EFI For Big Blue

[Gary Lewis]

Game, what game? I haven't watched the NFL since the Baltimore Colts left town in 1983.

The high pressure pump pigtail may be in that long harness I sent you, if it was off the neighbor's wrecked F150 supercab, if not it shouldn't be too hard to add. Diagram is in the 1986 EVTM.

On the 5ology kit, there was a young man on the 429/460 group on FB bought one of their kits and had a real nightmare getting it to work. Depending on the MAF they use, if it is the same design as the Ford ones, K&N filters will oil the sensor after a while and require cleaning it. I also am not a big fan of "hot air" intakes. That filter setup would require building a box around the element then ducting cold air to it. The factory system has a nice big duct from the left side behind the grille right to the filter box. Maybe for Dad's truck as a lot of things there are going to be custom made anyway.

Chris - Thanks for sharing that. I hadn't seen one of those. But, I'm with Bill - I don't like an oiled filter ahead of my MAF. I've not had problems with them as I've not run one, but have known people who have and they did have to clean the MAF.

Having said that, if I didn't have the factory setup I'd be very interested in an aftermarket air intake - even w/o the "cold" air intake that Bill mentioned. But I do have the rare factory unit, including the "cold air" intake, and will use it to get the coolest air I can in summer when the underhood temps soar with that 460 under there.

Bill - I'm not a big NFL fan, but we lived just out of Philly for 10 years and the opportunity to cheer on the Eagles can't be missed given their lack of good luck in the past. (Just like we did with the Cubbies after living in Chicago.)

Let me get this drawn up and see what I need to change in the way of wiring. Right now I'm not thinking there will be all that much.

[NotEnoughTrucks]

Yikes! This is complicated.

I agree that the changeover was in 1990 for the high-pressure in-tank pump as Huck had them. And, the pump has some form of valve in it to allow the fuel to return as the fuel lines from each tank, both supply and return, were just connected via a wye. Very simple, and as I think about it that arrangement is becoming more and more attractive.

I have a post about it here, and you can see the size of that pump/valve combo. In fact, as described, it looks like it would be possible to replace the later sending unit with the Bullnose unit. But the downside is that later, after I'm gone, it'll be almost impossible to repair that system. Who would you turn to in order to get a new sending unit grafted onto a replacement pump?

Ray - What valve are you suggesting?

Bill - What are you saying about the 1985.5-6 system? Are you saying that they replaced the motorized valve with something else?

I'm really struggling with how to do this. I don't mine, too much, getting into some wiring changes as they'll be one time and I'll leave a good schematic. But I want people to be able to get parts for it, and we all know that pumps and sending units are almost a given to go out.

So, what's the best approach for maintainability? I'm still thinking that the 85.5-6 5.0L in-tank pumps and sending units would be best as you can and hopefully will be able to buy them off the shelf. But, what is the best approach for switching the input to the HP pump and getting the return back to the right tank?

I'll agree with Bill that the best design would be as built for the 85/86.

Might be relevant to share my fuel tank story with my son's 86 Bronco a couple years back. He needed a new pump and tank. Spectra Premium seems to be the best source for this, so we ordered the parts in. Turns out there were two opening sizes and not a lot of explanation as to what was going on. F8C was the 2" opening and F8D was the 3 5/8" opening. Measured the old tank and found it was a 2" opening, so we ordered the F8C. Also ordered a fuel module SP2531H which is the complete pump and sender assembly. Turns out this product needed the 3 5/8" opening. No product available for the 2" opening except for a generic replacement pump SP1152 which needed to be installed on the original sender and outlet assembly. Also ordered a STR02 strainer as it would be required. Pump fit the original assembly just fine, but the strainer did not fit the pump. There was a generic strainer included with the pump hardware which did fit the pump, but was visibly different from the application. Several emails were exchanged with Spectra which did not produce any clear answers, but we ended up using the generic pump strainer and the assembly works well even to this day. Rebuilding the sender was a bit more complicated, but we managed to make it workable after scavenging parts from another tank.

Bottom line becomes parts availability. Clearly, exact replacements were not available. The best option would have been the F8D tank and the SP2531H fuel module, but that info was not clear. I mentioned the later FDM tanks as I have replaced these and the opening is even larger. Spectra does not offer a complete assembly for the Bronco, but it does offer complete tanks with pump and senders. I would expect the 92 and up tanks would offer the best long term parts availability, but the fuel lines become quite different because of the FDM's as opposed to the in tank lift pumps, dual function reservoir and frame mounted high pressure pump of the earlier models.

Link to the Spectra Premium catalog. http://ecat.spectrapremium.com/

[Gary Lewis]

I'll agree with Bill that the best design would be as built for the 85/86.

