Big Blue's Transformation

[Gary Lewis]

2.5V !?!?

Even though it's had that much time to recover, being disconnected from the tender.

Offff, that's got to be hard to come back from, for a starting battery!

And that one is an expensive monster.

I think your truck has an ON position and a RUN position... as was pointed out to me when someone had to change their lock cylinder recently.

So, maybe a little wiring correction is in order?

Better to find out these little issues now.

Yes, it is an expensive battery. I sure hope it comes back. But it had to have been the Battery Tender, so those little wires had to have just been pulling a small current continuously.

On as opposed to Run? Interesting. I had assumed that On brought everything on.

As for a wiring correction, I'm hoping that the wiring is good if it just gets 12v. But something isn't quite right about the fuel pump. The relay came in but the pump didn't. Oh well, I've been all over those circuits of late, so I can figure it out. Tomorrow, I hope!

[Gary Lewis]

Yes, it is an expensive battery. I sure hope it comes back. But it had to have been the Battery Tender, so those little wires had to have just been pulling a small current continuously.

On as opposed to Run? Interesting. I had assumed that On brought everything on.

As for a wiring correction, I'm hoping that the wiring is good if it just gets 12v. But something isn't quite right about the fuel pump. The relay came in but the pump didn't. Oh well, I've been all over those circuits of late, so I can figure it out. Tomorrow, I hope!

Mid-day report. The battery is coming up nicely, having been on the 10 amp setting on the charger now for maybe 20 hours it is now up to about 12.4 volts. So there's hope it isn't hurt too badly.

Given that I started testing, and now the sender unit relay works. I get almost 7/8 tank on the rear, which is dry, and the 7/16 on the front which has 5 gallons.

But jumpering the oil pressure switch wouldn't bring the pump on, so I checked the pump relay - no juice to the power side of it, although it was being pulled in. Next stop was the inertia switch - nothing in or out. So, off to the schematic on the PDB. Hmmm, Fuse #1 powers the fuel pumps, but there's no fuse in that position. Great! Put a fuse in and nada. Nothing at the inertia switch, which is a direct feed in theory from the PDB. And the fuse is good.

So, I guess I tear into the wiring of the PDB.

[1986F150Six]

Mid-day report. The battery is coming up nicely, having been on the 10 amp setting on the charger now for maybe 20 hours it is now up to about 12.4 volts. So there's hope it isn't hurt too badly.

Given that I started testing, and now the sender unit relay works. I get almost 7/8 tank on the rear, which is dry, and the 7/16 on the front which has 5 gallons.

But jumpering the oil pressure switch wouldn't bring the pump on, so I checked the pump relay - no juice to the power side of it, although it was being pulled in. Next stop was the inertia switch - nothing in or out. So, off to the schematic on the PDB. Hmmm, Fuse #1 powers the fuel pumps, but there's no fuse in that position. Great! Put a fuse in and nada. Nothing at the inertia switch, which is a direct feed in theory from the PDB. And the fuse is good.

So, I guess I tear into the wiring of the PDB.

You can do it, Gary!

[Gary Lewis]

You can do it, Gary!

Thanks, David. I need that encouragement. It is a bummer having to disassemble things that are "done" to find the error.

[Gary Lewis]

Thanks, David. I need that encouragement. It is a bummer having to disassemble things that are "done" to find the error.

Success!!!!!!!!! It was just a connector that wasn't fully seated! Now when I jumper the oil pressure switch I hear the pump run and see pressure coming up on the gauge. It is a bit high so I need to lower it to ensure the Edelbrock doesn't flood. But, IT WORKS!!!!

[ArdWrknTrk]

Success!!!!!!!!! It was just a connector that wasn't fully seated! Now when I jumper the oil pressure switch I hear the pump run and see pressure coming up on the gauge. It is a bit high so I need to lower it to ensure the Edelbrock doesn't flood. But, IT WORKS!!!!

Progress is good!

Once again, I'm glad you've found a simple fix.

[Gary Lewis]

Progress is good! :nabble_smiley_good:Once again, I'm glad you've found a simple fix.

Yes, progress is good. And today I took two steps forward - the fuse and the connector. But, I took a step back on the fuel pressure regulator - and I have a question for y'all in a bit.

 

As said, the pressure was a tad high. Like above 10 psi and headed for the moon. So I pulled out the instructions Holley sent and they were the wrong ones. Found the right ones on the internet, but they didn't really tell which ports to use. So I called tech support and waited on hold for 20 minutes with an irritating song looping every 30 seconds.

 

But, it turns out that I had it plumbed incorrectly. According to the tech "the center outlet is always the return regardless of brand". So I swapped the hoses around, which is FAR harder to do than to type. No joy. As you can see in the pic below, the pressure is at 11 psi and it would be far higher if I'd left the power on longer. And if you'll notice the adjusting screw is out so far it isn't touching anything, and the instructions awa their video say screwing it in raises the pressure.

 

So, it seems to me like I have one of two problems:

 

1. I have the supply and return lines from the pumps backwards. Big Blue's in-tank pump has the outlet/supply connection as 3/8" and the return as 5/16". And I assumed that this convention would be carried through on the EFI fuel delivery assemblies, although I can't really tell from the ones I have which is supply or return. But I used 3/8" as supply and 5/16" as return.

 

The regulator is bad.

