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Glow plug light no coming on...

Mezmorized

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Location
Ottawa, Ontario, Canada
Looks like the glow plug wire going to #1 cylinder fried when I last tried to start my truck. Now the glow plug light isn't coming on. I've checked the fuse in the underhood fuse box, it's good... Where to check next?

Why did the wire fry? Did the glow plug short out? If I disconnect that glow plug wire, will the other glow plugs and controller work?
 
The wire is made of fuseable link wire. If you repair the wire instead of replacing that banks harness you can't just crimp connector on a piece of regular wire.

Disconnect that wire from the glow plug and carefully inspect it and all the other wires on that bank for a short to ground.
The quick diagnostic is to disconnect that bank of wires from the controller, then turn on key for WTS light to see if there is other damage in the system.

I would remove that glow plug and bench test it to make sure it heats up properly and didn't short to the housing. Remember the antisieze when reinstalling.

I've never heard of fuseable links just frying due to age, I have always found a problem when that happens.
Let us know how it's going...
 
Welcome to antique diesels. I have seen links fail and fry due to age and rust.
You do need to check for shorts and simply replace that glow plug just to be safe. Heats up and shorts is possible but reads fine cold.

Age of the plugs will help decide if you do all 8. How many miles on injectors and how hard do you run the engine? Any starting aid use?

No glow plug light means no power on the glow plug harness side of the relay. The relay is not working, coroded terminals at relay, blown fusiable links. There are several fusiable links. One to the relay so check for 12v at the terminals. Then from the relay each bank gets a link then each plug. If the bank link also fried it controls the light. I forget what bank powers the light. The relay contacts could also be bad. Voltage during glow cycle will tell the story.
 
Heres a copy of teh glow plug wiring diagram. There is a fusible link going to each bank of cylinders, and then another fusible link to each individual glow plug according to this. The glow plug light gets it's power from the drivers side bank of cylinders, so it sounds like you popped a fusible link furthur up along with the one for the #1 plug.95 glow plug circuit.jpg
 
"Welcome to antique diesels. I have seen links fail and fry due to age and rust. "

That makes sense, I haven't experienced it but here you go teaching me again.

Driver side bank for signal? My whole rig is bass ackwards from you guys'. Sorry bout that.
 
The truck is used in the summer for towing the 24' enclosed trailer. I bought the truck about 3 years ago with the glow plugs that are in it. The truck has just over 300,000 kilometers on it. Been having a hard time starting due to a possible leak I can't find yet between the tank and the LP. When I last cranked it over, there was a bit of smoke from under the hood while cranking, I'm thinking that was the wire to the #1 GP that fried cuz it smelled a bit like electrical... just a bit.
 
Ok, no voltage draw when turning on the key so the GP's are not going through their cycle. Checked the GP fuse and the Eng 1 fuse, both are good. Current is reaching the battery side of the GP Controller, I did hear a click when I cycled the key to see if the GP light would come on. I'll have to get someone to help me see if there is power on the GP side of the controller when I cycle the key. It looks like the #1 GP connector was so close to the exhaust manifold that it finally wore through and shorted out taking the fuse link with it.
 
Put a volt meter on the windshield and run the wires with clip attachments to the controller and ground. Look at the meter or light when you cycle the key.

This way when you only have 3 people to help you you can see what is going on. Most of the time I have three people working on my truck - Me, myself and I. :hihi:

Usually the $50 transistor in series with the 15 cent fuse will blow first to protect the 15 cent fuse...
 
Here is my truck, got it started by running booster cables from the battery to the GP side of the controller. And yup... it's stuck in the ice. I'm going to have to wait until it gets milder out to move it. Then it will probably get stuck in the mud!!

[video=youtube;dDKywVfR4Nk]http://www.youtube.com/watch?v=dDKywVfR4Nk&feature=youtu.be[/video]

(I'm still uploading the video)
 
IDK color of wire, but for a hard to find leak (sucking air) I will drain the fuel tank then hook up a evap smoke tester flooding the tank and lines with smoke to find the leak. If you do it with fuel in the tank it will not go into the supply line. This will not test infront of LP. You can try disconnecting line from the input side of LP blowing air back into the tank, but I haven't had good results that way.
If you don't have an evap tester google a DIY one using a glow plug and babyoil (food grade mineral oil).

I've seen that white stuff on the ground before here in Vegas once, but can't remember what it's called...
 
From the looks of how much fuel/air was coming out I'd suspect bad or intermittent LP/OPS. also could be plugged tank sock
 
The LP is a new unit so maybe I'll swap the OPS.

However, the other day I was running it with power to the diagnostic connector to run the LP and it still started stumbling.
 
Ok, I had a thought... a couple of years ago I picked up an auxiliary fuel tank that mounts in the bed of the truck. I haven't installed it yet. But now I'm thinking of putting it in, plumbing it to a water separator, then to the lift pump and have the return go back to it. In other words, by-pass the factory fuel tank. And if that solves my problem, then I could drop the tank a little later on and fix it then. (Trying to get the truck in shape to tow the enclosed trailer with no trouble.)

What do you all think?

P.S. It's a 60 gallon tank! :)
 
First the relay mod like ak said.
If you run the other tank and the problem is gone, you know where to look in the future, but if not, you could just be adding other variables to troubleshoot. If you have an air leak in the system, that still going to be there unless you replace the entire fuel line With a new one to the new tank.
 
That relay mod will cycle the OPS without the need of oil pressure right?

I'm about 98% sure I'm taking air between the tank and the LP so that's why the auxiliary tank sounds good about now. Specially since my driveway is a mud bog right about now too!! LOL
 
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