Ok here's the theory (on the bad batteries, not the backfire). When I went to cross terminals on the bad GPR (when I tried it the 2nd time) I got an intense spark..like a welding torch. Told my brother about it and his thought is that the GPR was shorted out, and when I did that I was grounding it out.

If this is the case, that negative charge could easily destroy a battery. No? The batteries are indeed DEAD, and the GPR has fixed my starting issue. Today we jumped the truck and she started beautifully...starts beautifully as long as a 24V Cummins is attached.

ALSO..if I didn't have enough cold cranking amps, would it turn over fast enough to get the oil pressure up?

Replacing the batteries on warranty tomorrow morning so, we'll find out in due time if I have any remaining issues.

I gotta get me one of those fancy volt meters..

Stewart. I don't have to, you guys do it to yourselves.


And YES, I can cook. Dinner was potato cheese soup, and it was damn good.

 

I would think a small spark would be normal but a welding arc would indicate a direct short to ground somewhere, most likely the GPR like you figured. Easy way to check would be to remove the leads from the large terminals on the glow plug and touch them together. If you get a much smaller spark by just touching the wires together, then your GPR is(was) toast. If you still get the same intense spark, then you have something going on in your wiring harness (most likely under the valve covers). If so, find the grounded wire and correct the issue.

Of course be careful when disconnecting the wires from the large terminals because the battery side is hot all the time so you should slide some sort of isolator over it to ensure it doesn't touch ground while you are trouble shooting the issue. I have a spark plug boot that I use for stuff like this but with those large rings on the ends of the wires it might be difficult to use. If so, I would find a plastic spray can lid and cut two slits down the sides at 180 degrees apart. You then can place the hot wire in the cap and use one of the slits to hold it in place while you are testing things out. In theory, if your GPR was bad then you would have manually lit the glow plugs by touching the wires together, started your truck and then walked back out and pulled the wires apart.

Definitely could yes.

Good question. Not sure on that one.

That's cool that you have a warranty still. I hope the new relay fixed your issue and you are rolling along without any more issues. However, I still think it's possible that your short is somewhere else and if so, that could have been what took your relay out in the first place. It would be nice piece of mind to be sure.

Now that you have a known good relay, you can pull off the large terminal wire from the glow plug side of the relay and manually touch it to the other large terminal (battery side). If you get a small or no spark...then I say you are good to go when new batteries are installed. If you still get a whopping spark, then you are going to fry your relay and then your batteries all over again.

Volt meter
Amazon.com: Vector VEC008 Digital LCD Voltmeter, 12 Volt: Automotive
Prices range from $6.99 plus shipping to $11.99 with free shipping. I bought 2 at the lower price and paid the single shipping charge. My wife likes having it in the cab of her PSD as well.

We had chicken and rice soup and it was damn good as well.

 

Funny you mention this. Actually last night, I disconnected the HOT side from the GPR and touched it to the other post to get the glow plugs to charge. I got a small blue arc until I touched metal to metal..but no "positive" sparks like I did when I was trying to cross posts with a screwdriver. I didn't touch the wires together, however.

I did that with naked hands. Guess I should be more careful in the future. Wouldn't be the first time I zapped the begezus outta myself.

Wondering...if one of my battery connections (the ground) wasn't properly secured, would I have similar grounding issues or are we still looking at a possible wiring harness issue?

 

I've never jumped one with a screwdriver, but I would expect a huge spark. Aren't you really grounding eight glow plugs? They just ground out with a resister of some sort in them right?

 

Oh and you shouldn't be able to make yourself ride the lightning unless you touch some of the injector wires somehow. That's a higher voltage. The 12v has good amperage to make you jump but it won't zap you. Unless you touch your tongue!

 

Not supposed to. I've done it a few times without that reaction. You're only completing a circuit that the GPR performs every time you flick on your key.

 

12v won't hurt a thing. I doubt you would even feel it.
.
ANYTHING that is electronically controlled won't function properly unless it has a good clean source of power.
A poor ground connection will disrupt the flow.
I clean ground connections all the time at work to resolve drivability concerns.

 

Its not the volts that hurt, its the amps! get your wedding ring or watch between the positive post and a ground! then watch the blisters form! had a friend helping a friend install a winch. he was connecting the bat cable to the motor when his friend connected the other end to the bat! grounded his ring COOKED his finger, to the bone! took several skin grafts to heal up.
be careful out there

Barney

 

Put the batteries on a trickle charger last night. Cleaned terminals/ends and resecured and truck started over great this morning.

Walked to work today and left the truck on the charger..looks like they were holding a charge but still weren't completely done. We'll see if these batteries can be saved

 

This write up has saved a deeply discharged battery that I thought could never be brought back to life. Id paste it here but im on my phone.
Optima Product Support : Tech Tips

 

Thanks for the link. I read this in a magazine a while back and tried it on my watercraft batteries and it worked great. I used Option 2. Those AGM batteries are expensive...

 

Small blue arc is normal...especially at night when its easier to see. Sounds promising that your GPR was in fact bad and you solved your issue when you replaced it.

Like Dan said, there really isn't much danger handling wires with only 12v. What I meant was to be careful with that loose wire because it has the ring terminal on it and could easily touch some metal part of the engine and start sparking. There is a fusible link in that wire and if you accidentally let it touch ground then you could burn up that link and then you'll have to replace that section of the wire. In fact, I am surprised that link did not fail if your GPR was shorting out that bad. It's there to protect your batteries and the rest of your electrical system.

I also agree that it's best to remove any rings or watches while working around the batteries or electrical system in general. One of my neighbors was seriously injured when the wrench he was holding touched the positive and negative terminals at the same time and his gold ring burned his finger pretty bad.

Bad grounds cause all kinds of problems. It's the most important connection in my opinion. I had a loose negative cable and discovered it by accident so it's easy to over look....that's sorta why I went ahead and picked up a couple of those volt meters just to see if anything freaky was going on with my system.

Good luck with the battery charging. Hope they can be saved.

 

Thanks for this Keith. Looks like what I did was the right thing. Battery was taking charge so I left it on the trickle charger for a night and a day.

We'll find out here real quick if I managed to save them. Last night my brother came over and we put all new ends on my cables..found a really funky connection and some swelling on some of the cables. The main ground was in horrible shape. In fact, when we cut the end off, we found corrosion way up into the wire. I'm going to get a new set made, they're just in too bad of shape. Right now it seems we've resolved the problem. This morning I'll find out if the batteries are maintaining a charge.

 

that voltmeter is sweet! i want one!

 

Lisa if you have the coin to do this, Interstate battery has OE quality positive cables for our trucks for $71.58.

Ed, why does your website only list cables for gas engine trucks?



Quick~Cable: Ford Diesel Battery Cable ~ All Battery Sales and Service