Spring Assister Air Bladders
Neil Matthews and I got stuck into his 2001 VX at
the weekend. Neil had a full ARB OME suspension - 880/891
springs, but wanted the back to sit up a bit more when fully
loaded for the big trips. Already has too many dings in the tank.
He's happy with the way the suspension performs when unladen, and
didn't want super heavy duty springs.
Polyairs seemed the best solution because of their
adjustability. The cost of $220 a set was pretty reasonable.
Installation is pretty straight forward, but you
have to be very careful about safety issues, and ensure vehicle
chassis is well supported on stands, wheels chocked etc.
Don't want to become as statistic.
We tackled it according to the instructions but
offer the following additional suggestions:
#1 We have installed the valves inside the
LH rear of the vehicle (photo). This was the better side as
it keeps the polyair hoses away from the hot exhaust. There's
an area of well protected space behind it.
#2 We drilled a 15m hole in the middle of
the bumpstop - the instructions said 40mm which looked excessive.
#3 Need to cut a few rungs off the centre
bump stop - we left an extra rung in because the vehicle was
lifted. See photo. This is critical to the performance
of the polyairs. Hacksaw cuts it nicely. Other option
is to measure up beforehand, and calculate where to cut.
#4 Do the RHS polyair first - routing the
hoses will be easier.
#5 We reinforced the join between the hose
and bag with a 20cm length of split hose,
and taped it closed. Have heard of problems
at this join, so an ounce of prevention....
#6 Put a Coopers Ale on ice and crack it
open when you've finished.
#7 We protected the polyair hose with
convoluted split tubing, to protect against exhaust heat, as well
as stones etc and routed the hose over the top of the crossmember.
Held by cableties - not too tight - don't want to squash the tube.
#8 Have enough slack in the air tubing so
the bags are free to sit low in the spring.
When its all done, Measure the rear lift (lower
rim to guard) with no air, then with 25psi. We found a 10mm
difference when unladen, which I think is about right - when
loaded, the difference becomes much greater. Let the
polyairs down to 5psi, until you need them. Those digital
tyre gauges are great for measuring these low pressures - normal
gauges don't go below 10psi.
Now, Jeff M, Geoff H, and Dave T can get to work!!