I just bought an '86 f-250 with a 6.9l diesel. So far I like it. The glowplugs aren't currently working though. I haven't had time to really look at them yet but am planning to this weekend and was wondering if anyone knows where to find a detailed wiring diagram. I bought a chilton manual but it is a bit vague on specifics
any help would be appreciated

 

congrats thats what i started with and now i have 3 of them.. wonderful engines.. good gas millage and good power for offroading.. last long time also.. cheap to maintain too!! cant be beat.. unless your hauling a 20000 lbs trailer up moutains.. then maybe... but i dont use mine to tow much.

Ray

 

Blacktomato,
Welcome to FTE and the IDI diesel forum.

What do you want to know about the wiring?

 

thanks for the welcome. I'm looking forward to getting to know my truck.
I guess I have to take a close look at the setup and do a bit of testing before I can tell you exactly what I need to know Dave
I was just wondering if there is a wiring diagram out there that would cut down the time that I have to spend assessing how the system is set up

 

The 86 and earlier glow plug system is rather complicated.
In the Haynes Diesel Engine Repair Manual #10330 there is a diagnostic process.
About 3 pages of it.

I will start by saying as long as the system is working, there is no finer system on the market.
Next line goes like this, the system is tied into so many things, that once it fails there is no bigger headache than trying to figure out what is wrong.

I went through all the diagnostics, several times.
Glow plugs were failing way to soon.
Then one day as I was driving down the road, I see the glow plug light is ON.
The engine was at operating temp, the light should not be on.

So I figure it is the controller.
I go to price one, well over 200 at the time.
And to many stories about the controller breaking off when you try to remove it.
Rear of the head, in a hole into the coolant passages.
If it breaks off, you have to pull the head to get it out and stop the coolant leak.
I soaked mine with PB Blaster for a couple days, tried a wrench on it and it did not budge.
After the stories about it breaking I did not pull on the wrench very hard though.

I then converted mine to manual glow plugs, and that has been a very long time ago.

If manual glow plugs sounds OK to you, it is easy to do.
Which way would you like to go?

 

thanks dave - sorry I haven't got back to you I have been very busy wiring my folks house
anyway, I looked at my truck for a minute today and noted that the purple wire on my relay (behind the battery) is cut. I believe this is the controller wire. given what I've read about controllers, I think I'll just go manual switch.
any tips on this?

greg

 

Find a fuse that only has power when the key is ON.
Run a wire from there to a momentary switch.
Off the other terminal of the momentary switch run a wire out to the purple wire terminal.

Done wiring.

To operate, turn the key to on, push the momentary switch 10 seconds, start the engine.

The wire can be a small AWG wire, you are only tripping a relay.
Getting power from a fuse that is not hot when the key is off is a good safety measure if children ever get in and start flipping switches and pushing buttons.

 

thanks dave. I will try this

 

these diesels gt simple wiring for sure! should be easy 4 you.

Ray