Big Blue's Transformation

[Gary Lewis]

You could un-tang (?) the terminals from the connectors if needed but it does make it a more complex, intertwined harness. Plus with the size issue, sounds like there isn't really a benefit.

With that, I am back to wiring all the non-clock circuits directly to the switches with female 1/4s and if in the future you need to add a connector for whatever reason you can.

Yeah, I think I'll just use individual 1/4" connectors.

Didn't get very far on that today as I was fighting the gas leak problem. Finally put a vacuum cap over the end of the line that was dripping, and then for fear that the gas would kill the cap over night I put a hose over that, using the cap as an adapter to get from the 3/16" of the line to the 3/8" of the fuel hose I have. And I ran the line up to the passenger's door handle and secured it so it won't leak.

But then I kept smelling gas and discovered that the vapor hose-to-metal line connection at the tank was leaking. Put a hose clamp on that, and decided that the fumes in the shop were too much, so after wiping everything down and taking the wet paper towels outside I came into the house.

And now, knowing that the metal line is 3/16", I've ordered 10' of fuel hose that size. I think I'm going to run it from the wye up inside the bed's fender, and put a small fuel filter on the end. That way it'll be much higher than the tank and protected from things trying to get in. And later, if I want to put canisters on I won't have made it so I can't.

[Gary Lewis]

I don't know how the evap can siphon a tank.

The rollover valve is (and ends) right up in the grommet at the top.

But it will certainly drain any fuel left in the fill hose, and allow expanding fuel a route out.

Btw, does your later OBD system check for a sealed system, and would it throw a code (unless you turned it off in software)?

It's almost like you would want a check valve or solenoid on that vent, so it could vent negative pressure but not allow fumes to escape.

And in that respect having a charcoal canister really seems the kiss solution.

Ships/night.

I think that feature is turned off in my instance of EEC-V. At least that's my memory.

And perhaps it wasn't syphoning, but being the low point was just draining. However, when I took the spongy hose and wye off I got a steady stream out of the vent tube, which is why I sealed it for now. Which then shifted the leak to the hose coming off the tank.

As for the canister, it sits just above the frame and wouldn't be much higher than the tube I was playing with today. Obviously I overfilled the tank, but I don't want it going into the canister either.

[85lebaront2]

Well guys, I need some help. I don't have the charcoal canisters on the truck, nor any way to recover the vapors they'd gather. But today I discovered that I have a fuel leak that is coming from the vapor line and I need ideas on how to best deal with it.

The leak is at the wye where the two vapor lines merge, and at that point the lines are 2" below the bottom of the rear tank. It appears that I got the rear tank full enough that when the gas expanded in the warm shop it went down the vapor line and started a siphon.

I really don't want to run the charcoal canisters and don't want the switching valves that would let either the carb or the EFI vent them. So for now I've capped the line where it was to go into the wye. But, what's the best way to handle that? Should I run a line up high under the bed and put a fuel filter on it so varmints can't get it?

Thoughts?

And, for your humor, today it got cold enough for me to finally wear the coat I got last year, shown below. But when I started out to the shop I decided I didn't want to bring it out here 'cause I don't want it to absorb the smells. And then I opened the door and was struck with a strong gas smell from that leak.

Gary, if you have the same tank setup Darth has, my tank vent lines are 3/8" going to the dual canisters and a 1/4" (I think) going to the nearest frame crossmembers to the tanks. I found that the later trucks all have larger vent lines, probably to allow for the heating of the gas in the pumps and from the engine as it returns to the tank. If you are going to do away with the canisters, I would definitely recommend the later, larger vent lines. BTW, without the canisters, you are going to have gas fumes, especially in warm weather, and the HD (over 8500 GVW) system is no closed, it does vent to atmosphere at the rear and cab rear crossmembers.

 

[85lebaront2]

I don't know how the evap can siphon a tank.

The rollover valve is (and ends) right up in the grommet at the top.

But it will certainly drain any fuel left in the fill hose, and allow expanding fuel a route out.

Btw, does your later OBD system check for a sealed system, and would it throw a code (unless you turned it off in software)?

It's almost like you would want a check valve or solenoid on that vent, so it could vent negative pressure but not allow fumes to escape.

And in that respect having a charcoal canister really seems the kiss solution.

Jim. the OBD-II has two modes for EVAP. one is the pretty standard CANP valve, these in OBD-II usually have a small vacuum operated air pump that applies pressure to the tank(s) and pressure transducers in the tank(s) to measure this. If it doesn't see the pressure, it sets a code.

The second system uses what is called a VMV, or vapor management valve. This is teed into the line from the tank(s) to the canisters and is operated by manifold vacuum through a PWM solenoid valve, this adjusts the flow into the PCV line much as the carbureted snake's nest of hoses and valves did, except the snake's nest fed the canister vapors directly into the front 4 cylinders on the intake, the VMV feeds into the PCV line that goes to the rear of the plenum.

