Fixing a jimmy rigged electrical system

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jfrancom101

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Also I know it's not solved yet but I just eant to thank you. I can't beleive how resourcful and willing to help you all are. I sure do Appreciate it
 

SirRobyn0

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Yeah. Eventually would a mechanical pump be a lot better? I don't know what the pump plate is, but I'm definetly not used to deisel engines. It's nice being able to learn more
Well you should do something. The current fuel pump setup is poor. You'll need to decide what you prefer to do but basically the options will be going to a mechanical pump, or purchasing a high quality electric pump and mounting it back by the fuel tank, if you have two tanks then your pretty much stuck installing it after the tank valve, which means it's still got to suck fuel much further than it should, or replacing the tank valve with one that is designed to have pressure in it.

It seems to me that even when a high quality electric pump is installed, it seems like they still fail more frequently than the mechanical pumps.

Block off plate. So the mechanical pump would have been located on the block on the front passenger side. If the old pump was removed then something has to go over the hole in the block or oil pours out. So a block off plate is typically installed to cover the hole. Of course it's also possible that they just left the old dead pump bolted to the block. Give what I see with your wiring I wouldn't be surprised. Unfortunately it doesn't look like the former owners cared to much about it.

On the wiring. In your most recent set of pictures: First picture, do I see bare wires off the positive terminal by the washer bottle? If so that should be addressed. In your third picture that thing is a mess. Especially the wire on the left stud... That end is so far gone there is no way power goes though that thing properly. I would cut the ends off all of the wires that go on both of those terminals and crimp new eyelets on them and reinstall. Looks like one of the eyelets on the right stud is to big as well.

5th picture. Forget what I said about a fuel pump block off plate. If you look towards the exhaust manifold from the electric pump that thing attached to the block is the old dead mechanical pump. Man they just rigged that electric pump up right there next to the exhaust, once you get though the electrical stuff you really should address the fuel pump issue that is a break down looking for a place to happen.
 

WP29P4A

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Well you should do something. The current fuel pump setup is poor. You'll need to decide what you prefer to do but basically the options will be going to a mechanical pump, or purchasing a high quality electric pump and mounting it back by the fuel tank, if you have two tanks then your pretty much stuck installing it after the tank valve, which means it's still got to suck fuel much further than it should, or replacing the tank valve with one that is designed to have pressure in it.

It seems to me that even when a high quality electric pump is installed, it seems like they still fail more frequently than the mechanical pumps.

Block off plate. So the mechanical pump would have been located on the block on the front passenger side. If the old pump was removed then something has to go over the hole in the block or oil pours out. So a block off plate is typically installed to cover the hole. Of course it's also possible that they just left the old dead pump bolted to the block. Give what I see with your wiring I wouldn't be surprised. Unfortunately it doesn't look like the former owners cared to much about it.

On the wiring. In your most recent set of pictures: First picture, do I see bare wires off the positive terminal by the washer bottle? If so that should be addressed. In your third picture that thing is a mess. Especially the wire on the left stud... That end is so far gone there is no way power goes though that thing properly. I would cut the ends off all of the wires that go on both of those terminals and crimp new eyelets on them and reinstall. Looks like one of the eyelets on the right stud is to big as well.

5th picture. Forget what I said about a fuel pump block off plate. If you look towards the exhaust manifold from the electric pump that thing attached to the block is the old dead mechanical pump. Man they just rigged that electric pump up right there next to the exhaust, once you get though the electrical stuff you really should address the fuel pump issue that is a break down looking for a place to happen.
I am slow at typing, so I glad you typed what I was also thinking. Lots of poor connections that need to be corrected. I would be willing to bet based on his first post, if he worked on the carb and lost all power to crank and start, the odds are he bumped a lose wire and lost one of the marginal connections. I would use a test light that has a clip on the ground side, clip it to ground, stick the probe end in the red wire on the Dist, turn on the key, to run position. Then gently move some of the not so pretty connections and watch the test light, see if you can find a wire that will make the test light come on. If you can find the lose connection with that trick then you can get spark back and move forward with cleaning up the rest of the connections.

