mat in tn Posted February 10, 2022 Share Posted February 10, 2022 Does this wire that should be connected to the “I” terminal have the diode on it as well? Last night I moved the blue fuseable link with the diode to the “I” terminal and there was no change in starting it was a pain to get going I had to manually fill the bowls with some gas until it picked up fuel. I swapped the relay with a spare I had that may also be questionable. The wiring is hacked in this truck there is a 5 pin relay in the fuel cutoff (relay without the resistance wire) with one of the wires clipped off that’s another potential issue I have seen I’m not sure which wire it is but I will check when I’m home. Overall same issue pain to get running but once it picked up fuel it drove fine. could this be something as simple as not enough oil pressure due to oil being too thick from the cold. you said it goes away after warming up. another possibility is a clogged fuel filter. made worse by the cold Link to comment Share on other sites More sharing options...
jmadigan Posted February 10, 2022 Author Share Posted February 10, 2022 could this be something as simple as not enough oil pressure due to oil being too thick from the cold. you said it goes away after warming up. another possibility is a clogged fuel filter. made worse by the cold I thought about that I was using rotella t4 to keep the cam alive but I switch to 5w30 to see if that was it. The oil pressure gauge comes right up I’m not sure how much oil pressure is there though. Also I have the Wix 30033 filter so I can see in there and there is no movement of fuel until it finally picks up. Link to comment Share on other sites More sharing options...
mat in tn Posted February 10, 2022 Share Posted February 10, 2022 I thought about that I was using rotella t4 to keep the cam alive but I switch to 5w30 to see if that was it. The oil pressure gauge comes right up I’m not sure how much oil pressure is there though. Also I have the Wix 30033 filter so I can see in there and there is no movement of fuel until it finally picks up. an in-tank pump is always primed. as long as there is gas in the tank. it does not need to pick up. either it's not running or its not flowing. does the system have a return line? If so, that should eliminate head pressure from stopping flow. Link to comment Share on other sites More sharing options...
85lebaront2 Posted February 10, 2022 Share Posted February 10, 2022 Does this wire that should be connected to the “I” terminal have the diode on it as well? Last night I moved the blue fuseable link with the diode to the “I” terminal and there was no change in starting it was a pain to get going I had to manually fill the bowls with some gas until it picked up fuel. I swapped the relay with a spare I had that may also be questionable. The wiring is hacked in this truck there is a 5 pin relay in the fuel cutoff (relay without the resistance wire) with one of the wires clipped off that’s another potential issue I have seen I’m not sure which wire it is but I will check when I’m home. Overall same issue pain to get running but once it picked up fuel it drove fine. The diode is in the pink with black hash wire originally, it is beyond the fusible link and may be in a "bulge" in the actual wire. If it is open then the priming function won't work, the pump will not run until the oil pressure switch closes. Please, those of you who are not familiar with a 460 "hot fuel handling package" refrain from interjecting comments. The system is confusing enough, compounded by (a) Ford changing it almost yearly during it's run and (b) trying to figure out what has been done in 39 years of different owners and shops working on it. Here is the wiring I removed from Darth when I converted to EFI. This is from the starter relay around, down the left valve cover and over to the fuel pump cutoff relay. Mine did not use the tank selector relay as it is a 1986 system. Link to comment Share on other sites More sharing options...
85lebaront2 Posted February 10, 2022 Share Posted February 10, 2022 an in-tank pump is always primed. as long as there is gas in the tank. it does not need to pick up. either it's not running or its not flowing. does the system have a return line? If so, that should eliminate head pressure from stopping flow. Pumps are, but the carburetor may not be, fuel evaporates from heat when sitting, and Holley carbs were known to leak at the cork gaskets. Link to comment Share on other sites More sharing options...
jmadigan Posted February 10, 2022 Author Share Posted February 10, 2022 The diode is in the pink with black hash wire originally, it is beyond the fusible link and may be in a "bulge" in the actual wire. If it is open then the priming function won't work, the pump will not run until the oil pressure switch closes. Please, those of you who are not familiar with a 460 "hot fuel handling package" refrain from interjecting comments. The system is confusing enough, compounded by (a) Ford changing it almost yearly during it's run and (b) trying to figure out what has been done in 39 years of different owners and shops working on it. Here is the wiring I removed from Darth when I converted to EFI. This is from the starter relay around, down the left valve cover and over to the fuel pump cutoff relay. Mine did not use the tank selector relay as it is a 1986 system. The wire i moved to the I position is the wire you labled "blue fusable link" it connects to the pink black hash wire. Also for those of you asking the carburetor is not losing fuel I have sight glasses the carb is full but when running it drains until i fill it by cranking and eventually it will fill on its own. So I'm loosing prime in the line. There is a return line hooked to the hot start canister. The fuel system is working as it should except for priming the carb when starting. It sounds to me like i need to test the Blue fusable link and the relay system am i correct? Link to comment Share on other sites More sharing options...
