AGM battery and air compressor under vehicle?

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ryno9562

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Hey all. I have a 2003 Xterra with a rear tire carrier so I could relocate my spare from underneath and there is a good bit of space now available under the rear behind the rear axle that I would like to utilize. I want to mount a 2nd battery (AGM) and an ARB air compressor(possibly the twin) under there but my concern is when I come across the occasional water crossing will either be damaged in the process? Keep in mind I do not for see any of said water crossings to ever be salt water so not super concerned about salt corrosion. I will definitely make sure the compressor has an extended breather which I will probably route into the cab. These vehicles are not the biggest on the inside so trying to make sure I can utilize as much space as possible inside for other items. Any help will be greatly appreciated thank you.
 

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The battery wont care.
I know people mount the ARB under the hood and they do well but I would email them about it being submersed. At minimum as you noted, extend the air input. ARB says the compressor is water resistant, not water proof. I remember reading about another manufacture listing their compressor as water proof but don't remember who it was.
What you don't want to have happen is several years from now the compressor internally corrodes because someone on a forum said they have theirs mounted under the vehicle and they have no problems. If someone honestly said they did this years ago, submerge it regularly and have no issues, then I may be inclined to try it. I would however pull it out every now and then, pull the case apart and inspect it.

My compressor is mounted behind my passenger rear panel. The cavity is big enough to disperse the heat. The compressor is around 10 years old.

On a similar note, the number one reason a winch doesn't work when you need it is due to a slight amount of moisture intrusion into the motor.
 
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ryno9562

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The battery wont care.
I know people mount the ARB under the hood and they do well but I would email them about it being submersed. At minimum as you noted, extend the air input. ARB says the compressor is water resistant, not water proof. I remember reading about another manufacture listing their compressor as water proof but don't remember who it was.
What you don't want to have happen is several years from now the compressor internally corrodes because someone on a forum said they have theirs mounted under the vehicle and they have no problems. If someone honestly said they did this years ago, submerge it regularly and have no issues, then I may be inclined to try it. I would however pull it out every now and then, pull the case apart and inspect it.

My compressor is mounted behind my passenger rear panel. The cavity is big enough to disperse the heat. The compressor is around 10 years old.

On a similar note, the number one reason a winch doesn't work when you need it is due to a slight amount of moisture intrusion into the motor.
What do you drive? Is it a Gen 1 Xterra like mine? If so do you have pictures of the mounting location?
 

smritte

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Sorry no. I have a 96 Cruiser. I have it mounted to a treated wood platform. My VIair 450 takes up way more room then your ARB. You should have an easier time mounting yours. One of my friends mounted his ARB under the front passenger seat. I'm waiting to see how that works out. My only concern there is heat but I doubt it will be an issue. The nice thing about the ARB is its pretty much a square. That gives you more mounting options.
 

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Hey all. I have a 2003 Xterra with a rear tire carrier so I could relocate my spare from underneath and there is a good bit of space now available under the rear behind the rear axle that I would like to utilize. I want to mount a 2nd battery (AGM) and an ARB air compressor(possibly the twin) under there but my concern is when I come across the occasional water crossing will either be damaged in the process? Keep in mind I do not for see any of said water crossings to ever be salt water so not super concerned about salt corrosion. I will definitely make sure the compressor has an extended breather which I will probably route into the cab. These vehicles are not the biggest on the inside so trying to make sure I can utilize as much space as possible inside for other items. Any help will be greatly appreciated thank you.
ARBs have a high pressure cutoff switch that I suppose could be omitted but I would be nervous about mounting it under the vehicle because of electrical connections and water. Its going to get pelted with dust in that spot and I imagine that is not good for it (nor would a rock hit be good for it). Have you looked under the hood or maybe under a seat for a good mounting spot that would keep it cleaner/dryer? Are you thinking of running a permanent air hose from the compressor to a more accessible location? I have a single mounted under the hood and it gets hot from the engine heat alone; maybe next time I'll be looking to keep it in the bed or cab of my truck.
 

North American Sojourner

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The road rash under there would be EPIC. Add to that the physical abuse and water damage possible? I would not. I've done some racecars with the transmission cooler and fan in the rear and after several runs down the track it's covered with rubber, oil, fuel, water from the burnout, and other things.
 
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M Rose

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The ViAir compressors are both water proof and dust proof. I wouldn’t hesitate to mount it under the Ex where the spare tire was. As for an AGM deep cycle mounted under there, get a Marie battery box and vent it at the top and incorporate a one way drain valve at the bottom and you will be fine.
 
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John and Mandi

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We had an AGM mounted under our van on a skid plate that was installed where the factory spare used to be, no issues. We carry a portable Viar air compressor but friends of our that had an ARB installed under their truck had it fail after about three years. It was cleaned and rebuilt by a Bosch service center but only lasted another 6 months so they had to bring back a new one from the US when they visited family. The amount of dust, dirt, and debris was just too much over the years. We both were full time so our rigs saw a lot of dirt tracks and extreme changes in weather.
 
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