If he has a private jet like some of my clients I would be happy to help fly up and help fix the wiring.
 

jfrancom101

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Well you should do something. The current fuel pump setup is poor. You'll need to decide what you prefer to do but basically the options will be going to a mechanical pump, or purchasing a high quality electric pump and mounting it back by the fuel tank, if you have two tanks then your pretty much stuck installing it after the tank valve, which means it's still got to suck fuel much further than it should, or replacing the tank valve with one that is designed to have pressure in it.

It seems to me that even when a high quality electric pump is installed, it seems like they still fail more frequently than the mechanical pumps.

Block off plate. So the mechanical pump would have been located on the block on the front passenger side. If the old pump was removed then something has to go over the hole in the block or oil pours out. So a block off plate is typically installed to cover the hole. Of course it's also possible that they just left the old dead pump bolted to the block. Give what I see with your wiring I wouldn't be surprised. Unfortunately it doesn't look like the former owners cared to much about it.

On the wiring. In your most recent set of pictures: First picture, do I see bare wires off the positive terminal by the washer bottle? If so that should be addressed. In your third picture that thing is a mess. Especially the wire on the left stud... That end is so far gone there is no way power goes though that thing properly. I would cut the ends off all of the wires that go on both of those terminals and crimp new eyelets on them and reinstall. Looks like one of the eyelets on the right stud is to big as well.

5th picture. Forget what I said about a fuel pump block off plate. If you look towards the exhaust manifold from the electric pump that thing attached to the block is the old dead mechanical pump. Man they just rigged that electric pump up right there next to the exhaust, once you get though the electrical stuff you really should address the fuel pump issue that is a break down looking for a place to happen.
Haha, I was wondering what that extra oil filter looking thing was for. I guess that's probably the pump. Once I got the thing running sounds like I should jump on that pump next
Picture 1, The wires shown are black, I don't see any that are bare.
Picture three, I'll order a better crimping set. The one I got deals with smaller wires.
 

jfrancom101

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I am slow at typing, so I glad you typed what I was also thinking. Lots of poor connections that need to be corrected. I would be willing to bet based on his first post, if he worked on the carb and lost all power to crank and start, the odds are he bumped a lose wire and lost one of the marginal connections. I would use a test light that has a clip on the ground side, clip it to ground, stick the probe end in the red wire on the Dist, turn on the key, to run position. Then gently move some of the not so pretty connections and watch the test light, see if you can find a wire that will make the test light come on. If you can find the lose connection with that trick then you can get spark back and move forward with cleaning up the rest of the connections.

If he has a private jet like some of my clients I would be happy to help fly up and help fix the wiring.
I tested the wires going to the dist. The yellow one goes to through the firewall (I think I was wrong and that it is the yellow one that goes to the ignition but not sure. I follow the red wire and it goes into a a rather large wrap and all the wires come out connencting to what I have a picture of below. all the wires down there seem to have a pretty good connection but do to how many wires there are I didn't follow perfectly which one was the red that goes to the dist.

haha I wish I had a private jet
 

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jfrancom101

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Also I failed to mention earlier, the secondary battery has the main wires going to the plow, as well as the mess of wires to to the back engine.
 

Grit dog

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Yea, that's a terrible idea, and would never do that.

I really don't know how many amps that pump draws, but lets say for the sake of discussion that it's 5 amps, going to the one wire that powers the distributor. That one wire was never meant to power a motor, doing that is going to cause a voltage drop in the wiring to the distributor, so it's getting fed lower voltage than it should be.

The best way to wire an electric pump would be though a relay, second best would be a key on power off the fuse box.

Also in the current set up not only is it likely that the distributor is getting less voltage than it should, it's very likely that the fuel pump is seeing reduced voltage. Lower voltage to a motor, increases amp draw, increases heat, and shortens the life of the fuel pump.

Ya, I'd say that really needs to be sorted out properly.

@jfrancom101 so if it was converted to a gas 350, you should be able to run a factory mechanical fuel pump. I'm sure there is no push rod under the pump plate in the motor, so you'd need to get one of those, plus a pump. Then depending on the pump you choose possible a regulator. If you decide to convert to mechanical pump we can talk more about the options then.
Someone powered that little fuel pump with a scotch lock wire on the electric choke lead on my truck! Horrible idea, but fwiw it worked all summer (other than frying a couple pumps).
I wired it through a relay, ign on. But that was still unsafe as the pump obviously ran continuously with the key on (even if engine not running).
I just re-did that recently with a dedicated fuel pump relay with a primer timer. Runs 3 sec at key on and then shuts off until it sees a tach signal indicating the engine is spinning. If the OP is interested I posted it here recently.
 