85lebaront2 Posted February 10, 2022 Share Posted February 10, 2022 The wire i moved to the I position is the wire you labled "blue fusable link" it connects to the pink black hash wire. Also for those of you asking the carburetor is not losing fuel I have sight glasses the carb is full but when running it drains until i fill it by cranking and eventually it will fill on its own. So I'm loosing prime in the line. There is a return line hooked to the hot start canister. The fuel system is working as it should except for priming the carb when starting. It sounds to me like i need to test the Blue fusable link and the relay system am i correct? Yes sir, that is correct. Are you comfortable following a wiring diagram? I posted them earlier, it is in two parts, one follows the gauge system wiring, the other the fuel pump power. If you unplug the yellow wires at C144 with the blue fusible link still on the hot side of the starter relay, there should be battery voltage there. If not then there is a problem with the fusible link. Look for a melted area and gently tug on the ends. If there is a melted area, that's the problem. If you have battery voltage there, try jumping the pins in the male side of C144 and see if you hear a pump run and a hiss from the vapor separator. If that works, then go under the passenger side of the dash, on the heater duct, you should see two yellow wires plugged into a switch with a push button on top, push down on the button and see if it clicks and stays down. If jumping the pins in C144 doesn't work, then move over to the relay under the shield on the driver's side firewall. Check first for battery voltage at the pink with black hash wire, this is the feed from the blue fusible link. If you have battery voltage there with the relay plugged in, then you will need to check for battery voltage at the yellow wire first, then the red and the brown with white wires, one should have power, if not the relay is bad. If you do not have power at the pink with black hash wire, then the diode may be open or the wire may be broken. If you find the tank selector relay is bad, a standard Bosch cube relay will functionally replace it with a socket. If it is exposed under hood, seal the back side of the socket with RTV. Link to comment Share on other sites More sharing options...
jmadigan Posted February 11, 2022 Author Share Posted February 11, 2022 Yes sir, that is correct. Are you comfortable following a wiring diagram? I posted them earlier, it is in two parts, one follows the gauge system wiring, the other the fuel pump power. If you unplug the yellow wires at C144 with the blue fusible link still on the hot side of the starter relay, there should be battery voltage there. If not then there is a problem with the fusible link. Look for a melted area and gently tug on the ends. If there is a melted area, that's the problem. If you have battery voltage there, try jumping the pins in the male side of C144 and see if you hear a pump run and a hiss from the vapor separator. If that works, then go under the passenger side of the dash, on the heater duct, you should see two yellow wires plugged into a switch with a push button on top, push down on the button and see if it clicks and stays down. If jumping the pins in C144 doesn't work, then move over to the relay under the shield on the driver's side firewall. Check first for battery voltage at the pink with black hash wire, this is the feed from the blue fusible link. If you have battery voltage there with the relay plugged in, then you will need to check for battery voltage at the yellow wire first, then the red and the brown with white wires, one should have power, if not the relay is bad. If you do not have power at the pink with black hash wire, then the diode may be open or the wire may be broken. If you find the tank selector relay is bad, a standard Bosch cube relay will functionally replace it with a socket. If it is exposed under hood, seal the back side of the socket with RTV. I can follow the diagram. I will check this all tonight when i get home and report back. You wouldnt happen to have the part numbers for the bosche relay would you? Also there is one thing i should mention erlier this summer the green connector on my fuel pump relay has a break in the yellow wire inside the pigtail. I went to the junkyard and got a new one and spliced it in place because i could not for the life of me de-pin the pigtail. So needless to say I shortened the resistance wire by about an inch which i know your not supposed to splice that wire could this be another issue? Link to comment Share on other sites More sharing options...
85lebaront2 Posted February 11, 2022 Share Posted February 11, 2022 I can follow the diagram. I will check this all tonight when i get home and report back. You wouldnt happen to have the part numbers for the bosche relay would you? Also there is one thing i should mention erlier this summer the green connector on my fuel pump relay has a break in the yellow wire inside the pigtail. I went to the junkyard and got a new one and spliced it in place because i could not for the life of me de-pin the pigtail. So needless to say I shortened the resistance wire by about an inch which i know your not supposed to splice that wire could this be another issue? Yellow doesn't matter, it is not resistance. I wish I had known, I just disassembled a green and a brown Ford relay plug from an EFI truck, but they are the same. To remove the wires, first carefully remove the red locking cover, then at each wire, where the tabs on the cover inserted, there is a plastic latch, carefully push it away to the edge of the slot, the wire should pull out from the bottom. The Bosch relay is what is called a mini cube relay, they are used by just about everybody, they have 5 pins roughly 1/4" wide laid out with the two coil pins on the sides, the center contact on one end and the NC and NO contacts opposite. The Bosch numbers for the terminals are: 30 common; 85, 86 coil; 87 NO, 87a NC. Here is a not super picture, this is a Chrysler one with a skirt for underhood use and it takes a latching socket: Link to comment Share on other sites More sharing options...
jmadigan Posted February 11, 2022 Author Share Posted February 11, 2022 Yellow doesn't matter, it is not resistance. I wish I had known, I just disassembled a green and a brown Ford relay plug from an EFI truck, but they are the same. To remove the wires, first carefully remove the red locking cover, then at each wire, where the tabs on the cover inserted, there is a plastic latch, carefully push it away to the edge of the slot, the wire should pull out from the bottom. The Bosch relay is what is called a mini cube relay, they are used by just about everybody, they have 5 pins roughly 1/4" wide laid out with the two coil pins on the sides, the center contact on one end and the NC and NO contacts opposite. The Bosch numbers for the terminals are: 30 common; 85, 86 coil; 87 NO, 87a NC. Here is a not super picture, this is a Chrysler one with a skirt for underhood use and it takes a latching socket: Okay ill look for a bosche relay. But what i mean by cutting the resistance wire is i spliced in an entire socket so every wire was shortened about an inch including the pink and black resistance wire Link to comment Share on other sites More sharing options...
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