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Fitting Polyair
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!!

Cheers
Phil
2002 GXLTD

 


 

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