Mounting ARB Air Compressor

[shadowmoto17]

Finally got my ARB twin mounted up over the course of the last couple days. Went with the ARB under seat mount and designed/built myself a manifold out of parts that I sourced mostly from McMaster-Carr. Happy with the way it turned out, though I still need to fab up some brackets for the outlets which will be mounted under each of the front seats.

I repurposed the ARB switch/outlet bracket to instead hold a pressure gauge. I tied the switch illumination into my dome light circuit so it lights up for me when I open the door to use it, but it won't remain lit while I'm driving at night.

It is tied into a pressure regulator on one side of my manifold. The other side of my manifold has a ball valve installed in it. This will allow me to air up/down all four tires at once via double ended hoses that will attach to the outlets on either side of the Jeep.

And since there seems to be a lot of concern about modifying the air vent, here's a picture of what's going on under there. The directions tell you to cut off 200mm (just shy of 8 inches), but that's not absolutely necessary (depends on your manifold configuration) and will leave your vent pretty much even with the rear of the body tub crossmember that it's mounted to. I also chose to graft the diffuser nozzle back onto the end of my vent to help spread out the air flow. Overall I think I'm at about 125mm (5inches) shorter than the stock vent configuration.

Do you have to have the manifold or is that just for lockers? I plan to do that in the future, but for now just upgrading my air compressor for tires. When I was talking to Northridge4x4 they made it sound like the manifold is optional if you're not planning on using it for lockers.

Sponsored

 

[tonygiotta]

Do you have to have the manifold or is that just for lockers? I plan to do that in the future, but for now just upgrading my air compressor for tires. When I was talking to Northridge4x4 they made it sound like the manifold is optional if you're not planning on using it for lockers.

Yes, and no. ARB really doesn't supply anything with the compressor other than some hardware to mount it with. They leave it up to you as to how you want to plumb it. If you want to keep it very basic, you can just screw an air outlet into the 1/4" NPT port on the compressor and away you go. (Keep in mind this is not an option if you're using the under seat mount as there is not enough clearance.) If you want multiple outlets, an air tank, or lockers, etc, you need a way to route the air to them. This is going to involve a "T" at the very least. Since my set-up involved 5 different in/out connections, it was just easier for me to use a fixed manifold than it would have been to string together a series of "T's".

It's worth mentioning that the ARB manifold has the benefit of acting as a VERY small air tank as well so that you can activate your lockers without having to wait for the compressor to build pressure each time. If air lockers are in your future, it may be worth adding now so you don't have to re-plumb your system later. If they're not, the ARB manifold is not worth the added expense and bulk.

 

[Call911man]

I built my own and used a an insulated aluminum heat shield on the exhaust side and had no problems for about 9 months until I added the coilovers, my bracket no longer worked. The new bracket sits higher and further from the exhaust and also includes a heat shield. MCJA's install is beautiful and very well done, tempting to replicate given the wonderful write up (Thank you)! 60s are in my future with air lockers, the occasional pump noise would drive me crazy inside. However, the tank he used would minimize that a great deal. I will be sure to let you all know if my compressor fails. Given the the dual compressor sides are independent from the battery to each compressor motor, i'd expect to see a failure from the side closest to the exhaust first and hopefully not leave me limping back to civilization on 6psi. Understanding that the relay for each compressor side is still a single point of failure that I could wire past if I had to.
Thanks ocenablue2019, great points.

 

[Call911man]

I just met Ben at Varozza 4x4 Outfitters. He’s making a pretty slick under hood mount. The new washer tank is smaller but its a nice location and i can tell you, with the evo coilovers, the under booster was a pain to install plus, Ben’s design is up front and away from the exhaust.

https://www.varozza4x4.com/products
Send him an email and tell him Kent sent you. [email protected]

V4x4JLCOMP
“Jeep JL Wrangler and JT Gladiator air compressor mounting kit for ARB twin compressor. This bracket kit mounts your compressor under the hood where it belongs. Easier battery access for wiring and no extra heat or noise inside the cab. Works with stock or aftermarket inner fenders and standard coil suspension or coilover mounts. No drilling required, mounts to factory holes. Requires removal of factory windshield washer reservoir. Kit comes with a new smaller reservoir that accepts the factory pump and low washer fluid sensor.”



