87 Glow plug controller not getting Power! Run new hot wire?!?!

[Thefarmboy21]

I'm not getting any voltage at all to my GP controller on my 87 6.9. There is a mystery wire off my solenoid that has constant voltage even if the key is OFF. It looks like it was running to the GP controller before I pulled the motor. Also the original power wire was zip tied back but I thought I did it or something. SOOOOOO....is it ok to run constant voltage to the GP controller or should I do it differently? Also should I unhook the original wire or just use both wires? Thanks.

 

[Wyreth]

yes, the GPC needs constant hot.

Originally it should have had two 10gage wires supplying it with power. Note these are not truly sufficient, and it cannot hurt to upgrade to larger wires. Also check on the plug these wires come from by the solenoid on the passenger side. That plug likes to melt down as well.

 

[Thefarmboy21]

Ok well I think this is where my mystery wires go. It's two 10 gauge wires into one eyelet coming from constant hot on the passenger solenoid. Ok so now, do I still use the original wires or just unhook those all together to make sure it doesn't short?

 

[OLDBULL8]

Those two orange wires that come from the starter solenoid then go thru a connector then to the GP controller are fed from the battery with two fusible link wires connected at the solenoid. It doesn't do any good to increase the wire size, unless you increase the fusible link size. Fusible links are a safety, connecting a larger "AWG" wire direct to the battery could possibly cause a fire if the GP relay and/or wire short out. Just remember, you have almost unlimited current from a battery. Ya just don't wanna have that happen.

Edit: That connector melts because the connection becomes corroded (acts like a resister) and gets hot from the hi current. The GPC shouldn't be ON for more than 15 seconds max, If it's manually controlled by a push button, you can or could exceed that time. If the GPC relay would stick closed then you would have that situation where the current is constantly fed to the GP's.

 

[Thefarmboy21]

The wires that are. Coming straight from the solenoid ARE Fusable links. They look just like the factory wires but are not. Tho they may have come from another international or something. They come off the hot side of the solenoid and I think are supposed to go to my GP controller. So, my GP controller would be getting constant voltage to the post. It will NOT be connected in any way to a manual controller. Just constant voltage to the factory GP controller. Does this sound correct?

 

[Thefarmboy21]

http://s636.photobucket.com/albums/uu88/thefarmboy21/?action=view&current=photo.jpg

This is the mystery wire. Each side has fuseable links and it seems to have been routes towards the GP controller. It has constant voltage of 12 volts.

 

[Thefarmboy21]

Also, any ideas why when I switch the fuel tank selector the gauge doesn't move, or seem to be working?

 

[OLDBULL8]

Also, any ideas why when I switch the fuel tank selector the gauge doesn't move, or seem to be working?

This may help you troubleshoot it. Could be the contacts inside the FSV.