HAHAHA thanks a lot

 

Depends on what you're measuring. If you're checking resistance of the glow plugs, set it on the lowest ohms setting, since they're pretty low resistance (aprx. 1 ohm). If you're measuring voltage, since you're looking for 12-ish volts, the typical range to select is 20VDC.

 

Thanks a lot Magpogue, I'll get to it again and hopefully this time I get a reading. By the way, cool user name

 

Ok I went out and checked again with the multimeter in the right position. I checked the batteries first to make sure it worked. It does. Put it in DCV 20 and pulled back the little boot to get clear access to the hot side of the relay. I couldn't get a reading or to be more clear it read 0.00. I tried to ground it on different parts of the motor, alternator, negative side of the battery, but it still read 0. Do you guys think it's in the wiring? I don't want to take it to a mechanic unless I absolutely have to. I want to learn as much as I can and fix it myself. You all know how it is. You guys have been great and I'll fix this truck if that's the last thing I do hahaha. If it was easy everybody would br doing it right? Thanks again for all the help. -Z

 

If your meter is an analog one (with a needle) you'll have to observe the polarity for it to work. Black lead to ground, red lead to the positive wiring. If you don't have power on either wire on the GPR you need to trace the wire back and see why you're not getting power. I think that wire should be tied in at the starter relay. I wonder if someone replaced the relay at some point and may have put the wire to the GPR on the wrong side of the relay. If that's the case you wouldn't have power to the GPR unless you were cranking the starter.

Where are you from Z? I just noticed that you're from Ohio. If you're close enough to me, I'd love to help you out.

 

^^^^^ Correct about the source of power to the hot side of the GPR. Take a look at the starter relay. One "big" terminal has a bunch of wires on ring terminals attached to it; the other has only one wire. The single wire is the one going to the starter solenoid. The other terminal with all the wires is acting as junction point. One of those ring terminals is the "main" feed from the battery. The rest go to fusible links that energize the underhood fuse box, the headlights, etc. So it's just a convenient distribution point; it doesn't depend on the function of the starter relay itself.

One of the wires (or technically, a parallel pair of fusible links) coming off that junction goes to the hot side of the glow plug relay. So do the same voltmeter check on that terminal of the starter relay. You should get voltage there; if you didn't have voltage there, nothing in the truck would work. So presuming you get 12-ish V there, that suggests the connection from there to the GPR hot side is bad. As said, that's actually two fusible links in parallel; they look just like regular wires on the outside, but they're rigged to burn up internally and open the circuit when overloaded. They may have just burned up from years of use. If you really want to get fancy, you can disconnect that link pair at both ends (from the starter relay and from the GPR), and set your meter on continuity check, if it has that capability, and put the probes on each ring terminal and see if it shows continuity.

 

I live in Logan Ohio in the Hocking hills area. My meter is not analog but digital so I'm going to go ahead and start checking the starter relay. You may be right about the wrong side of the relay. Thanks a lot

 

Thanks a lot. Can I get replacement wires from Napa, or do I have to order them?

 

Ok, I found the wires but this is what I'm gonna do. My head is spinning a little with ideas and problems and alike, so I'm going to burn some brush in my field and look at it again with a clearer head in a couple of hours. I'll post an update as soon as I have one. -Z

 

I checked and double checked. I get a 0 reading on the starter relay on the side that goes to the GPR. The other terminal I get a little over 12 V. So can I just take it off the one terminal and put it on the other?

 

If we're talking about the starter relay on the fender, and the wires that go to the GPR are on a terminal that doesn't have power when the other side does, it is on the wrong terminal. That terminal is only energized when the key is turned to "start" and the relay is pulled in (cranking the truck). The wires for the GPR should be on the side of the relay that all the other smaller wires are on. The only wire on that side should be the one that leads down to the starter. Here's a pic.


And another:

One more (this one I actually took myself):

 

Thanks Nate, yeah it was on the wrong terminal and I changed it. Now I have 12-ish V on the relay and when I had somebody turning the key, I had just under 10 V on the side that goes to the GPs. If it doesn't start now, the rest of the problem would be the GPs and the wiring harness. Is that right? BTW the GP relay was clicking a little bit after I got done and the key got turned. that's normal right?

 

I guess I wasn't that clear; the "not hot" side of the starter relay ONLY affects the starter. If you have 12V on the "hot" side of the starter relay, ONE of those ring terminals stacked on that stud is for the parallel pair of fuse links that goes to the GPR. So since you have voltage at that stud, it's probably that pair of fuse links that's blown. Or, sometime over the years, someone replaced it with a straight wire, and that wire is damaged or shorted. So start by disconnecting both battery negatives. That keeps that "hot" stud from being energized, so you can work with it without your wrench becoming an impromptu arc-welder. Then take the nut off that stud, and start pulling ring terminals off, until you identify the one that goes to the GPR. THAT is what you'll need to diagnose/fix.

Do NOT move the wire from the other big terminal on the starter relay over to the "hot" stud. That goes to the starter solenoid, and as soon as you touch that ring terminal to the hot stud, the starter will start cranking. Another good reason to disconnect the battery negatives. Esp. if it's a manual transmission truck, you do NOT want to run yourself over by cranking the starter.

 

Thanks I'll try that next. I only wish my truck was a manual so that wont be a problem. I found the the wires going from the starter relay to the GP relay it was on the "not hot" terminal.

 

If you moved that wire you should be okay now. Try it and see if it starts.