 

I can swap the hoses and see if that fixes the problem. While that is a huge pain as these hoses don't like to come off the barbs, it would be less of a pain than returning the regulator only to find the next one does the same thing. But if that's the case then the fuel filter will be in the return rather than in the supply. I can just turn it around and it'll be fine, but I'll be filtering after the fact.

 

And, I just thought of a fairly simple test - once the pressure has dropped pull the filter and bring the pump on BRIEFLY. That should tell me which way the fuel is flowing.

 

Anyway, HELP!

 

[ArdWrknTrk]

Yes, progress is good. And today I took two steps forward - the fuse and the connector. But, I took a step back on the fuel pressure regulator - and I have a question for y'all in a bit.

 

As said, the pressure was a tad high. Like above 10 psi and headed for the moon. So I pulled out the instructions Holley sent and they were the wrong ones. Found the right ones on the internet, but they didn't really tell which ports to use. So I called tech support and waited on hold for 20 minutes with an irritating song looping every 30 seconds.

 

But, it turns out that I had it plumbed incorrectly. According to the tech "the center outlet is always the return regardless of brand". So I swapped the hoses around, which is FAR harder to do than to type. No joy. As you can see in the pic below, the pressure is at 11 psi and it would be far higher if I'd left the power on longer. And if you'll notice the adjusting screw is out so far it isn't touching anything, and the instructions awa their video say screwing it in raises the pressure.

 

So, it seems to me like I have one of two problems:

 

1. I have the supply and return lines from the pumps backwards. Big Blue's in-tank pump has the outlet/supply connection as 3/8" and the return as 5/16". And I assumed that this convention would be carried through on the EFI fuel delivery assemblies, although I can't really tell from the ones I have which is supply or return. But I used 3/8" as supply and 5/16" as return.

 

The regulator is bad.

 

I can swap the hoses and see if that fixes the problem. While that is a huge pain as these hoses don't like to come off the barbs, it would be less of a pain than returning the regulator only to find the next one does the same thing. But if that's the case then the fuel filter will be in the return rather than in the supply. I can just turn it around and it'll be fine, but I'll be filtering after the fact.

 

And, I just thought of a fairly simple test - once the pressure has dropped pull the filter and bring the pump on BRIEFLY. That should tell me which way the fuel is flowing.

 

Anyway, HELP!

 

You also have low pressure air, as shown with your brake bleeder.It's probably a lot safer than gasoline.

[85lebaront2]

Yes, progress is good. And today I took two steps forward - the fuse and the connector. But, I took a step back on the fuel pressure regulator - and I have a question for y'all in a bit.

 

As said, the pressure was a tad high. Like above 10 psi and headed for the moon. So I pulled out the instructions Holley sent and they were the wrong ones. Found the right ones on the internet, but they didn't really tell which ports to use. So I called tech support and waited on hold for 20 minutes with an irritating song looping every 30 seconds.

 

But, it turns out that I had it plumbed incorrectly. According to the tech "the center outlet is always the return regardless of brand". So I swapped the hoses around, which is FAR harder to do than to type. No joy. As you can see in the pic below, the pressure is at 11 psi and it would be far higher if I'd left the power on longer. And if you'll notice the adjusting screw is out so far it isn't touching anything, and the instructions awa their video say screwing it in raises the pressure.

 

So, it seems to me like I have one of two problems:

 

1. I have the supply and return lines from the pumps backwards. Big Blue's in-tank pump has the outlet/supply connection as 3/8" and the return as 5/16". And I assumed that this convention would be carried through on the EFI fuel delivery assemblies, although I can't really tell from the ones I have which is supply or return. But I used 3/8" as supply and 5/16" as return.

 

The regulator is bad.

 

I can swap the hoses and see if that fixes the problem. While that is a huge pain as these hoses don't like to come off the barbs, it would be less of a pain than returning the regulator only to find the next one does the same thing. But if that's the case then the fuel filter will be in the return rather than in the supply. I can just turn it around and it'll be fine, but I'll be filtering after the fact.

 

And, I just thought of a fairly simple test - once the pressure has dropped pull the filter and bring the pump on BRIEFLY. That should tell me which way the fuel is flowing.

 

Anyway, HELP!

 

Disconnect the return line from the regulator and plug the end for safety. Connect an extra piece of hose to the regulator output and run it around to the filler neck of the tank you are using. First if no fuel comes from the regulator you have determined you are plumbed backwards. If it does and you can now control the pressure then something is restricting the return, possibly the shuttle valve in the pump module. Does the pump module you are using still have the recall valve on it? That will guarantee that the flow direction is out from the tank leaving the other nipple as the return. I would also try low pressure air into the tank return to make sure it isn't obstructed. For a refresher, here are the two pictures of the 1993 FDM.

[Gary Lewis]

You also have low pressure air, as shown with your brake bleeder.

It's probably a lot safer than gasoline.

Are you saying to pressurize the tank via the cap or the vent and see where it comes out? Would the fuel delivery assembly work that way?

I was thinking I'd pull the fuel filter, which is easily done via the disconnects, and wrap the end of the lines in shop towels. Turn the pump on briefly and see which one gets wet. If it is what I thought was coming from the tank then I had the supply sussed correctly. If it is the one coming from the regulator then I have them backward.

Won't get to this until Sunday as we are going to a funeral tomorrow. But wouldn't that be a positive answer to the question? And not likely to get gas everywhere?