Big Blue's Transformation

[85lebaront2]

I forgot something in my last post - the original battery isolator relay. I need to figure out what to do.

 

The issue is that it is in the middle of the circuitry for the auxiliary battery volt meter. There's a key-on relay that connects that voltmeter to the aux battery post of the original isolator relay. Later, when the EFI goes in there will be a PDB on the driver's fender and that will house a key-on relay for the aux battery volt meter. But I need to decide what to do 'twixt now and then. As I see it there are two options:

 

1. Leave the lead from the aux battery to the original isolator relay in place but pull the trigger off the isolator relay. This would be easy. But if I find a junction block and replace the isolator relay with that then that might be the time to change?

 

Take the lead from the key-on relay off the isolator relay and extend it to the aux battery, but install an in-line fuse holder in the lead.

 

Just thinking...... Your thoughts welcome.

Gary, one of the items Ford changed in 1987 was the battery, it changed to a group 65 and the posts are reversed in location, basically the battery is rotated 180° so the posts are to the back and negative is nearest the fender. The other item, starting in 1992, the negative cable goes all the way to the lower starter bolt. Positive is a combined cable with the main cable going to the starter solenoid and a branch to the relay. The other side of the relay goes to the small terminal on the starter solenoid.The three wires (positive, negative and control) run together under the motor mount to the starter. The truck power is a double fusible link to the large yellow wire to the PDC on the left side behind the air filter and coolant/washer reservoir.

[ArdWrknTrk]

Gary, one of the items Ford changed in 1987 was the battery, it changed to a group 65 and the posts are reversed in location, basically the battery is rotated 180° so the posts are to the back and negative is nearest the fender. The other item, starting in 1992, the negative cable goes all the way to the lower starter bolt. Positive is a combined cable with the main cable going to the starter solenoid and a branch to the relay. The other side of the relay goes to the small terminal on the starter solenoid.

The three wires (positive, negative and control) run together under the motor mount to the starter. The truck power is a double fusible link to the large yellow wire to the PDC on the left side behind the air filter and coolant/washer reservoir.

And, again, Bill is entirely on top of things. 👑

[kramttocs]

I forgot something in my last post - the original battery isolator relay. I need to figure out what to do.

 

The issue is that it is in the middle of the circuitry for the auxiliary battery volt meter. There's a key-on relay that connects that voltmeter to the aux battery post of the original isolator relay. Later, when the EFI goes in there will be a PDB on the driver's fender and that will house a key-on relay for the aux battery volt meter. But I need to decide what to do 'twixt now and then. As I see it there are two options:

 

1. Leave the lead from the aux battery to the original isolator relay in place but pull the trigger off the isolator relay. This would be easy. But if I find a junction block and replace the isolator relay with that then that might be the time to change?

 

Take the lead from the key-on relay off the isolator relay and extend it to the aux battery, but install an in-line fuse holder in the lead.

 

Just thinking...... Your thoughts welcome.

I'd leave the solenoid there and disconnect the trigger. When you put the drivers side pdb in, extend the wire to a key on relay in there.No need for a fuse outside the pdb If you do want to keep a junction block there though, I can send you one. Have a couple on the shelf.

[Gary Lewis]

I'd leave the solenoid there and disconnect the trigger. When you put the drivers side pdb in, extend the wire to a key on relay in there.

No need for a fuse outside the pdb

If you do want to keep a junction block there though, I can send you one. Have a couple on the shelf.

Scott - I'd like one of the junction blocks at some point. Maybe at the show - if we get to have it. But for now I'm going to pull the trigger to the original isolator relay as well as the ring-tongue terminal to the wire to the key-on relay, put a screw through the two, and heat-shrink them.

Then, when I go to EFI I'll put the relay for the aux volt meter in the PDB, remove the original isolator relay, put the junction block there, and call it good.

Jim - As usual.

Bill - I'm using the '85 ground cable, which goes to the frame and then the block. But the trigger and positive wire run just as you described - under the mount and to the starter.

However, the '85 ground cable wasn't long enough to turn the battery, so the positive is out and negative is in.

And the "double fusible link to the large yellow wire to the PDC on the left side" is exactly the wire I have running from the battery side of the Megafuse on the passenger's side PDB over the radiator support to the smart battery isolator. But, when I go to EFI the PDB on the driver's side will be too far back for that wire to go all the way to it, so I'll probably have to have a jumper from the smart isolator to the PDB. Apparently either my passenger's side PDB is farther back or I took a longer route as the wire was just the right length to get to the smart isolator.

[Gary Lewis]

Scott - I'd like one of the junction blocks at some point. Maybe at the show - if we get to have it. But for now I'm going to pull the trigger to the original isolator relay as well as the ring-tongue terminal to the wire to the key-on relay, put a screw through the two, and heat-shrink them.

Then, when I go to EFI I'll put the relay for the aux volt meter in the PDB, remove the original isolator relay, put the junction block there, and call it good.

Jim - As usual.

