Loosing 12 volts at the injection pump now

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Dieselbrent

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I want to say thank you everyone for helping me on these problems in the past I have had and all the advice given. It's helped me alot. Currently I have the mechanical 6.5 diesel in the truck, but I am loosing 12 volts to the injection pump. The pump is brand new. Where does the 12 volts feed from? And has anyone ran into this problem. I'm scratching my head on this one. I hope yall can help me out.
 

Redfish

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I want to say thank you everyone for helping me on these problems in the past I have had and all the advice given. It's helped me alot. Currently I have the mechanical 6.5 diesel in the truck, but I am loosing 12 volts to the injection pump. The pump is brand new. Where does the 12 volts feed from? And has anyone ran into this problem. I'm scratching my head on this one. I hope yall can help me out.
Friend, it may help if you can go back and edit the Title of this thread. I was completely lost about how you lost 12 BOLTS. I am NOT making fun of you, I am just letting you know that you may get better help if we know it is an electrical problem.

I know there are some decent electrical schematics available on this forum and on Google as well.
 

Frankenchevy

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Did 6.5 diesels come in 88s from the factory? I didn’t think so…

If it’s a swap, the 12v came from wherever the guy who swapped it decided to pull 12v from. If this is the case, look in the lower left side of the fuse panel. That’s where accessory spots are located. Check there and look for a blown fuse. Also look at your ignition switch.
 

Dieselbrent

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The truck is original with the 6.2 diesel.
 

Dieselbrent

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The truck came originally with a 6.2, and I took it out replaced it and when I put the motor back in I started loosing 12 volts. I checked the fuses and they were good. Does the wire to the injection pump go to the ignition switch in the steering column? Thank you for helping
 

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Check the frame to battery (-) and block.
 

Originalthor

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If I remember correctly the 12 volts does come from the ignition switch unfused. Kinda like the coil does on a 5.7 tbi. I had problems with not getting a clean 12 volts to my coil and it was the ignition switch.

This is a ignition switch pulled apart. Pretty bad inside of there and burnt and corrosion. Cleaned it up and alot of my problems went away.
 

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Dieselbrent

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Found the problem. The electric air dog system wasn't turned up enough to give it enough fuel.
 

Rickf

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I'm afraid to ask but....WTF is an electric air dog system? Does it control the harmonic valves? Why can't I find it on any of my trucks?
 

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