Viair On Board Air Intallation

[Worley]

For those who installed the dual Viair 485C onboard air systems, you might want to replace the fuse block that came with it. Mine failed and killed both my batteries. It looks like the fuse got hot and melted then caused a bad connection that was arcing out. That fuse should have blown way before it caused that much damage. Luckily, I got the batteries covered under warranty. It appears that Viair changed to a different fuse block according to their online picture.

 

[Vigilance247]

For those who installed the dual Viair 485C onboard air systems, you might want to replace the fuse block that came with it. Mine failed and killed both my batteries. It looks like the fuse got hot and melted then caused a bad connection that was arcing out. That fuse should have blown way before it caused that much damage. Luckily, I got the batteries covered under warranty. It appears that Viair changed to a different fuse block according to their online picture.
View attachment 39762

Might want to increase the wire size to reduce heat. I had to have mine rewired.

 

[Worley]

Might want to increase the wire size to reduce heat. I had to have mine rewired.

I am using #8 wire. That’s plenty big for 60amp. According to Viair, max load for both compressors is 44amp. What size wire are you using?

 

[Vigilance247]

I am using #8 wire. That’s plenty big for 60amp. According to Viair, max load for both compressors is 44amp. What size wire are you using?

All I know is Viair told me the pumps pull 80 amps. Since the distance from the battery to the back of the truck was so long, a small wire would get too hot. So, Viair found a guy in my area to fix the original install. I took it to him and he doubled up the wires.

 

[CB68spc]

Rock Taxi were you able to connect the compressor positive cable to the stud on the cable clamp. The stud is too short on mine with all that metal bracket stuff that is attached to the short wire. No idea why they made it like that. Thought about using the clamping screw but it appears to be painted on the positive.

I used these for my winch install,
Don't remember where I ordered them but I think this would help.

Dual Battery Systems Made Simple – Unilug It! | Amelec Australia

Two Up battery terminal lugs are purpose designed for dual battery installations where it is not desirable to modify the factory battery leads or terminals.

amelec.com.au

 

[legmar]

I am installing mine as I type this. I currently have mine wired like this. The main power comes from the battery and the pressure switch goes to upfitter and relay. I will post pics of my mounting brackets I made later. View attachment 1540

What is the pressure switches used for? Wouldn’t it work the same just connecting 3 straight to an upfitter?

Wait… I think I figured it out. That pressure switch controls the on/off of the compressors based upon tank air pressure. I thought it was just a manual on/off button.

 

[Rock Taxi]

What is the pressure switches used for? Wouldn’t it work the same just connecting 3 straight to an upfitter?

Wait… I think I figured it out. That pressure switch controls the on/off of the compressors based upon tank air pressure. I thought it was just a manual on/off button.

You are correct. On / Off switch starts and stops the compressors, but pressure switch shuts off them when the power is on before you burn out the motors or blow the tank and air lines with too much pressure.

Ed

 

[Southocplumber]

Could you use and onboard air compress in line with train horn? So it was dual purpose?

 

[Rock Taxi]

Could you use and onboard air compress in line with train horn? So it was dual purpose?

You certainly can. You would tap into the tank for the supply of compressed air for the horns, and wire the horns however you like. It's on my maybe someday list to do just that.

Ed

 

[Worley]

I finally got around to redoing my Viar compressor setup. There was nothing wrong with the previous setup as it lasted 2 1/2 years underneath the truck just fine. I did have a few air leaks on the extended hoses to the tank, and I had to replace the 80 amp relay one time. I got tired of climbing under my truck to work on it (3 times) and bleeding the water out of the tank, so I journeyed on an 8 hour project to relocate my system. Makes perfect sense, right? Lol. I completely gutted my wiring, airlines, compressors and tank. I then installed everything to a builtright panel on the passenger side of my bed. I spent most of the 8 hours figuring out which way I wanted to mount everything. I think it turned out great and only sticks out about an inch past my wheel well. It is now out of the weather and hopefully will last longer. I removed the taillight and drilled a 1” hole through the bed and added a rubber grommet for the wire harness to feed through. I ran a 3/8” airline through an existing hole to my air horns. I did upgrade my power cable to 6 awg since it is a longer distance from the battery. Let me know your thoughts.