Throttle cable melting

Evansline

Registered User
Joined
Apr 20, 2022
Posts
12
Reaction score
1
Location
Shell Knob, MO
Recently got a 1989 7.3 idi with the 093 turbo. The previous owner had recently replaced glow plugs and glow plug controller. Have since burned up 2 throttle cables in a matter of no time. Here is what I’m thinking and would appreciate any advice:

1989 didnt have a factory turbo. Need to wrap the throttle cable with some heat shield. The 89 cable is longer than the 93 turbo cable, so thinks that is the route m.

Need to eliminate the source of the heat. Suspect the glow plug system is more of the problem than the turbo. The glow plug controller is new but I don’t know what brand or if the harness is bad etc. thinking I just rip it all out and do CDD’s kit.
 

Clb

Another old truck
Supporting Member
Joined
Mar 1, 2013
Posts
4,988
Reaction score
1,439
Location
nannyfornia
Try and verify routing, actual heat sources causing the melt, and will the longer line get away from the heat...
 

Cubey

Full timer RVer
Joined
Oct 18, 2017
Posts
3,604
Reaction score
1,310
Location
USA
Glow plug controller seems to be really hot, is that normal?

The controller itself or the relay on top of it? Neither should be super hot. If the relay is hot, it may be stuck on? You sure it's not just engine heat heating it up too?
 

snicklas

6.0 and Loving It!!
Staff member
Joined
Aug 7, 2006
Posts
6,044
Reaction score
2,140
Location
Greenfield, Indiana
The Z resistor will get hot during operation. Is the plastic cover still over the relay? If not, you could be shorting across the 2 big lugs of the relay with the throttle cable, causing it to melt……..
 

Fixnstuff

Full Access Member
Joined
Sep 28, 2015
Posts
213
Reaction score
67
Location
Kitsap County, Washington
YES that 'Z' bar resistor gets EXTREMELY HOT. Hot enough to ignight any combustible material that comes in contact with it, possibly starting an engine compartment fire. That's why it has a vented plastic cover over it.
IF the controller or controller relay itself ever fails where the relay is in the stuck closed position (ALWAYS ON = GLOW PLUGS ALWAYS ON) the heat will melt through/burn through the plastic controller cover and completely drain down both of the batteries in a few minutes, (maybe 5 minutes)
You'll know when all of your gauges stop working because the alternator current will be drained to the shorted glow plug relay circuit and not enough electricity to power any gauges or lights.
That happened to me a few years ago.
 

Old Goat

Full Access Member
Joined
Jan 14, 2021
Posts
515
Reaction score
365
Location
Northern Nevada
You said you have a Turbo. Then wouldn`t the GP Relay have been moved over to the pass side Valve Cover?

Goat
 

Cubey

Full timer RVer
Joined
Oct 18, 2017
Posts
3,604
Reaction score
1,310
Location
USA
The Z resistor will get hot during operation. Is the plastic cover still over the relay? If not, you could be shorting across the 2 big lugs of the relay with the throttle cable, causing it to melt……..

My solution was to put some plastic wire loom over the throttle cable to insulate it. Works nicely on the F250.
 

Nero

Full Access Member
Joined
Jan 3, 2022
Posts
453
Reaction score
348
Location
OR
That's weird, all ATS kits I've seen move it to the passenger valve cover, and all Banks kits I've seen had a little stand that bolted onto the valve cover.
 

Cubey

Full timer RVer
Joined
Oct 18, 2017
Posts
3,604
Reaction score
1,310
Location
USA
That's weird, all ATS kits I've seen move it to the passenger valve cover, and all Banks kits I've seen had a little stand that bolted onto the valve cover.

Well, when it comes to 6.9s, they don't have to relocate it. On my E350, the GP relay is above/behind the LH headlight. And it has ATS 085.
 

Nero

Full Access Member
Joined
Jan 3, 2022
Posts
453
Reaction score
348
Location
OR
To clarify, truck chassis locations, not van bodies :joker:
 

Cubey

Full timer RVer
Joined
Oct 18, 2017
Posts
3,604
Reaction score
1,310
Location
USA
To clarify, truck chassis locations, not van bodies :joker:

6.9 trucks had the controller and relay elsewhere too, different setup.

6.9 style controller:
You must be registered for see images attach
 

Old Goat

Full Access Member
Joined
Jan 14, 2021
Posts
515
Reaction score
365
Location
Northern Nevada
6.9 trucks had the controller and relay elsewhere too, different setup.

6.9 style controller:
You must be registered for see images attach

Correct, that is where the Controller is on a 6.9.
The 6.9 truck has the GP Relay over on the passenger fender area.
Have no idea how a Van it plumbed. Actually never have come across one in the yards, so far.

The poster of this thread has a 7.3 engine, and the new style GP Relay/Controller is one unit mounted at the rear of the engine.
If a Turbo is installed, then it is moved to the Valve Cover.
At least the ones I have seen in person and pictures on the Forums.

Seems it would get a little toasty with the Turbo there if not moved, and difficult to get to.

Goat
 
Top