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Basic Wiring to Start Engine

AZreGuy

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Oct 2, 2017
Messages
17
What are the basic wires needed to start a 68 EB with a 1971 302 in it? Rats ate a bunch of wires and I just need to get it started to see what I am dealing with. I will get a full wire harness but want to know how engine is as I may have to change it and possibly be adding EFI and electric wipers etc. to start there is a 3 wire harness on top of engine and I think 1 of them goes to the distributor or coil but not sure which one and the other 2 I do not think are needed to start it. There is only a broken wire coming off the coil and 1 hanging off the dizzy. There are a bunch of wires on the starter relay but not sure where they go either.
 

73azbronco

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Nov 11, 2007
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7,796
googling:

There are two areas you need to hook up to get the engine to start and run: Ignition, and Start. You really don't need the Generator/Alternator, but you will have to charge your Battery somehow later.

Parts you will need to get: 12 volt (four post) Starter Solenoid; two post non grounding Starter Button (unless your ignition switch has a "start" position);
12 volt Coil ( I strongly recommend the Petronix "Flame Thrower"); Ballast Resistor; 12 volt Points, and Condenser.

OK Ignition:

All you need to have is power coming from your Starter Solenoid - the one with the POSITIVE Battery Cable hooked to it- hooked up to the "B" or "BATT" post on your Ignition Switch.

Then run a wire off the "I" or "IGN" post of the Ignition Switch to one tab of a Ballast Resistor out the other end of the Ballast Resistor to the POSITIVE post of a 12 volt Coil.

Hook your Distributor wire (from the Points - I think it's white) to the NEGATIVE post on the Coil!

Run one more wire from the POSITIVE post of the Coil to the small "I" post on the Starter Solenoid.

Ignition is done.

Now, run a Battery Cable off the POSITIVE post of the Battery to the large "B" lug (or the one with the wire going to the Ignition Switch), of the new 12 volt (four post) Starter Solenoid.

Run a battery type cable with two eye ring terminals from the other large lug of the Starter Solenoid down to the Starter.

Connect the end of you other Battery Cable to one of the Starter mounting bolts. But don't hook it to the Battery until you are ready to start up the Engine.

Run a 14 AWG wire from the "A" or "ACC" post of the Ignition Switch to a TWO POST Starter Sutton then out the other post of the Starter Button to the "S" small post of the Starter Solenoid.

Start circuit is now complete and the truck will start and run (provided the battery is charged).

If you want to hook up the Generator or Alternator to work, hook up the Regulator to it as you normally would, then run out the "power out" wire ( the same with a one wire just no regulator) to the same post on the Starter Solenoid as the POSITIVE Battery Cable.
 

B RON CO

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Jun 29, 2016
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Statesville, NC
Hi. First make sure the ground from the negative post on the battery to the engine block is still in one piece.
If the engine cranks when you turn the key you need to repair or replace the wire from the - (distributor) side of the coil to the points. Them you can run a jumper from the battery to the + (battery) side of the coil. When you connect the battery to the coil the primary ignition is "hot", and when you crank the motor is should have spark, and run. To shut it off, remove the jumper wire from the coil or battery.
If the engine does not spin with the key you can test and jump the solenoid. Check the heavy wire from the battery to the solenoid, and the solenoid to the starter for damage.If they look good, remove the small wire from under the big wire that comes from the battery. You can test the little wire by using a test light and seeing if it is hot when a helper turns the key to "start" The little wire is from the ignition switch, and is only hot when the key is turned to start, to activated the solenoid, and spin the starter. If the little wire is not working, you can use a remote starter switch or just jump the big wire post from the battery to the little post (with the little wire disconnected) with a big screwdriver to activate the solenoid and the starter should spin.
That is the easiest way to hot wire the ignition and jump the starter.
Note that you will get a nice spark at the solenoid, only temporary, and you will not get a shock, and also don't leave the coil hooked up when the engine is not running. Good luck
 

DirtDonk

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Nov 3, 2003
Messages
47,355
Verify which distributor you have too of course. If it's a stock '71 then it's just points with one Black wire that goes to the negative side of the coil like 73az said.
If it has been converted using one of the aftermarket electronic trigger units it will have at least two wires. If it's a Duraspark it will have three wires.

