El Chapo Posted February 9, 2022 Share Posted February 9, 2022 Recently acquired a 86 bronco xlt with 5.0 EFI automatic transmission. It’s a solid arizona only truck so no rust and otherwise in fantastic shape. So my frustration is that since it was parked for 10 years I decided to replace the entire full system including: tank, sending unit, high pressure pump, filter and inspected and replaced the donut filter in the fuel reservoir. I hope i put everything back correctly ha! Problem is that the pumps don’t click on so it doesn’t start, with external power source the pumps do click on but not with the ignition. I can’t find fuse link “S” to check or the fuel shut off / relay r for that matter anything else related to getting the fuel pumps going Link to comment Share on other sites More sharing options...
Gary Lewis Posted February 9, 2022 Share Posted February 9, 2022 Welcome! Glad you joined. Where's home? I ask because we have a map (Bullnose Forum/Member's Map in the menu) and we can add you with a city/state or zip. I look forward to seeing pics of your Bronco. As for your electrical problems, you really need to start a thread in the main section on that as it'll get more attention there than here. This folder is really just for introductions. So, would it be ok if I moved this to the main section? Meanwhile I'll attempt to answer your questions in my next post. Link to comment Share on other sites More sharing options...
Gary Lewis Posted February 9, 2022 Share Posted February 9, 2022 Welcome! Glad you joined. Where's home? I ask because we have a map (Bullnose Forum/Member's Map in the menu) and we can add you with a city/state or zip. I look forward to seeing pics of your Bronco. As for your electrical problems, you really need to start a thread in the main section on that as it'll get more attention there than here. This folder is really just for introductions. So, would it be ok if I moved this to the main section? Meanwhile I'll attempt to answer your questions in my next post. You are going to have to get very familiar with the 1986 EVTM - Electrical & Vacuum Troubleshooting Manual. It is a Ford document and is available here: Documentation/Electrical/EVTM's/1986 EVTM. Once going there you have to pick the section. In this case you need these sections: Electronic Engine Control: This gives you the schematics specific to the EEC system. Electric Fuel Pump Control: Schematics for the fuel pump's circuits, including on Page 107 an illustration showing where the fuel pump cutoff relay is - near the brake booster. But don't miss the inertia switch in the feed to the relay. It is near the passenger's left foot and if it trips there is no power to the pump, even if the relay works. Charge/Power Distribution: Shows the power circuits, and on Page 15 it shows that Fuse Link S attaches to the starter relay. Link to comment Share on other sites More sharing options...
mat in tn Posted February 9, 2022 Share Posted February 9, 2022 You are going to have to get very familiar with the 1986 EVTM - Electrical & Vacuum Troubleshooting Manual. It is a Ford document and is available here: Documentation/Electrical/EVTM's/1986 EVTM. Once going there you have to pick the section. In this case you need these sections: Electronic Engine Control: This gives you the schematics specific to the EEC system. Electric Fuel Pump Control: Schematics for the fuel pump's circuits, including on Page 107 an illustration showing where the fuel pump cutoff relay is - near the brake booster. But don't miss the inertia switch in the feed to the relay. It is near the passenger's left foot and if it trips there is no power to the pump, even if the relay works. Charge/Power Distribution: Shows the power circuits, and on Page 15 it shows that Fuse Link S attaches to the starter relay. maybe I picked up on something. maybe it's just a slip. did you replace a sending unit or a pump/sending unit? Link to comment Share on other sites More sharing options...
El Chapo Posted February 9, 2022 Author Share Posted February 9, 2022 Welcome! Glad you joined. Where's home? I ask because we have a map (Bullnose Forum/Member's Map in the menu) and we can add you with a city/state or zip. I look forward to seeing pics of your Bronco. As for your electrical problems, you really need to start a thread in the main section on that as it'll get more attention there than here. This folder is really just for introductions. So, would it be ok if I moved this to the main section? Meanwhile I'll attempt to answer your questions in my next post. Yes please move it to the main folder, I live in Phoenix Link to comment Share on other sites More sharing options...
Gary Lewis Posted February 9, 2022 Share Posted February 9, 2022 Yes please move it to the main folder, I live in Phoenix Moved and mapped. Link to comment Share on other sites More sharing options...
El Chapo Posted February 9, 2022 Author Share Posted February 9, 2022 maybe I picked up on something. maybe it's just a slip. did you replace a sending unit or a pump/sending unit? I did replace the sending unit in the new tank and the inline pressure pump, after it sat for so long the fuel in the old tank smelled like turpentine and the old sending unit was corroded severely. Link to comment Share on other sites More sharing options...
El Chapo Posted February 9, 2022 Author Share Posted February 9, 2022 You are going to have to get very familiar with the 1986 EVTM - Electrical & Vacuum Troubleshooting Manual. It is a Ford document and is available here: Documentation/Electrical/EVTM's/1986 EVTM. Once going there you have to pick the section. In this case you need these sections: Electronic Engine Control: This gives you the schematics specific to the EEC system. Electric Fuel Pump Control: Schematics for the fuel pump's circuits, including on Page 107 an illustration showing where the fuel pump cutoff relay is - near the brake booster. But don't miss the inertia switch in the feed to the relay. It is near the passenger's left foot and if it trips there is no power to the pump, even if the relay works. Charge/Power Distribution: Shows the power circuits, and on Page 15 it shows that Fuse Link S attaches to the starter relay. Yes thank you I have see that document it’s great but as a old beginner like me I still get confused as things don’t seem to match what’s on my truck, the previous owner claims nothing funky was ever done to it so should all make sense. I’ll send pictures Link to comment Share on other sites More sharing options...
Gary Lewis Posted February 9, 2022 Share Posted February 9, 2022 Yes thank you I have see that document it’s great but as a old beginner like me I still get confused as things don’t seem to match what’s on my truck, the previous owner claims nothing funky was ever done to it so should all make sense. I’ll send pictures When you post the pics you should walk through the Insert Image dialog instead of posting a link. That way the image is permanently part of this forum even if where you have it stored goes away. For instance, I just copied your link and pasted it into the line shown below, after wiping out the "http://" that is already in there. And I got this: Link to comment Share on other sites More sharing options...
mat in tn Posted February 10, 2022 Share Posted February 10, 2022 When you post the pics you should walk through the Insert Image dialog instead of posting a link. That way the image is permanently part of this forum even if where you have it stored goes away. For instance, I just copied your link and pasted it into the line shown below, after wiping out the "http://" that is already in there. And I got this: the sending unit in the picture is an in-tank pump/sending unit. it contains a priming pump to get fuel to the main line pump which will build pressure but not prime itself. did you install a new one with a pump? Link to comment Share on other sites More sharing options...
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