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Discussion Starter · #1 ·
Hi all. One of my Fords is a 1984 F-250 w/ a 7.5L. I bought it to tug or camper and fourwheelers/dirt bikes to the mountains and back all summer or as much as possible. First trip out it ran great until about 60 miles upriver from home. Started sputtering and backfiring intermittently and over heating. I limped it the other 50 miles to campsite and left it there while I took the wifes car back to grab the four core radiator and a direct drive flex fan I had because it seems to run great with no load. started back with everything and ended up calling in backup to come grab my camper and another to grab my truck because of the same issue. long story short... I found the main wiring harness on top of the intake manifold to have melted together. Upon further inspection I have more bare wires on the frame rail that were causing my intermittent tank selection problems prior to this. So I,m in dire need of a complete wiring diagram(s) for a 1984 F-250 XLT Lariat 7.5L with all wiring from bumper to bumper. Now I have no tail lights, no dash lights, front tank returns into rear and headlights will only stay on for about 5 minutes and then go dead. So I am starting from scratch with this motor or my built 429 out of my 72 factory high boy custom. Either way I need your help Please.
 

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Hi all. One of my Fords is a 1984 F-250 w/ a 7.5L. I bought it to tug or camper and fourwheelers/dirt bikes to the mountains and back all summer or as much as possible. First trip out it ran great until about 60 miles upriver from home. Started sputtering and backfiring intermittently and over heating. I limped it the other 50 miles to campsite and left it there while I took the wifes car back to grab the four core radiator and a direct drive flex fan I had because it seems to run great with no load. started back with everything and ended up calling in backup to come grab my camper and another to grab my truck because of the same issue. long story short... I found the main wiring harness on top of the intake manifold to have melted together. Upon further inspection I have more bare wires on the frame rail that were causing my intermittent tank selection problems prior to this. So I,m in dire need of a complete wiring diagram(s) for a 1984 F-250 XLT Lariat 7.5L with all wiring from bumper to bumper. Now I have no tail lights, no dash lights, front tank returns into rear and headlights will only stay on for about 5 minutes and then go dead. So I am starting from scratch with this motor or my built 429 out of my 72 factory high boy custom. Either way I need your help Please.
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Discussion Starter · #4 ·
Thanks Action & Dominic. I appreciate you guys taking the time to forward these links to me. I feel that there really is not much to an 84 lariat. I'd just hate to pay $30 for another manual collecting dust when a couple diagrams would suffice for my project. I ran the main loom since I posted that and was hoping for a couple diagrams to reference. I have the dual tank transfer switch figured out with the help of a diagram I found a few weeks back on the web. After that towards the rear all I have is the run/stop/turn/trailerbrakes/12v+/reverse lights/ground from batt. And I ran a copper sheilded in case of back-up cams for truck and trailer. On board 12 volt compressors for each set of lift bags with electric pressure sensors ran to gages in cab next to control switchesthat operate the relays. I'm ditching all the smog crap to simplify system with less things to go wrong out in the middle of nowhere, with no cell or cb service/traffic the air bag system can completely fail and I still have the HD F-250 suspension that has always been the best for tugging and overloading the crap out of it. Only thing I'll drive. No disrespect but I'll try somewhete else for a couple diagrams so I can get back to camping by the coming weekend. Weather pack connectors and the rest of the loom is supposed to arrive by 9 pm tonight so I can start some crimping. Thanks again
 

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Your truck, your fix.

That shop manual likely costs less than half a tank of gas and may save you hours in figuring out how to correctly re-wire.

As to removing "smog crap", you may succeed in causing the engine to run poorly at times if not most of the time. The engine was designed for those parts to work with it. The 460 (7.5l) engine of 1968 to 1971 is not the same as your 1984 engine. By the time 1984 rolled around the compression was reduced, the block deck height had changed and the basic cylinder heads/valves had changed three times. Along with cam shaft/crankshaft changes that engine isn't the same as the 460 with out those parts.

And again it is your truck. Good luck

Action
 
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