Might be relevant to share my fuel tank story with my son's 86 Bronco a couple years back. He needed a new pump and tank. Spectra Premium seems to be the best source for this, so we ordered the parts in. Turns out there were two opening sizes and not a lot of explanation as to what was going on. F8C was the 2" opening and F8D was the 3 5/8" opening. Measured the old tank and found it was a 2" opening, so we ordered the F8C. Also ordered a fuel module SP2531H which is the complete pump and sender assembly. Turns out this product needed the 3 5/8" opening. No product available for the 2" opening except for a generic replacement pump SP1152 which needed to be installed on the original sender and outlet assembly. Also ordered a STR02 strainer as it would be required. Pump fit the original assembly just fine, but the strainer did not fit the pump. There was a generic strainer included with the pump hardware which did fit the pump, but was visibly different from the application. Several emails were exchanged with Spectra which did not produce any clear answers, but we ended up using the generic pump strainer and the assembly works well even to this day. Rebuilding the sender was a bit more complicated, but we managed to make it workable after scavenging parts from another tank.

Bottom line becomes parts availability. Clearly, exact replacements were not available. The best option would have been the F8D tank and the SP2531H fuel module, but that info was not clear. I mentioned the later FDM tanks as I have replaced these and the opening is even larger. Spectra does not offer a complete assembly for the Bronco, but it does offer complete tanks with pump and senders. I would expect the 92 and up tanks would offer the best long term parts availability, but the fuel lines become quite different because of the FDM's as opposed to the in tank lift pumps, dual function reservoir and frame mounted high pressure pump of the earlier models.

Link to the Spectra Premium catalog. http://ecat.spectrapremium.com/

While I think we are in agreement that the cleanest approach would be to build it as an 85.5/86 302, that doesn't look like it is a good solution from the parts availability point of view. As shown below, the part number for the reservoir/switching valve is F1TZ 9B263-B, and according to our friends on FTE, as of about a year and a half ago there weren't any available. However, with a bit of searching there seems to be one or two here or there. But that doesn't seem like a good approach for longevity.

I'm bummed. And, open to suggestions.

[85lebaront2]

While I think we are in agreement that the cleanest approach would be to build it as an 85.5/86 302, that doesn't look like it is a good solution from the parts availability point of view. As shown below, the part number for the reservoir/switching valve is F1TZ 9B263-B, and according to our friends on FTE, as of about a year and a half ago there weren't any available. However, with a bit of searching there seems to be one or two here or there. But that doesn't seem like a good approach for longevity.

I'm bummed. And, open to suggestions.

Ok, you do have a front tank from the huck correct? What happened to the tank(s) from the F450? did Jim keep those? The 1990 up fuel system uses no reservoir or selector valve, each pump module with attached gauge sender has built in check valves and if you can find a set of the recall check valves that attach to the supply side of the pump module then you will have whet you need to prevent cross fueling.

If you can find a set of 1987 up filler necks they are easier to fill through than the 1980-86 ones. I would just start prowling junk yards to see what you can find, then maybe order new parts based on that. This will also let you see what size openings are on the tanks on Big Blue. Now you know why I bought Big Ugly, it was everything I needed except the 35" extension for the fuel lines and harness.

[NotEnoughTrucks]

While I think we are in agreement that the cleanest approach would be to build it as an 85.5/86 302, that doesn't look like it is a good solution from the parts availability point of view. As shown below, the part number for the reservoir/switching valve is F1TZ 9B263-B, and according to our friends on FTE, as of about a year and a half ago there weren't any available. However, with a bit of searching there seems to be one or two here or there. But that doesn't seem like a good approach for longevity.

I'm bummed. And, open to suggestions.

I think the gauge sender issue alone is enough reason to stick with the 85/86 tanks.

All of the tanks 80 through 96 will fit in your truck and I think the 92 to 96 tanks would be the best bet for longevity if you can find the means to modify the senders so the fuel gauge does not read backwards.

There also is the issue of fuel line connectors. The earlier tanks used a type of hairpin clip to hold the connectors together, but the 92 and up trucks use those spring retainer clips.

I think there is a Dorman kit that could be used to make up custom fuel lines or adapters.

Sorry, I'm just full of good news today!

[Gary Lewis]

I think the gauge sender issue alone is enough reason to stick with the 85/86 tanks.

All of the tanks 80 through 96 will fit in your truck and I think the 92 to 96 tanks would be the best bet for longevity if you can find the means to modify the senders so the fuel gauge does not read backwards.

There also is the issue of fuel line connectors. The earlier tanks used a type of hairpin clip to hold the connectors together, but the 92 and up trucks use those spring retainer clips.

