Part 2: Mounting the Air Compressor and Tank
Mounting the air tank and compressor was as easy as finding the
right spot in the small open area opposite the muffler. Even so, it's
still a game of trial and error. Access to an auto lift would have been a
nice amenity, but my dad's Bone creeper and some large floor jacks
made the job tolerable. I positioned the compressor as shown in the
photos, with two of its "feet" bolted to a lip in the frame cross member
and the other two feet on a steel plate I made from the pile of scrap
metal at my disposal. Another piece of steel plate was cantilevered
out from the underside of the cross member to support the plate. This
required basic metal fabrication, plenty of measuring for drilling bolt
holes, and a good drill for securing sheet metal bolts to the frame.
While metal fabrication might sound intimidating for anyone who
hasn't done it, the drill press and band saw made it easy. All my cuts
were pretty much square, no welding was needed, and the end result
was a very solidly mounted compressor. The angle of the support
plate is somewhat odd partly because of the shape of the frame - not
so much flat and straight - which put limits on where the plate could
be mounted flush. Also, I needed to avoid the torsion bar bolt. And
then there's the laziness factor - a couple existing holes in those
particular pieces of steel just happened to line up pretty well at that
particular angle.
Next up was the air tank. I had to stray from what is probably the
recommended mounting for the tank because of two factors: 1) the
frame bowed outward within the space I had to work with, making a
direct flush mount impossible; and 2) the rear brake lines were
routed along the inside of the frame. I really didn't want to disturb the
brake lines, so I worked around them. As I mentioned, the goal was
to mount the tank as high up under the frame as possible, which
meant rotating the tank 90 degrees. With this, I needed to fabricate
some more metal supports that would hold the tank on its side, as
close to the frame as possible. The photos show how I did this - the
front side of the tank support bracket sits flush against the frame; the
rear support bracket has a couple-inch gap between the frame. Here
again, the shape of the underside of the frame didn't allow for flush
mounting of a support plate directly across from the tank's rear
bracket, due to the frame's curvature as it extends toward the rear
axle. As with the compressor support plate, I had to go at it from an
angle, using angle iron to get some extra strength for the length I had
to cover. The angle iron reduces clearance under the frame by an
inch or so, but it's still no lower than the leaf spring pivots or the
Westin step bar.
Overall, I could not have been more pleased with how the tank and
compressor fit within this space. Unless someone sticks their head
under the Blazer, they'll never know what's there. Combined with the
stealthiness of the horn mounts, this is a relatively uninspiring
add-on for those interested in taking your ride. And best of all, nobody
will ever expect 150 or so decibels coming from this vehicle.
Now it's time to make everything work.
Mounting the air tank and compressor was as easy as finding the
right spot in the small open area opposite the muffler. Even so, it's
still a game of trial and error. Access to an auto lift would have been a
nice amenity, but my dad's Bone creeper and some large floor jacks
made the job tolerable. I positioned the compressor as shown in the
photos, with two of its "feet" bolted to a lip in the frame cross member
and the other two feet on a steel plate I made from the pile of scrap
metal at my disposal. Another piece of steel plate was cantilevered
out from the underside of the cross member to support the plate. This
required basic metal fabrication, plenty of measuring for drilling bolt
holes, and a good drill for securing sheet metal bolts to the frame.
While metal fabrication might sound intimidating for anyone who
hasn't done it, the drill press and band saw made it easy. All my cuts
were pretty much square, no welding was needed, and the end result
was a very solidly mounted compressor. The angle of the support
plate is somewhat odd partly because of the shape of the frame - not
so much flat and straight - which put limits on where the plate could
be mounted flush. Also, I needed to avoid the torsion bar bolt. And
then there's the laziness factor - a couple existing holes in those
particular pieces of steel just happened to line up pretty well at that
particular angle.
Next up was the air tank. I had to stray from what is probably the
recommended mounting for the tank because of two factors: 1) the
frame bowed outward within the space I had to work with, making a
direct flush mount impossible; and 2) the rear brake lines were
routed along the inside of the frame. I really didn't want to disturb the
brake lines, so I worked around them. As I mentioned, the goal was
to mount the tank as high up under the frame as possible, which
meant rotating the tank 90 degrees. With this, I needed to fabricate
some more metal supports that would hold the tank on its side, as
close to the frame as possible. The photos show how I did this - the
front side of the tank support bracket sits flush against the frame; the
rear support bracket has a couple-inch gap between the frame. Here
again, the shape of the underside of the frame didn't allow for flush
mounting of a support plate directly across from the tank's rear
bracket, due to the frame's curvature as it extends toward the rear
axle. As with the compressor support plate, I had to go at it from an
angle, using angle iron to get some extra strength for the length I had
to cover. The angle iron reduces clearance under the frame by an
inch or so, but it's still no lower than the leaf spring pivots or the
Westin step bar.
Overall, I could not have been more pleased with how the tank and
compressor fit within this space. Unless someone sticks their head
under the Blazer, they'll never know what's there. Combined with the
stealthiness of the horn mounts, this is a relatively uninspiring
add-on for those interested in taking your ride. And best of all, nobody
will ever expect 150 or so decibels coming from this vehicle.
Now it's time to make everything work.
| Two compressor feet on the frame cross member; two compressor feet on 3/16" steel |
| More 3/16" steel for under-support |
| Making good use of scrap steel |
| My work will never be mistaken for that of a professional. Note the missing bolt in the flat piece of 3/16" steel - sometimes you just get sick of drilling 4 bolt holes when 3 will do just fine. |
| All connectors connected. The black hose is the compressor air intake, which is routed along the drivers side frame rail and under the hood, where it connects to the filter. |
| Onboard Air! |
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