Did the rats get just under the hood, or inside under the dash too?

Paul
 
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AZreGuy

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Oct 2, 2017
Messages
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Been pretty busy so have not tried to start yet. A load came in from LMC so I can put gas tanks back in.
1 black wire is on dizzy. Have not checked out under dash yet for wire issues.
 
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AZreGuy

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Oct 2, 2017
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Well the bronco started today but fuel is gushing out of the 2 post holes in front of the carb!
I did rebuild the carb to what I could do. The choke linkage on the right looks like what I see in net pics and how it looked when I took pics before taking apart. However the screw to adjust something touches nothing and the linkage on the left side just swings away so I put the spring in it to pull it forward to make some sense but not sure if it is right either. It has a 2bbl carb on it.
 

B RON CO

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Statesville, NC
Hi, if fuel is coming up out of the vents there is something wrong with the float, or needle and seat. Time to remove the top of the carb. Good luck
 

Pa PITT

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Jul 15, 2005
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Loc.
Stephenville TEXAS
I'M going to subscribe ...AS I've got a 68 Bronco setting in my shop that hasn't ran in 15 years but it'll turn over with a torque bar. I've started to work on it several times .. But I get side tracked. & Never go back. It'd like to hear it run.
 

lonesouth

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Dec 18, 2003
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Here you go

http://classicbroncos.com/forums/showthread.php?t=102944

attachment.php
 

DirtDonk

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Nov 3, 2003
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47,355
Well the bronco started today but fuel is gushing out of the 2 post holes in front of the carb!

As said, those are float-bowl vents, so your float bowl is overflowing.
The possible causes are incorrect float level set when you were rebuilding, fuel pressure too high (not likely if it's just a standard pump), or the needle-n-seat not sealing properly and allowing fuel to flow in uncontrollably.
As said too, time to pop the top to check it.

The choke linkage on the right looks like what I see in net pics and how it looked when I took pics before taking apart. However the screw to adjust something touches nothing and the linkage on the left side just swings away so I put the spring in it to pull it forward to make some sense but not sure if it is right either.

The high-idle screw needs to touch on the steps (there should be one with a "V" next to it) on the idle cam. This is ONLY touching when the choke plate is closed however. When the plate opens and the choke is "off" the curb idle/main idle screw is the only thing touching.
But if you say it's not touching when cold and the plate is closed, then your linkage is either bound up, the cam plate is sticking and not sliding into place, or the screw is not adjusted.

Did you have the butterfly plates out from the base of the carb? If so they may not be in properly and keeping the mainshaft from closing all the way down. This would give you a high and rough idle even without any of the screws touching.

Can you post a detailed close up shot of the carburetor on both sides? Not sure if that's possible, but if you can that might help one of the carb gurus see what's up.

Good luck.

Paul
 
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AZreGuy

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Oct 2, 2017
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I took the carb apart and what I did was not replace the seat as the original one had a screen on it and I thought that was extra filtering. I replaced the seat that came with the kit and no more problems
 
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AZreGuy

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Oct 2, 2017
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Now the issue is in next step of brakes. I do not want to replace system yet as I may go power disc on all corners but still just wanting the rig to move.
Issue is I cannot get any lines to bleed at wheel cylinders.
Time to search on that now. I did search carb issue yesterday and found where I will be there in start on that.
 

B RON CO

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Jun 29, 2016
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Loc.
Statesville, NC
Hi, I would fill the master cylinder and slowly and gently pump the pedal a few times. Next open the rear wheel cylinder bleeders and let it gravity bleed (no pumping). Next, do the fronts. You should get fluid out of the wheel cylinders that way. You may need new wheel cylinders. One or both pistons in each wheel cylinder may be frozen. Why don't you start a brake thread after you get the Bronco to run.
 
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