Grit dog

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Haha, I was wondering what that extra oil filter looking thing was for. I guess that's probably the pump. Once I got the thing running sounds like I should jump on that pump next
Picture 1, The wires shown are black, I don't see any that are bare.
Picture three, I'll order a better crimping set. The one I got deals with smaller wires.
Sorry I'm not helping with your primary issue, but once you get it sorted, just put a new mechanical pump on it. Unless the cam lobe is wore out, it's a 1000% better solution for a carbureted engine.
 

WP29P4A

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Also I failed to mention earlier, the secondary battery has the main wires going to the plow, as well as the mess of wires to to the back engine.
Just to clarify, the truck has a snow plow on it? Also the sentence "as well as the mess of wires to the back engine" Back engine or back OF engine? You might be outside my experience if you have dual engines.
 

WP29P4A

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Haha, I was wondering what that extra oil filter looking thing was for. I guess that's probably the pump. Once I got the thing running sounds like I should jump on that pump next
Picture 1, The wires shown are black, I don't see any that are bare.
Picture three, I'll order a better crimping set. The one I got deals with smaller wires.
This is what I use, I prefer the naked butt splices and shrink wrap to keep everything clean. The connectors with the colored plastic insulators look crappy and don't crimp as well. One more tip, when you are replacing wires or connectors it is less confusing if you correct one wire at a time instead of pulling everything apart all at once. Start where ever you feel comfortable. If it's in your budget, a colored wiring diagram as reference will save you time and aggravation too. If you have the option of diesel diagram and regular, get both. That way one diagram shows what you have and the other shows where you want to end up. It will help you know what to remove and what needs to be changed.

The dual battery setup was to power the glow plugs on the diesel engine for starting, if you are going to use it as a spare battery it will be wired a little different than the diesel configuration. Or the second battery and the extra wiring can be removed.
 

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WP29P4A

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Just to clarify, the truck has a snow plow on it? Also the sentence "as well as the mess of wires to the back engine" Back engine or back OF engine? You might be outside my experience if you have dual engines.
I have always wanted to build a truck with the engine in the bed with a trans axle.
 

Turbo4whl

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Just to clarify, the truck has a snow plow on it? Also the sentence "as well as the mess of wires to the back engine" Back engine or back OF engine? You might be outside my experience if you have dual engines.
Salt spreader engine?
 

gotyourgoat

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So I'm attempting to get my truck running, 1985 2500. It was diesel, but converted over to a 5.7. When I fist bought it it needed some carb work, (It did start up but was running horribly) After doing the work all the sudden the key doesn't do anything.
Whoever switched it over tp a 5.7 jimmyrigged some of the wiring and I found a look wire(Blue in the picture) Following the blue wire it connects to a yellow which goes to the distributor, and a red which goes to the fuel pump. When the key did nothing I connected the loose wire to positive on the battery and the ignition lights came on, however it wasn't turning over. Any ideas as to where this wire should go? I couldn't find any loose wires, I wondered about the solenoid looking thing (Also shown in the picture) but when I connect to to the other bolt nothing happens.

Also quick note, the truck still has 2 batteries because it used to be a desiel
There is a mechanical fuel pump in these first pictures. What is it connected to and where are the fuel lines routed?? Is the electric pump PULLING from the tank or a gas can somewhere?

Please do nothing but remove that electric pump from the engine bay. If you intend to run electric that's fine but put it next to the tank. You may also need a pressure regulator with a carburetor setup and an electric pump.

If I had to guess this electric pump hacking setup was proof it could run so it could be sold... Now that we've done that let's put a mechanical pump on and get rid of the wiring that shouldn't be there and is only causing issues.
 

AuroraGirl

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He said plow setup, where the **** is the plow hydraulics pump if its electric? makes me wonder...

And yeah, what is meant by rear engine


I think we need more Pics lOL
For reference here is my pump setup on the right.
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