I think there is a Dorman kit that could be used to make up custom fuel lines or adapters.

Sorry, I'm just full of good news today!

Bill - I have both tanks from Huck, and one good pump/sending unit. And I have the fuel lines. But, there are no external check valves on them, so tell me more about those check valves. But, the sending units won't work at all with the Bullnose gauges. As Ray pointed out, the resistance range is backwards. No go.

Ray - I do believe I can put the Bullnose sender on the later pump. But that will be fiddly and not something I expect any of my offspring to be able to do. And, we all know that sending units and pumps are notoriously faulty these days.

I really don't want anything fiddly to maintain. So, I'm thinking about four options:

• Valves: If I had 4 electrically-operated on/off valves, or two 2-way valves they could be driven by the tank selector switch and I could run the 85.5/86 in-tank and high-pressure pumps.

• Later fuel gauge in a Bullnose cluster. Bullnose is 10 ohms full and 73 ohms empty, while the '96 temp gauge, and therefore probably the '87+ fuel gauges, are 74 ohms full and 9.7 ohms empty. Essentially backwards. Could maybe Rocketman modify the gauge?

• Arduino: This is the one that I think has possibilities. I've asked my nephew if he could program an Arduino to run pulse-width modulation to effectively reverse things. I could pretty easily map the voltage that the Bullnose gauge "sees" at various points from Full to Empty and then a table could be created that, when averaged, gives those voltages. That way I can use the later pumps and sending units.

Thoughts?

 

[85lebaront2]

Bill - I have both tanks from Huck, and one good pump/sending unit. And I have the fuel lines. But, there are no external check valves on them, so tell me more about those check valves. But, the sending units won't work at all with the Bullnose gauges. As Ray pointed out, the resistance range is backwards. No go.

Ray - I do believe I can put the Bullnose sender on the later pump. But that will be fiddly and not something I expect any of my offspring to be able to do. And, we all know that sending units and pumps are notoriously faulty these days.

I really don't want anything fiddly to maintain. So, I'm thinking about four options:

• Valves: If I had 4 electrically-operated on/off valves, or two 2-way valves they could be driven by the tank selector switch and I could run the 85.5/86 in-tank and high-pressure pumps.

• Later fuel gauge in a Bullnose cluster. Bullnose is 10 ohms full and 73 ohms empty, while the '96 temp gauge, and therefore probably the '87+ fuel gauges, are 74 ohms full and 9.7 ohms empty. Essentially backwards. Could maybe Rocketman modify the gauge?

• Arduino: This is the one that I think has possibilities. I've asked my nephew if he could program an Arduino to run pulse-width modulation to effectively reverse things. I could pretty easily map the voltage that the Bullnose gauge "sees" at various points from Full to Empty and then a table could be created that, when averaged, gives those voltages. That way I can use the later pumps and sending units.

Thoughts?

Ok, the recall was in 1993 and covered 1990-1993 trucks with all gasoline engines. There are five, two of which are NHTS numbers, the other three being Ford numbers.

[Gary Lewis]

Ok, the recall was in 1993 and covered 1990-1993 trucks with all gasoline engines. There are five, two of which are NHTS numbers, the other three being Ford numbers.

Here are some pictures of the tanks on Darth with the bed off check valves are circled:

Front tank

Rear tank

Ok, my technical advisor says using an Arduino to do this will be easy. And then I'll need to figure out what to do with all the other I/O pins and all the unused cycles.

Seriously, this is looking good. A one-time effort that can be used by other Bullnose owners to solve a problem in a clean way. And the wiring is much more simple.

And, Bill, I see the check valves. So, what do they solve? And where do I get them?

[85lebaront2]

Ok, my technical advisor says using an Arduino to do this will be easy. And then I'll need to figure out what to do with all the other I/O pins and all the unused cycles.

Seriously, this is looking good. A one-time effort that can be used by other Bullnose owners to solve a problem in a clean way. And the wiring is much more simple.

And, Bill, I see the check valves. So, what do they solve? And where do I get them?

If you can look up the recall notices, it should give PNs, now whether you can still find them new is anyones guess. These were on Big Ugly when I bought him for parts.

[Gary Lewis]

If you can look up the recall notices, it should give PNs, now whether you can still find them new is anyones guess. These were on Big Ugly when I bought him for parts.

The TSB is now shown in TSB/Fuel Cross-Flow, and the parts are available from Amazon. But there's one part number for 1990 & 91, and another for 1992 & 93.

Will need to do some research as to how available the pumps are, but apparently things changed as of 1994, so I wonder if I should go with the later style pumps and bypass the TSB?