HMMWV Grounding Kit Install

[GMVguy]

I purchased the Grounding Kit from Kascar (PN 535-A1) and installed it over the weekend. I know it's cheap & easy to make one yourself, but I don't have much wiring experience and for $70 I figured I'd get it right the first time. It was a quick & easy install. Here's a write-up in case it helps anyone out!

 

[TwoStates]

Awesome. Thank you and please don't remove the pics.

 

[Warthog]

Awesome. Thank you and please don't remove the pics.

That is why we ask people to upload their pictures to our server. That way the pictures are always available. Nothing no frustrating that finding a solution to your problem and the pictures are long gone.

Made this thread a sticky.

 

[GMVguy]

Thanks. This was the most inexpensive, yet effective, fix I've done. Thanks to those who've gone before me to recommend it (retiredwarhorses, etc.). It'll probably save a few PCB's over the years.

 

[Bulldogger]

Thank-you for posting the picture with the wire lengths and connection sizes. I am very DIY and plan to make my own harness. This is exactly what I was hoping to stumble across. Thank-you again Mlacek!
Bulldogger

 

[GMVguy]

Thank-you for posting the picture with the wire lengths and connection sizes. I am very DIY and plan to make my own harness. This is exactly what I was hoping to stumble across. Thank-you again Mlacek!
Bulldogger

Cool, glad it helped! Let me know if you need any more details.

 

[DeuceNewb]

I'm just starting to look into purchasing my first hmmwv, what is the purpose? Is this a recommended thing for all of them?

 

[Dock Rocker]

I'm just starting to look into purchasing my first hmmwv, what is the purpose? Is this a recommended thing for all of them?

Because of the aluminum body there isn't a way to get a good ground. From the factory the grounding network was adequate but over time corrosion and in some cases electrolysis have caused a loss of ground that is really tough on the glow plug controller as well as other parts of the charging system. This mod just helps work around a big potential problem.

Sent from my SM-N920R7 using Tapatalk

 

[WAGNUM]

Anyone know what gauge wire this kit uses? (Maybe 6ga or 4ga?) Kascar fuzzed it out on their website pic...

 

[mhb285]

Where did you get the kit from.....
Thanks

 

[Lawdog734]

While they can be made, I bought mine from Kascar.

 

[WAGNUM]

Anyone know what gauge wire this kit uses? (Maybe 6ga or 4ga?) Kascar fuzzed it out on their website pic...

Does anyone know the wire gauge on these? Be great if someone could glance at one of their ground wires and advise. Thanks!

 

[NormB]

Just wanted to post a personal thanks after doing this today.

I did a cut and paste of your photos to my iPhone to reference while I was doing the job, only the last one hung me up. Took me a while to figure out the picture is from UNDERNEATH the truck (says truck on my title). I used some Deoxit after taking a stainless steel brush and some acetone to the fittings to degrease them and wouldn't you know it, Humvee started up quicker, ran smoother than it has since I bought it. ONly took about an hour to get it done.

Now to chase down all the rest of the electrical connections and give them the same treatment...

 

[Jakob1944]

I like that....drop the money, install and move on to something else.....

 

[NormB]

Does anyone know the wire gauge on these? Be great if someone could glance at one of their ground wires and advise. Thanks!

I meant to make a note of that but didn't.

The wire seems to be of a very high-quality silicone ignition wire, about 12 gauge. Considering the environment it'll be in I opted for soldering the wire to the connectors with silver-bearing solder. No room for water to get in/corrosion to start.

I think the grounding harness might outlast the truck.

 

[CDR Ross]

Great pics. Thanks. I purchased the Kascar grounding kit and I couldn't figure out where the PCB connection was. The pics helped a lot.

 

[fordtuff06]

I was having starting issues with my M998. The glow plug wait light would flash quickly then go off. I would have to turn the switch on, then off several times and then it would start. After checking the glow plugs (which were good), I decided to make a grounding harness. I used 10 gauge wire, and ran a wire from the generator, the PCB mounting screw, the grounding bolt on the firewall, and the starter to the drivers side engine block. It fixed my starting issue. I noticed the pictures in this post, the wire looks to be 6 or 4 gauge. I am curious if my 10 gauge is to small. Like I said it fixed my problem, but I wonder if I should purchase bigger wire?

This is a video showing my grounding harness.
https://www.youtube.com/watch?v=NORo30wIdqk&feature=youtu.be

 

[CBASSETT]

Thank you for your post and pictures, I referred to this post today to assist me in the installation of my grounding cable, smart start system, thank you for this post! Great help

 

[Bulldogger]

The grounding harness many of us did, or will, install is a SUPPLEMENTAL harness to the existing factory harness for the most part. While some argue that it should be of a diameter and gauge that can handle the full discharge of two 24V deep cycle batteries, I went much smaller. I found wire that I could afford in bulk at Home Depot and put my own harness together for about $15 start to finish. I don't have the gauge handy, but it was thick enough to be hard to bend into a kink by hand, and it had to be cut with diamond jaw pliers. I made the terminations out of 1.5" lengths of copper pipe of varying diameters, whatever was wide enough to get the wire into and then flatten in the vise and drill a bolt hole through.

Half my problems went away when I installed my harness because the grounding circuit to the instrument panel was loose behind the dash. It turns out that connection has a wire bolted to the engine side of the firewall and another wire lead comes off the back of that bolt inside the cab, then connects to the panel. The bolt on the underside of my dash, on the firewall, was loose. No amount of tightening the other nuts could have helped it. My gauges don't flutter anymore!

Any grounding harness to supplement the small gauge factory one is a good addition. Clean all the connections you touch as you go and you'll improve the effectiveness of the factory harness while adding extra capacity in the form of your supplemental one.

Bulldogger

 

[Kickerson]

What diameter is the main connection on the rear cylinder head? Is that also a 3/8 hole? Thanks for the pictures, looks great.