There are reports of the pigtails or internal harnesses being miswired. One guy had his gasket short out to ground, but only when he torqued down the cover bolts.

 

I hadn't heard that yet, however when i changed mine i was in a hurry and picked up the dorman gaskets, i haven't had a problem with them yet, tightened them to spec and they've been working fine for 5000 miles so far. i did have a little problem getting the pin to line up on one of the connectors however i think thats because i didn't change out the connectors on the engine harness, there was no damage to the harness so i didn't see a need to it took a little wiggling of the pins in that connector but i got it and its been working great. but to each their own everyone likes doing things differently thats the best thing about these sites is everyone can compile information and use what they want

Dorman® OE Solutions™ 615-202 - Diesel Valve Cover Gasket | O'Reilly Auto Parts

 

Finally getting a chance to get back to work on it. Ive got to get this thing fixed, my wife is getting stingy with her truck. And, I pay for it! LOL. Got one valve cover off, now for the hard one.

 

Ok, I have the valve covers off. One of the gaskets has a pin in it that is burned. You can see where the plastic is melted around where the pin goes through the gasket. The outside connector is burned on the corresponding pin. Other gasket looks to be fine. I ohm'd them inside to outside, .3 ohms. not much resistance, I guess? It had autolite 111 gp's in it all of them are showing infinity, wide open. Except one, it shows 1.1 ohms, I assume it is trash as well. My local oreillys has the motorcraft zd11 in stock and dorman gaskets. I am going to change the gps and the one gasket of course. My question is, why would it burn all the glow plugs up that fast? Are autolite's junk? Or is there something else wrong? Could my relay have dirty contacts? Causing excess resistance, and frying my plugs? Should I just bite the bullet and change both gaskets, all gp's and the relay? That's expensive, but if that is the route I need to take to avoid future problems, I will. Please give me your advice on this since I now have them out. I really appreciate all the help. Heck if it costs me $300 bucks, it beats the heck out of $4000.00. I know it is a good truck, so its probably worth the effort.

 

All glow plugs and the bad gasket for starters, plus wiring on either side of the bad gasket if it's damaged. Other side is your call. Inspect more closely, including all associated connectors. Autolite GPs are BIG no-no; they can swell and become impossible to remove. Cross your fingers before you start removing them.

So what relay (what brand, how old) is in it now? New relay would probably be in order, as the existing one has probably been overworked.

 

Allready have all the gp's out. Tested them on the bench. The relay is original equipment. Sounds like I should do the whole system to be safe.

 

Installed the new pigtails today. I twisted the wires together, and soldered and heat shrinked them. I figured this would be the best way to reconnect them. If not someone please tell me. It looks like the 3 inner wires are the signal wires to the injectors. They were protected by a foil shield and a drain wire wrapped around them. apparently to protect them from induced voltage from the high current on the Glow plug wires. I still have to rewrap them and install the loom. I am planning on doing that in the morning, then firing it up, and seeing what happens. Wish me luck. Any more pointers, would be appreciated. thanks for all the info so far. Keep those fingers crossed.

 

It runs! I guess I did something right! I just hope it holds up!

 

Awesome! And your assessment is correct; those foil wraps tie to a wire that goes to the IDM ground. Solder and heat-shrink is the best way to splice, for sure.

 

I'm thinking my problems are fuel related, but I have no idea, I might have wired one of the pigtails wrong, the colors don't match up like old wiring.. dorman by the way, it's the new style UVCH which is a solid piece instead of the internal connectors being able to disconnect from the harness.

anyone who cut and spliced have of a picture of the colors of the new harness and the old wiring match up? I would greatly appreciate it!!

 

Last winter I had a IDM print out supplied by Darin in this thread. It helped me a lot. I did the SD mod on my uvch and the colors didn't match up. Sorry, its a long thread but there is some good info in there that your looking for.

https://www.ford-trucks.com/forums/1...-mod-list.html

 

I'll have to read through this. If you don't mind me asking, in short, what was the SD mod for the UVCH? I know I wired it right, because the truck started and ran for about 15 miles. And then just died about exit 300 coming from Ogden to JC. But she smoked like the dickens, probably from a gunked up injector that hadn't fired in a while(bare wiring/short).

It's funny, when my truck was running, nobody wanted to buy it. When it doesn't run, well, the other day, I had somebody offer me 1100 cash in hand for it. I declined it. I've put too much blood and time in the truck for it to be worth selling. I imagine all they wanted was the frame anyway.

 

haha, its a long thread! The SD mod in those years only used one plug per side and supposedly had thicker wires to help stop the plugs from burning up. It sounds like you have another problem unless one of your splices came apart.

Yeah, when your down, someone always wants to take advantage of you.

 

Well, I'll check the pigtail wiring. I used butt connectors, I might go back and get a soldering stick and solder the connections, and then wrap with elec tape. Stabalize the connections.

I found an upper wiring harness for 125$ a good deal? I'm about to jump on it, it looks pretty clean for an Ebay buy, and it's a private seller, the harness looks clean, it just has the battery connections cut, but I don't need those, or the starter wires.. I just want a harness that's clean and verified to run. I have a lot going on with the fuel system, but I'm about to go turbo on this truck to the tucker max.

 

Yeah, I think its best to solder the connections and then use het shrink. Then wrap it with that foil in there. The harness sounds good and they are hard to find.