[/QUOTE]

 

[shadowmoto17]

Yes, and no. ARB really doesn't supply anything with the compressor other than some hardware to mount it with. They leave it up to you as to how you want to plumb it. If you want to keep it very basic, you can just screw an air outlet into the 1/4" NPT port on the compressor and away you go. (Keep in mind this is not an option if you're using the under seat mount as there is not enough clearance.) If you want multiple outlets, an air tank, or lockers, etc, you need a way to route the air to them. This is going to involve a "T" at the very least. Since my set-up involved 5 different in/out connections, it was just easier for me to use a fixed manifold than it would have been to string together a series of "T's".

It's worth mentioning that the ARB manifold has the benefit of acting as a VERY small air tank as well so that you can activate your lockers without having to wait for the compressor to build pressure each time. If air lockers are in your future, it may be worth adding now so you don't have to re-plumb your system later. If they're not, the ARB manifold is not worth the added expense and bulk.

I was thinking about the air tank that arb has also and mounting that under the Jeep since in the instruction it recommends that but I’ll do that in the future and if I think I really need it. The manifold just arrived in the mail yesterday so it will be installed with the compressor but won’t be getting utilized till later on when I upgrade the axles and with them air lockers. One of the setups I read made sense for the under passenger seat location but if it does bother me for the possibility of submerging it I’ll move it to the back of the Jeep. I did read through the the instructions and found it interesting all of the recommendations such as not putting close to the engine because of the heat, so it makes me wonder for all those that complain about their compressor quitting on them due to the location where they have it.
regardless hope to install it this weekend if the under seat bracket comes in.

 

[SmoothJeepOperator]

So I have the single arb mounted under the hood. Anyone know if I would have to worry about battery draining by running it with the engine off? Ran it with the engine in yesterday and it got pretty hot to the touch.

 

[Chocolate Thunder]

So I have the single arb mounted under the hood. Anyone know if I would have to worry about battery draining by running it with the engine off? Ran it with the engine in yesterday and it got pretty hot to the touch.

Not if you run it for just a few minutes, like to air up 1 set of tires. Obviously extended running will run down the battery on a vehicle that’s not running.

 

[SmoothJeepOperator]

Not if you run it for just a few minutes, like to air up 1 set of tires. Obviously extended running will run down the battery on a vehicle that’s not running.

Good idea. Maybe I'll do two with the engine off and then start it back up and do the last two. Definitely too hot to just leave the engine on.

 

[Chocolate Thunder]

Good idea. Maybe I'll do two with the engine off and then start it back up and do the last two. Definitely too hot to just leave the engine on.

You can do all 4 on 1 Jeep. I have a twin and I’ve aired up all 4 from 15 to 33 with the engine off to test it. Or you could pop the hood while airing up if you’re going to run for an extended time airing up multiple vehicles.

 

[SmoothJeepOperator]

You can do all 4 on 1 Jeep. I have a twin and I’ve aired up all 4 from 15 to 33 with the engine off to test it. Or you could pop the hood while airing up if you’re going to run for an extended time airing up multiple vehicles.

I went from 18 to 37 on all four. Turned the Jeep on once and then back off quickly. Worked perfectly.

 

[Call911man]

So I have the single arb mounted under the hood. Anyone know if I would have to worry about battery draining by running it with the engine off? Ran it with the engine in yesterday and it got pretty hot to the touch.

