Mystery wires dangling on Mystery Vac Hose

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skysurfer

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Your first two pictures show the mystery green wire plugged in. Where does it go to on your truck?

I'm not seeing it. I have the grey connector with one green on the left side and two green on the right, but the op already has that. His photoshop is highlighting a different green wire just above the grey connector.
 

bucket

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I'm not seeing it. I have the grey connector with one green on the left side and two green on the right, but the op already has that. His photoshop is highlighting a different green wire just above the grey connector.

So it is!!

Ok, I know the mystery green wire now. That's the coolant temp sender wire for the factory gauge. That brittle/broken end goes onto the post on the sender.
 

BBBURB

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So it is!!

Ok, I know the mystery green wire now. That's the coolant temp sender wire for the factory gauge. That brittle/broken end goes onto the post on the sender.

OMG thank you bucket! I have been trying to find out why the coolant gauge has not been working for days. Where is the coolant sender located? I thought the coolant sender was under the thermostat, Ive unplugged the plug to the sensor under the thermostat several times and it had no affect on the gauge.
 

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OMG thank you bucket! I have been trying to find out why the coolant gauge has not been working for days. Where is the coolant sender located? I thought the coolant sender was under the thermostat, Ive unplugged the plug to the sensor under the thermostat several times and it had no affect on the gauge.


some were in the head, on passenger side, rear
 

BBBURB

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some were in the head, on passenger side, rear

Woa. I looked there on the passenger side head in the rear and there was this... is this it? I think this is it! Its so weird it only has one lil wire connector. This must be a grounding sensor that acts as a resistor.

You must be registered for see images attach
 

DoubleDingo

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I believe that is it... A little dirty so it'll need to be cleaned up
 

bucket

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Big blocks and heavy duty cooling were a little bit different because of the auxiliary fan. I "think" the one on the passenger side is for the fan and the sender on the driver side is for the gauge (that's normally how small blocks were setup too).
 

BBBURB

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Big blocks and heavy duty cooling were a little bit different because of the auxiliary fan. I "think" the one on the passenger side is for the fan and the sender on the driver side is for the gauge (that's normally how small blocks were setup too).

Thank you again bucket!!! I was able to verify by grounding green wire #1 (passenger side), the auxiliary fan turned on. When I grounded the green wire #4 (drivers side) to the body the Coolant gauge went to Hot.

Here is the updated list for this 454 7.4L:
  1. Auxiliary Fan
  2. test wire for fuel pump
  3. tachometer wire (not used)
  4. coolant gauge
  5. check valve feed for the cruise control? Maybe to the brake?
  6. plastic pcv hose to air cleaner(changed mine for a rubber hose and a plastic elbow)

I almost have everything completed. I just need to trace #5 (vacuum hose) and my list will be complete.
 
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dougbert

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Woa. I looked there on the passenger side head in the rear and there was this... is this it? I think this is it! Its so weird it only has one lil wire connector. This must be a grounding sensor that acts as a resistor.

You must be registered for see images attach


ok, you have a BBC, and I don't know them, but it looks like it and they are a single wire on the SBC
 

skysurfer

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  1. check valve feed for the cruise control? Maybe to the brake?
Is there any difference between BBC and SBC? My post on page 1 has every connection for SBC. Honestly don't know how I could have made it any more clear.
 

BBBURB

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Is there any difference between BBC and SBC? My post on page 1 has every connection for SBC. Honestly don't know how I could have made it any more clear.

skysurfer your photos are very clear and informative, thank you im very appreciative of that!!! I have yet to attempt to trace the vacuum hoses using your photos! I was stuck on the wires and now I am ready to start following the hoses using you images. Thank You! Ill see if i can get to it today! =) Ill update you soon.

Changes over last week:

Thermostat (Was missing)
ignition module
Distributor Cap & Rotor
PCV Valve & Hose , Breather Hose (Custom made)
TBI rebuild / kit
New Injectors
Replace blown fuses
 
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shiftpro

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Might take an inexperienced user much longer unfortunately.

Yes it would take me a fricken year to do that, and it would be a mess.
Fortunately I have several other skills..
 

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