Bill - I'm using the '85 ground cable, which goes to the frame and then the block. But the trigger and positive wire run just as you described - under the mount and to the starter.

However, the '85 ground cable wasn't long enough to turn the battery, so the positive is out and negative is in.

And the "double fusible link to the large yellow wire to the PDC on the left side" is exactly the wire I have running from the battery side of the Megafuse on the passenger's side PDB over the radiator support to the smart battery isolator. But, when I go to EFI the PDB on the driver's side will be too far back for that wire to go all the way to it, so I'll probably have to have a jumper from the smart isolator to the PDB. Apparently either my passenger's side PDB is farther back or I took a longer route as the wire was just the right length to get to the smart isolator.

The stainless clamps came in today, but I didn't like where they positioned the wire run across the radiator support, so I used these.

 

There were some holes in the support where I needed them, but where there wasn't a hole I added them and put 5 of them across there. Then I used two zip ties on each one, like this:

Then I moved on to making positive battery cables. Here's the main battery with its #2 positive cable. Other than clamping the battery down, that side is DONE! And, the horn even works.

And here's the aux battery with its #4 positive battery cable. (Turns out the big yellow wire coming across the radiator support is a #4, and that is the same stuff I used to make this cable.) Not that I have a Battery Tender attached to that battery. A few minutes after this pic was taken I heard the smart isolator click and the red LED on it came on. I watched as the voltage dropped from a bit above 13 volts to 12.9 as the charger struggled to bring the combined batteries up and hold the relay in. And, I checked between the two positive posts and initially saw 4.2mv, but it drifted down to under 1.0mv after a minute or so.

 

[Sac79]

The stainless clamps came in today, but I didn't like where they positioned the wire run across the radiator support, so I used these.

 

There were some holes in the support where I needed them, but where there wasn't a hole I added them and put 5 of them across there. Then I used two zip ties on each one, like this:

Then I moved on to making positive battery cables. Here's the main battery with its #2 positive cable. Other than clamping the battery down, that side is DONE! And, the horn even works.

And here's the aux battery with its #4 positive battery cable. (Turns out the big yellow wire coming across the radiator support is a #4, and that is the same stuff I used to make this cable.) Not that I have a Battery Tender attached to that battery. A few minutes after this pic was taken I heard the smart isolator click and the red LED on it came on. I watched as the voltage dropped from a bit above 13 volts to 12.9 as the charger struggled to bring the combined batteries up and hold the relay in. And, I checked between the two positive posts and initially saw 4.2mv, but it drifted down to under 1.0mv after a minute or so.

Looks professional to me...

[Gary Lewis]

Looks professional to me...

Thanks!

I need to secure the batteries. That'll be easy on the aux battery as I'll use the same system as before. But the main battery will be a different story. We shall see.

And while the electrical system is "hot", I need to work through the mess along the frame below the driver to see if I can find a problem in the Start circuit. I think I'll pull the power lead to the starter and listen for the relay in the starter to click when I turn the key. That way I can check everything but the starter itself w/o spinning the engine.

And at about that point I'll call the electrical system "done". Yes, there's more to do like wire in the relay and switch for the OX locker, set up the LED and switch for the smart battery isolator, etc. But those aren't needed for starting it.

[1986F150Six]

Looks professional to me...

And neat!

[Gary Lewis]

Looks professional to me...

And neat!

Thanks, guys. But I've run into a snag. As discussed on the Warning Buzzer thread, Big Blue's warning buzzer comes on when I open the door, long before placing the key in the ignition tumbler. In fact, apparently the column I installed doesn't even have the switch in the ignition tumbler. But something is triggering the buzzer.

So, I've been doing a bit of sleuthing and have realized that I may have a problem. It appears that an early column, meaning one w/o the key switch, an early C305A jumper for the speed control, and a 1985 wiring harness aren't fully compatible. I say that because I found these pinouts for C305 in the 1981 EVTM on the left and the 1985 on the right.

The key-on buzzer circuit is 158 BK/PK, which shows on the '85 diagram, but not on the '81. However, there are other changes as well. So, I'm going to create a spreadsheet to compare the circuits.....

[ArdWrknTrk]

Thanks, guys. But I've run into a snag. As discussed on the Warning Buzzer thread, Big Blue's warning buzzer comes on when I open the door, long before placing the key in the ignition tumbler. In fact, apparently the column I installed doesn't even have the switch in the ignition tumbler. But something is triggering the buzzer.

So, I've been doing a bit of sleuthing and have realized that I may have a problem. It appears that an early column, meaning one w/o the key switch, an early C305A jumper for the speed control, and a 1985 wiring harness aren't fully compatible. I say that because I found these pinouts for C305 in the 1981 EVTM on the left and the 1985 on the right.

The key-on buzzer circuit is 158 BK/PK, which shows on the '85 diagram, but not on the '81. However, there are other changes as well. So, I'm going to create a spreadsheet to compare the circuits.....

Only you, Gary.

Just keep being you.

It's precious. ❤️