Here is a link to the ARB spec sheet. https://www.arb.com.au/assets/air-lockers/6-07.pdf
Pick your model and do the math. One thing to be aware of, with the alternator not running and a load such as the CKMTA12 Dual compressor that many of us use, pulling the stated amperage of 50.4 AMPS under load , the battery voltage can drop below 12 volts while under that load pretty quickly. As voltage drops, the amperage increases and the motor becomes increasingly less efficient. This could result in creating the heat you are trying to avoid. The converse is also true, when voltage goes up, current (Amperage) drops and the motor is provided more power (Voltage) to do it's job. With the Jeep running, you are likely to see more around 14 volts

The single CKMA12 version that I guess you are referencing, pulls 25.2 amps at 12 volts under load.

It might be worth while to inflate all 4 tires from your off road pressure to street pressure with the engine off and measure the voltage at the battery as you go.

I did a quick test on my JL with the key off, dual compressor (CKMTA12), (no load 28.4 amps@12 volts per chart). The voltage dropped .5 volts as soon as I turned the compressor on. Then with the compressor running, I started the Jeep, within a few seconds, the compressor speed increased noticeably demonstrating the increased voltage affect on the compressor. Understanding that the ARB compressors include both current and temperature overload protection built in, I choose to operate with the Jeep running, providing a higher voltage to the compressor.

 

[SmoothJeepOperator]

I did notice the compressor wasn't working as well on the last tire, had my wife fire up the engine and it picked right up. A lot less scientific than what you did but pretty much the same thing. Btw I have the single.

 

[Halstem1]

Good idea. Maybe I'll do two with the engine off and then start it back up and do the last two. Definitely too hot to just leave the engine on.

question because I've been eyeing this under the hood spot for a single... Was the engine hot or the compressor was hot? or both?

I think my engine is super hot but I'm not sure what to compare it to. I tried to empty my catch can after the vehicle had been off for about an hour.... it was still too hot to touch.

Out of curiousity I was using an infrared thermometer to check temps up high compared to down in the fender well where everyone says its too hot because of cat. The fender well area was significantly cooler than the top of the engine. Still not sure I want to mount a compressor there, but thought that was interesting.

 

[SmoothJeepOperator]

question because I've been eyeing this under the hood spot for a single... Was the engine hot or the compressor was hot? or both?

I think my engine is super hot but I'm not sure what to compare it to. I tried to empty my catch can after the vehicle had been off for about an hour.... it was still too hot to touch.

Out of curiousity I was using an infrared thermometer to check temps up high compared to down in the fender well where everyone says its too hot because of cat. The fender well area was significantly cooler than the top of the engine. Still not sure I want to mount a compressor there, but thought that was interesting.

I think both are hot, but I didn't do much investigating honestly. All I know is yesterday I drive about 30 minutes to the beach, drove around on the beach and then parked to air up and it was too hot to disconnect the air hose with my hands. I got a bunch of paper towels and got it off. I piyti the hose on the passenger side floor and put the ac on and it was mostly cool when I got back to my vacation spot.

Today I drive out and into the beach and hung out for a few hours when I aired up today it wasn't nearly as hot as The previous day. Not even hot to touch. So could be that the cat had alot more time to heat everything up yesterday and today I let things cool first?

 

[47Jeepster]

Bought and installed the Grimm ARB Dual Compressor Bracket. A little pricey, but great quality and well engineered. Loved it for about one week. That's when I went to install my Metalcloak inner fender liner and found that the two are not compatible. Discovered that it's only guaranteed to fit behind the OEM fender liners. Opps. In all fairness, Grimm did mention this problem down (way down) in the fine print:

"This bracket kit will fit with stock inner fenders in place. It has not been tested with aftermarket inner fenders."

Had sold my compressor in a box, so needed a quick fix. Bought the M.O.R.E. bracket, that I've been avoiding forever. Also found a main power extension harness that made the installation much easier: https://www.amazon.com/gp/product/B07MJHX6SL/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1 Removed a connector from the extension harness to fish the harness under the carpeting and out through the floor plug over the fuel tank. Then removed a connector from the ARB power harness to fish it down along the firewall to the frame. Once the two harnesses were in place I reinstalled the two connectors and joined them together. Could have soldered the ends together, but the connectors are waterproof, so left them in place.

Not elegant, but a reasonable solution.

Sponsored