6.9 starting probs...
Thread Starter
|
Postmaster
Joined: Feb 2003
Posts: 3,441
Likes: 5
From: Muskegon, MI (home)
6.9 starting probs...
Hey guys I am new to the diesel scene but geeked to learn more. I have a basic understanding of the function of the fuel injection system of these engines. I have been experiencing some starting problems with my 84 F250 with the 6.9. When I turn the key on the glow plug light comes on then comes off after a few seconds and the engine starts fine and runs fine. When I shut the truck off and let it cool down for a couple hours, I go in and try to start the truck... the glow plug light does not come and the truck won't start unless I turn the key into the on position and jump the posts on the glow relay. What seems to be the problem here? Any help is appreciated!
Tuned
Joined: Oct 2004
Posts: 250
Likes: 6
From: new york
Sounds like your glow plug controller is on the way out. On your truck 84 it is threaded into the coolant passage. If you take off the air cleaner and look toward the back of the engine you will see it, its about 4" behind the air intake a little toward the driver side, it stands about 2" and has a harness with several wires plugged into it.
Be careful when you take it out, I have had the break off which makes it a real pain
The other thing you can do is install a push button switch, basically save opening the hood, just pick up battery voltage from the fuse block and run a wire to the glow plug relay. Just hold it down 10-20 seconds untill it fires. I wouldn't go any longer than 60 seconds with old glow plugs, there is no telling how much they will take! hope this helps
Be careful when you take it out, I have had the break off which makes it a real pain
The other thing you can do is install a push button switch, basically save opening the hood, just pick up battery voltage from the fuse block and run a wire to the glow plug relay. Just hold it down 10-20 seconds untill it fires. I wouldn't go any longer than 60 seconds with old glow plugs, there is no telling how much they will take! hope this helps
Elder User
Joined: Sep 2007
Posts: 518
Likes: 0
From: Huntsville, TX
I have a push button gp switch, and have heard mixed reviews about it. I was told it makes your gps go out quicker, but as long as you don't use autolite gps and you dont hold it longer than about 10-15 secs you should be okay. I only hold mine down for 7 secs religiously.
Post Fiend
Joined: Nov 2003
Posts: 21,285
Likes: 15
From: Nutter Fort, WV
The old style glow plug system uses coolant temp to figure out if you should need glow plugs or not.
The coolant temperature sensor is what seems to fail first in the controller.
When mine failed, it went the other way and turned the glow plugs on while driving with the coolant up to operating temp.
Short glow plug life was the result.
In the picture the yellow wire goes to my dash installed momentary switch, the purple wire was from the stock controller which is no longer installed.
I picked up power for the momentary contact switch from a fuse that is only hot when the key is ON.
Turn the key to ON, push the button for 10 seconds, start the engine.
The coolant temperature sensor is what seems to fail first in the controller.
When mine failed, it went the other way and turned the glow plugs on while driving with the coolant up to operating temp.
Short glow plug life was the result.
In the picture the yellow wire goes to my dash installed momentary switch, the purple wire was from the stock controller which is no longer installed.
I picked up power for the momentary contact switch from a fuse that is only hot when the key is ON.
Turn the key to ON, push the button for 10 seconds, start the engine.
