Strange glow plug/accelerator issue

[87F-250HD]

I noticed a little smoke and an acrid smell coming from my ‘87 6.9 while it was idling, and then saw that the wait to start light was on even though the engine was running. I turned the truck off, and turned it on a little later; the wait to start light stayed on, and then when I tried to push the accelerator, it fell to the floor; seemed to have lost its connection to the throttle. I lifted the hood, and the end of the throttle linkage glowed red when I revved it. The part that glowed is the red piece in the middle of the attached picture. Any ideas about what could be going on here?

You must be registered for see images attach

 

[Kdo58]

Disconnect the high idle plug see if it happens again, or follow the throttle cable to see if a wire is rubbing it.

 

[IDIBRONCO]

It probably shorted against one or both of the power wires that go to the glow plug controller. That's why It was glowing red. That's why it burned in tow. It's also why the Wait To Start light was on. My first guess is that the plastic cover isn't on the controller which would let the throttle cable rest against those wires or terminals. It's also possible, maybe likely, that if the controller was actually activated, your glow plugs are burned out from being on for so long.

 

[DirtyWood]

When you replace the throttle cable you could use a small section of 1/4 ID fuel line to protect the jacket from chafing. I have many small pieces of heater hose, fuel hose, and even irrigation tubing protecting components from possible chafing/rubbing. Cut tubing lengthwise and zip-tie in place.

I also don't have the plastic cover for the GP relay and have actually had a piece of Gorilla tape over it that has lasted for several years now.

 

[IDIBOBS]

Move the glow plug controller iff the back wall to the passenger fender. Inspect all the wires and repair as necessary.

 

[ttman4]

When you replace the throttle cable you could use a small section of 1/4 ID fuel line to protect the jacket from chafing. I have many small pieces of heater hose, fuel hose, and even irrigation tubing protecting components from possible chafing/rubbing. Cut tubing lengthwise and zip-tie in place.

I also don't have the plastic cover for the GP relay and have actually had a piece of Gorilla tape over it that has lasted for several years now.

Tube, small hose, large hose, rubber, plastic, even piece of siphoning hose, innertube, pieces of rubber tire, many things under hood & under truck out of sight!!! All placed, stuck, stuffed here & there to keep cables, wires, any & everything from shorting out or chaffing.
That's way my "BESSIE" is & she probably an extra 500-800# more!

And as @DirtyWood said slice some lengthwise & slip it over & then ziptie along heated part or chaffed section of throttle cable.

 

[IDIBOBS]

Tube, small hose, large hose, rubber, plastic, even piece of siphoning hose, innertube, pieces of rubber tire, many things under hood & under truck out of sight!!! All placed, stuck, stuffed here & there to keep cables, wires, any & everything from shorting out or chaffing.
That's way my "BESSIE" is & she probably an extra 500-800# more!

And as @DirtyWood said slice some lengthwise & slip it over & then ziptie along heated part or chaffed section of throttle cable.

Or… and I’m just spitballing here…… one could just fix it right in the first place. Usually cheaper, easier, and longer lasting.

 

[DirtyWood]

Even the factory used chafing gear here and there. The return line from from the heater core to water pump has chafing gear where the alt bracket is close. The NOS throttle cable I installed yesterday has 3/4 of the cable covered in an extra thick layer of rubber unlike all the new aftermarket throttle cables I've seen. Just sayin' that sometimes using a piece of chafing gear is part of the right way to fix it.

 

[ttman4]

Even the factory used chafing gear here and there. The return line from from the heater core to water pump has chafing gear where the alt bracket is close. The NOS throttle cable I installed yesterday has 3/4 of the cable covered in an extra thick layer of rubber unlike all the new aftermarket throttle cables I've seen. Just sayin' that sometimes using a piece of chafing gear is part of the right way to fix it.

Where you find a throttle cable that has that extra coating?
My original cable from that '94 Factory Turbo engine I put in my '90 had the coated section. Since then I've replaced it 2 times & those 2 came with no coating.
I added my own coating, but I'm glad it's under hood & out of sight cause my added stuff looks sorta cruddy......Not worth filing for a patent!!!

 

[DirtyWood]

Where you find a throttle cable that has that extra coating?
My original cable from that '94 Factory Turbo engine I put in my '90 had the coated section. Since then I've replaced it 2 times & those 2 came with no coating.
I added my own coating, but I'm glad it's under hood & out of sight cause my added stuff looks sorta cruddy......Not worth filing for a patent!!!

NOS on Ebay. Some guy in South Dakota had it in the original FoMoCo packaging, $40 shipped, which is less than some of the new ones. If I had to make my own coating I would just use 1/4 or 7mm ID fuel hose. I checked the OD of my throttle cable and it was awful close to 1/4

 

[IDIBRONCO]

If I had to make my own coating I would just use 1/4 or 7mm ID fuel hose. I checked the OD of my throttle cable and it was awful close to 1/4

I was thinking the same thing.