[Gary Lewis]

Gary, if you have the same tank setup Darth has, my tank vent lines are 3/8" going to the dual canisters and a 1/4" (I think) going to the nearest frame crossmembers to the tanks. I found that the later trucks all have larger vent lines, probably to allow for the heating of the gas in the pumps and from the engine as it returns to the tank. If you are going to do away with the canisters, I would definitely recommend the later, larger vent lines. BTW, without the canisters, you are going to have gas fumes, especially in warm weather, and the HD (over 8500 GVW) system is no closed, it does vent to atmosphere at the rear and cab rear crossmembers.

Bill - The steel lines ahead of the wye are 3/16" OD on Big Blue, as I measured them today with the nice Shars calipers on the Fractions setting. So that's why I bought the 3/16" hose. But, as I think about it, the lines after the wye could be larger.

As for fumes, I've not had canisters on Big Blue since I got him and the fumes haven't been bad at all, although that may be because I park him in a heated and cooled shop. So perhaps outside there would be more fumes, but then they would disperse more. So, maybe not a problem.

But you lost me - when did they go to venting to the atmosphere with a GVWR over 8500 lbs? Big Blue is rated at 8500 but it looks to me like he originally had canisters, plural. Don't know that for sure as they were long gone when I got the truck, but there's certainly the tubing going forward to just below the front of the bed where the two vent lines merge. Would they have done that if they were venting them?

[Gary Lewis]

Jim. the OBD-II has two modes for EVAP. one is the pretty standard CANP valve, these in OBD-II usually have a small vacuum operated air pump that applies pressure to the tank(s) and pressure transducers in the tank(s) to measure this. If it doesn't see the pressure, it sets a code.

The second system uses what is called a VMV, or vapor management valve. This is teed into the line from the tank(s) to the canisters and is operated by manifold vacuum through a PWM solenoid valve, this adjusts the flow into the PCV line much as the carbureted snake's nest of hoses and valves did, except the snake's nest fed the canister vapors directly into the front 4 cylinders on the intake, the VMV feeds into the PCV line that goes to the rear of the plenum.

Bill - So, the ECU doesn't know that it isn't controlling the vapor management valve? Its pulses just run off into the bit bucket?

[85lebaront2]

Bill - So, the ECU doesn't know that it isn't controlling the vapor management valve? Its pulses just run off into the bit bucket?

First, Darth had and still does have two canisters. I have a VMV on Darth as the Adam was never able to get the code for EVAP from coming on. The VMV is connected into the system so it will control the canister purge. You could either use a dummy load on the circuit or an extra solenoid valve to provide the required load for the EEC. It doesn't really have any sensor to monitor the flow unlike the CANP system that looks for a pressure sensor signal.

The over 8500 GVW trucks, even in the 1996 models did not have a sealed tank system, if you look at the picture of my front tank you can see the hose running across the frame.

[Gary Lewis]

First, Darth had and still does have two canisters. I have a VMV on Darth as the Adam was never able to get the code for EVAP from coming on. The VMV is connected into the system so it will control the canister purge. You could either use a dummy load on the circuit or an extra solenoid valve to provide the required load for the EEC. It doesn't really have any sensor to monitor the flow unlike the CANP system that looks for a pressure sensor signal.

The over 8500 GVW trucks, even in the 1996 models did not have a sealed tank system, if you look at the picture of my front tank you can see the hose running across the frame.

Ok, now I think I understand. Ford just vented the tanks. I'm happy to do that, and will probably do that at the tank rather than run it forward via the vent line and vent there. That way the little bitty 3/16" vent might be big enough to actually work.

On the VMV, if I get the code I'll probably put a dummy load on it.

Thanks!

[Gary Lewis]

Ok, now I think I understand. Ford just vented the tanks. I'm happy to do that, and will probably do that at the tank rather than run it forward via the vent line and vent there. That way the little bitty 3/16" vent might be big enough to actually work.

On the VMV, if I get the code I'll probably put a dummy load on it.

Thanks!

I got the hot lead to the inverter installed today, and a start on the ground lead. Here's the lead, the left one, connected to the aux power relay:

And here's part of the run under the rocker and into the cab via the grommet. But I'm not really done as I didn't have enough of the 5/8" rubber-covered clamps, but they'll be here tomorrow so I can finish this run.

Last, here are now-you-see-it and now-you-don't shots of the run inside the cab corner. Also, not visible is the extra grommet I put on the wire inside the corner, just in case I need it some day.

[grumpin]

I got the hot lead to the inverter installed today, and a start on the ground lead. Here's the lead, the left one, connected to the aux power relay:

And here's part of the run under the rocker and into the cab via the grommet. But I'm not really done as I didn't have enough of the 5/8" rubber-covered clamps, but they'll be here tomorrow so I can finish this run.

Last, here are now-you-see-it and now-you-don't shots of the run inside the cab corner. Also, not visible is the extra grommet I put on the wire inside the corner, just in case I need it some day.

Looking good! Well done!