I have a 1985 F250 XL with a 6.9 diesel, I have had some problems with the glow plugs to the point were you must use starting fluid to start it. There was some work done to it a few years ago and they replaced the glow plugs and some other electrical components, however shortly there after the same problems came about. Now I know some of the wiring is pretty hacked together (not by me I might add) so I'm guessing that does not help. I was wondering if anyone knew of a similar problem and thier fixes, or a replacement harness, any help would be appreciated.

 

i had to make a couple harnesses for people, you can do it a whole lot cheaper than buying one. Take yours off and make it one by one so it fits neatly. get wire that will handle the load, dont short cut this step because you are in for a tring afternoons work. It would suck for it not to perform right for a long time. I used heat shrink on all connections to help prevent oil from aiding in wire breaking down. Hope I helped

 

Make sure you have good glow plugs too, motorcraft/Beru are the best. Other brands have been known to burn out quickly and even swell making them difficult to remove. The tip of the plug usually breaks off and could result in having to remove the cylinder head to get it out.

 

Thank you, now it should be intresting to redo the wiring harness seeing that it is hacked to hell from previous owners.