and the courtesy lights (its an xlt) Wired it all back up and it wouldn't start.

My immediate suspicion is that the last change you made is the cause of it not
starting now. What door buttons are you referring to? Those that operate the
courtesy lamps when the doors are opened/closed? Or, for power windows &
locks? or, something else?

Most importantly, what were the colors of the wires you operated on when you
did this?

Can you easily UNdo what you did? That's prolly gonna be the best way of
determining if it's not starting because of something you just did to it.

 

I agree with Bra boy LOL. That avatar is crazy!!!

Maybe you burned some wires in the ignition switch. Popped a fuse or a link??

To bad you couldnt get a donor MSD box, just to see if it that circuit.

 

check to see if you have power at the duraspark module.if yes the problem is on the module side.if no the problem is between the plug and fuse block.if you have no power to the module i would lower the steering column and see if you have power at the ignition switch,if no power there there is a problem between there and the fuse block.good luck.

 

I have power at the ignition switch. Tried two different ones just to make sure.

I have power at the duraspark box. Just nothing past it. But the new box didnt fix it either.

When i redid the wiring it was the buttons that mount on the door frame down by the kick panels that operate the courtesy lamps and dome light when the doors were open, also the courtesy lamp wires themselves. I don't remember all the wire colors but i do remember one was bright green with a yellow strip. But it just ran from the fuse block to the courtesy lamps. Never to any other wires.

would a msd box fix this? I was planning on upgrading to msd eventually, this is a slow build show truck. Finally have most of the pieces i need to finish it. I was looking at the msd digital 6. I just dont know if it is a replacement or if it still uses the duraspark.

I like the duraspark, especially the low oil pressure cut off feature (saved my motor when it was blowing up rockers) but i just cant seem to get it fixed.

 

will it crank over when the key is turned?

 

Well, no. But it hasn't for a long long time. Im not exactly sure what the guy who owned it before me did but something he changed broke. And i could not even begin to figure out his little mechanism for starting the truck with the key, so it has a push button starter, which it will turn over with but its really nothing more than a jumper between the s terminal and the positive on the selonoid.

I can buy a 1986 f250 auto with a 360? doubtful on the motor but thats what the guy says, for 1360. Im considering going that route.

 

or get an E-Z wireing harnes for $130.00 at a local hotrod shop Painless are much more. Figure out how many circuits you need, buy the harness, and wire it up.

 

that thought crossed my mind as well. However when it comes to wiring,

A. i am somewhat good at it as long as i have a wiring diagram and the wires are all the right color

B. i hate wiring, cant stand it, but its looking like i'm going to have to do something like that...

a crazy thought, is it possible the magnetic pick up went out in my distributor? therefore not telling the box when to spark therefore not telling the coil to spark? is there anyway to test this?

 

Quote:

Originally Posted by skattnig

Well, no. But it hasn't for a long long time. Im not exactly sure what the guy who owned it before me did but something he changed broke. And i could not even begin to figure out his little mechanism for starting the truck with the key, so it has a push button starter, which it will turn over with but its really nothing more than a jumper between the s terminal and the positive on the selonoid.

IIRC even though you may be bypassing the key switch (by using that rigged-in
button) I think you still need to have that red/blue stripe wire hooked to the
solenoid in order for the ignition to get the right power at the right time. The coil
gets something like 6-8 (or so) volts in RUN but gets full battery voltage when the
key switch is in the START position.

 

Which it still is. I left all the wires stock i just added two. Well i guess we will see. I pulled the truck in the shop, pushed rather, last night and got the wiring back out of it, so now i'll go through that again

 

First thing I would do is check to see if you are getting fuel to the engine.

Then the second thing is...

Get a Multimeter.

Then I would remove the DSII harness from the truck, unwrap the black wrap around the wires, and use the multimeter set to OHMs and check the continuity of each wire in turn between the connectors. Check for cracks in the insulation, burn marks etc... repair as needed, then rewrap the harness like original, with black electrical tape. This will make sure the DSII harness is in good shape.

Then plug the harness back in, then with the ignition switch in the run position, check to see that you are getting power at the coil. Red/Lt Green Wire. With the ballast resistor in line voltage will drop to 6-8 volts in run, and you will get a full 12 volts in start.

If so then check the coils primary and secondary resistance using the multimeter.

Primary Coil Resistance
1. Unplug the coil.
2: Measure the primary resistance between the Batt and Tach test terminals. 0.8 to 1.6 ohms. If out of spec, replace coil.

Secondary Coil Resistance.
1: Unplug Coil.
2: Measure the secondary resistance between the Batt and center terminal of the coil. 7,700 to 10,500 ohms. If not in spec, replace the coil.

Stator check. (Magnetic pickup)

1: Unplug the distributor harness. Inspect for damage etc...
2: Check the Stator resistance between the Purple and Orange wires. 400, to 1,000 ohms.
3: Now check the Isolation resistance. Attach one lead to distributor base, and the other to the Purple wire, and orange wires in turn. one at a time.
4: If the stator resistance is less or more than the specified resistance, and/or the stator isolation resistance is less than 70,000 ohms, replace the stator.

Have your ignition module checked at a local auto supply store.

That should check everything except the cap and rotor, and plug wires.

One thing that bothers me is with your start bypass button, the coil, and ignition module will not be placed in the proper start mode for starting, because you are not turning the key to start. You need to fix this system as well.

EDIT: Perhaps you have a bad or misadjusted Clutch switch. The clutch switch keeps the truck from being started unless the clutch is fully depressed to the floor. 1984 and newer.

And as always, Good luck.

 

The engine is getting fuel.

And, Wow. That is amazingly great information. Thank you very much. I will definantly try all those tests when i get home.

As far as the button goes i know its a bad setup but i havent been able to find a decent steering column in any of the junkyards (truck needs one very badly) and i was planning on fixing it when i fixed the column.

Which leads me to another question. What exactly do these trucks use to crank the engine over? Is it in the ignition switch? the one bolted down on the column that the actuator rod from the key switch runs into, or is it a seperate switch?

 

Some guys here are pretty damn good and are experts in their fields; 81-F-150-Explorer is one of them.
[snip]Yes, that's the switch. You might get yourself a wiring diagram, they can be helpful....

 

I have a wiring diagram the full fold out ford mechanic set but even when i replaced the switch it still wouldnt start with the key. After removing the previous owners "aftermarket" ignition.
Looks like i have some research to do when i get home.