Big K
SDD.com Hacker/Admin
UPDATE:
He's got it running ,,,,Turned out to be a bad spot in the harness
He's got it running ,,,,Turned out to be a bad spot in the harness
BlueMule broken down in Albuquerque, New Mexico
- Thread starter hheynow
- Start date
rickh
Biodiesel Rules!
For future reference...
When the idm detects a short it will drop the entire back to protect itself.
Glad his adventure ended ok.
Better than being stuck in the cold snowy noth, unless he was in the mountains.
Rick H...
When the idm detects a short it will drop the entire back to protect itself.
Glad his adventure ended ok.
Better than being stuck in the cold snowy noth, unless he was in the mountains.
Rick H...
Big K
SDD.com Hacker/Admin
Yeap, It will
94f450sd
certified nutjob
yes.the 7.3 is known for burning the wireing under the valve covers and the gaskets.sometimes it gets the main harness as well.and as was said when the IDM detects a problem it will normally shut down the whole side of the engine with the short to protect itself.sometimes this doesnt happen fast enough or the owner keeps trying to start or drive it and burns out the IDM.a new IDM is $987.13
.i keep a spare gasket,2 UVC harnesses, and 2 main harness plugs as well as an IDM in my truck at all times with the tools to swap them if needed.
arrowstrap
BioMechanic
There has got to be a final solution to the UVC harness issue! if the wire gauge is too small to handle the current why not just beef up the wire gauge and save everyone the headache?
I've had to replace mine twice.
I've had to replace mine twice.
action4478
Full Access Member
This from Racer_X ....:
Excess resistance in the circuit is what causes it to burn the harness. Wiring is to small to handle the heat when the plug doesn't use the amps up to heat the tip. Heres a simple explanation:
Ford/Nav VC gasket/harness was redesigned with better conductors several years ago. Here's a basic way to explain it without math at all:
If the glow plug (load) were to short, the burn or weld will happen at the point the short occurs. If you use a welder it welds at the electrode (load). It won't burn up your weld cables.
So why does the harness connector melt? Excessive Resistance causes heat. A GP has little resistance or ohms. It's nearly full power that warms the tip using up power to make heat. What little power isn't used returns thru ground to battery completing the circuit. Excess resistance or poor conduction from green stuff or corrosion prevents full power from flowing to the load (glow plug). The wiring gets hot and melts because you still have a complete circuit back to battery ground, but no load to use the power up and keep the wiring cool as power flows thru it.
Now think of the welder again. What happens if you forget to put a ground clamp on the metal to be welded and touch the electrode (load) to the metal? Nothing. The circuit is not complete, so no power flows at all. No weld or short.
Best way to prevent the burned wiring is a good conductor to your GP's. I pack Di grease in all underhood connectors. The best way to keep the connection moisture free and clean is silicone dielectric.
If your harness burn't from the GP connector back, then you may have a shorted plug. Ohm it, compared to the others. If it ohms out higher than the rest it's also BAD. The extra resistance is inside the plug, not allowing full power to the tip.
-
Excess resistance in the circuit is what causes it to burn the harness. Wiring is to small to handle the heat when the plug doesn't use the amps up to heat the tip. Heres a simple explanation:
Ford/Nav VC gasket/harness was redesigned with better conductors several years ago. Here's a basic way to explain it without math at all:
If the glow plug (load) were to short, the burn or weld will happen at the point the short occurs. If you use a welder it welds at the electrode (load). It won't burn up your weld cables.
So why does the harness connector melt? Excessive Resistance causes heat. A GP has little resistance or ohms. It's nearly full power that warms the tip using up power to make heat. What little power isn't used returns thru ground to battery completing the circuit. Excess resistance or poor conduction from green stuff or corrosion prevents full power from flowing to the load (glow plug). The wiring gets hot and melts because you still have a complete circuit back to battery ground, but no load to use the power up and keep the wiring cool as power flows thru it.
Now think of the welder again. What happens if you forget to put a ground clamp on the metal to be welded and touch the electrode (load) to the metal? Nothing. The circuit is not complete, so no power flows at all. No weld or short.
Best way to prevent the burned wiring is a good conductor to your GP's. I pack Di grease in all underhood connectors. The best way to keep the connection moisture free and clean is silicone dielectric.
If your harness burn't from the GP connector back, then you may have a shorted plug. Ohm it, compared to the others. If it ohms out higher than the rest it's also BAD. The extra resistance is inside the plug, not allowing full power to the tip.
-
arrowstrap
BioMechanic
yeah, i read that post but it's not really a solution.
the wires should be larger gauge and there should be a fuse link to shut down the overheating plug before it destroys everything.
the wires should be larger gauge and there should be a fuse link to shut down the overheating plug before it destroys everything.
