H2 firewall

Last night me and a good friend were going to install a light bar on the front of my deuce. Unfortunately we were having a hard time finding where we can push the wires through the firewall. The light bar is sadly still in my garage we ran out of light last night gonna try again friday i think. So what i'm asking y'all for is where can i push some wires through my firewall?

There is a large rubber grommet that the main wiring harness runs through. It is really tight, but it is possible to run wires through it. If you look in one of my old threads it shows how I did it. My CB and roof light wires all run through it.

You can't do it at all, it's impossible, no way about it, uh uh. With that said, I'll make a fair offer on the light bar since you can''t use it anyway.......


Ok, go with what Scarsman said, he's probably right on the money. Just make sure to use a really good lubricant like KY Jelly if you're going to stuff something in that tight of a spot.......

seriously, my buddy keeps some in his garage for just these reasons

Yes, lube is your friend! I used dish soap, as it dries up.

Scarsman said:

There is a large rubber grommet that the main wiring harness runs through. It is really tight, but it is possible to run wires through it. If you look in one of my old threads it shows how I did it. My CB and roof light wires all run through it.

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Agreed, this is where my bundle of wires runs through for all my lights, switches, etc.

alaprova said:

Last night me and a good friend were going to install a light bar [...] we ran out of light last night

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The irony in this is not lost on me.

Scarsman where in relationship to the gas and brake pedal does the main wiring harness run though, im having a hard time.

There is also a large empty area well above this that you could simply drill through and put a grommet. This is what I did for all my wiring. I also sealed over the grommet from the engine side with Permatex Right Stuff to prevent any transfer of fumes into the cab.

I choose to do it this way on my H2 since I had a way higher chance of damaging a wires in the harness plug trying to get all my wires thru. That and this way I keep my accessories separate from my OEM plug.

To do it this way, remove the L-shaped bracket on the driver's side at the top rear of the engine compartment. This will give you access. You will see a black control box tucked high and to the right and your brake hydroboost to the left. You will need to remove a patch of insulation to see the metal. There is nothing behind this area in the interior of your H2. I have passed mulitple 5-7wire cables thru this area for winch controls, lights, lockers etc. and all is still clean, dry and functional after close to 10years! I have never had water come in and I have done water crossings over the hood of my H2.

A quick trick to make your own perfect grommets regardless of the wire size you are passing thru.

Once you have determined the exact location of the harness that will be passing thru the body, mark it and then pull out the shorter end of the wire harness you need to make the grommet for. Now take two auto-motive o-rings that fit snug to the harness, you want to be able to just barely be able to roll them along the wire. Place them close to your mark with slightly more gap than the thickness of the sheet metal you are going to pass thru. Now take a piece of heat-shrink tubing and cut it to a length that is 3/4inch longer than the placement of the o-rings you just installed. Now slide it over the wire and into position over the o-rings. Try to have 3/8inch past each o-ring. Now heat shrink it in place and you now have a sealed and safe grommet for your wires to live a long and happy life! You will need to use some dish soap or Windex to pass it thru with some ease!

You could/should add the silicone to add extra moisture protection and make sure to paint each and every hole you drill thru so you do not cause rust!

Hope this helps!

autumn walker said:

The irony in this is not lost on me.

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I had missed it the first time I read it!

alaprova said:

Scarsman where in relationship to the gas and brake pedal does the main wiring harness run though, im having a hard time.

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If you are looking at your pedals it is high and left. The harness is pretty big, like and inch or so I think.

I didn't use the factory wiring harness hole you guys are referring to. I drilled a hole somewhere down there and put in a grommet and it has worked fine. I have front and rear light wiring thru it...for what it's worth I'll take a look tomorow and post a pic

A great lubricant for running wires and dries up within a few moments of spraying is Silicone lubricant, I will try and take a picture of the one used. I work on the side with a company that sells and installs emergency equipment of Police, Fire, Undercover, and SWAT vehicles. And that is the lubricant we use, it even makes it easier to install grommets and even run the wires through them, as it lubricates the grommet to easily pull the wires.

I forgot about this thread...as promised here is a pic of where I ran my wires through. It's above the gas pedal, nevermind the crappy hole I put in the plastic firewall cover but I drilled a hole thru the firewall and put a grommet in, super easy and plenty of space to pull wires. It pops out in a great spot under the hood too.

^^ don't have anything to say.