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McDisco
1st June 2008, 06:11 PM
Hey All

I had a failed attempt at trying to fit my new Firestone airbags yesterday. I bought them to provide just a little more support to the rear end on my Simpson trip (rear end of the car....no jokes about my rear end!). I jacked up the wheel, removed it and then lowered the disco onto the lowest part of the chassis and then un did the bottom shock mount so the axle would be at maximum droop. I also undid the top shock mount as I have Koni's and wanted to adjust the rebound.

I have OME heavy duty springs on the rear as I leave my drawer setup and fridge in the car always. Now the problem I encountered (and why it was a failed attempt) was that the installation instructions for the firestones tell you to squeeze the air out of the bags, stopper them and then wiggle them through the coils rungs to seat them. This is why I took the shock out etc so the space between the rungs would be maximised and installing the bags would be easier. When I went to try and get the bags trought he rungs it just wouldnt budge and I couldnt get them in. I think this is because they are heavy duty springs they are coiled tighter and hence more coils and the closer the coils.

I had already helped my brother in law fit his (he also has a disco) and his disco was in greater need of them as on our last big trip is back end sagged a lot more than mine. We put this down to the different rate springs in the vehicles. We managed to get his into place without too much hassle as the space between the rungs on his coils was larger. We didnt even need to remove the shock for greater droop.

So in an effort to get mine in I thought I would just removed the springs. I had borrowed a set of srping clamps and got to work trying to compress the spring enough to slip them out from the mounts. After a lot of screwing around I didnt seem to be getting anywhere. The clamps compressed the inner rungs but didnt seem to be making any difference to the tops rungs. By this time it was cold and dark (all the time taken up fitting my BIL's) and i had enough and gave up.

Anyway, my question is...is there an easier way to remove a spring or is there a way of flexing the spring enough that it will make enough room to slip the bag in?! I had though about going to the my mechanic and asking if I could put it up on the hoist and disconnect both shocks. This may let the whole axle droop enough to get the bloody bags in...

Any advice appreciated.

Cheers

Angus

Slunnie
1st June 2008, 06:19 PM
As per D2Au

lol! The trials and tribulations of working on suspension.
I support the chassis on stumps and if possible hang the whole axle,
as the suspension will resist articulation and minimise drop. [All do
gooders now close ears] I then stick a jack between the radius arm and
the chassis and jack the radius arm down on one side until the brake
lines run out of travel. There are then a couple of ways you can get
further drop by disconnecting the ABS line and unbolting the brake
lines or calipers etc - or use spring clamps. [Do gooders may now open
ears] Then pull the spring out, scruntch the polyair up and slide it
into the spring with the spacers and then reassemble.
(BTW, don't do this on the front without dropping the front Xmember)

Franz
2nd June 2008, 11:22 AM
As per D2Au

lol! The trials and tribulations of working on suspension.
I support the chassis on stumps and if possible hang the whole axle,
as the suspension will resist articulation and minimise drop. [All do
gooders now close ears] I then stick a jack between the radius arm and
the chassis and jack the radius arm down on one side until the brake
lines run out of travel. There are then a couple of ways you can get
further drop by disconnecting the ABS line and unbolting the brake
lines or calipers etc - or use spring clamps. [Do gooders may now open
ears] Then pull the spring out, scruntch the polyair up and slide it
into the spring with the spacers and then reassemble.
(BTW, don't do this on the front without dropping the front Xmember)
Angus,

When I fitted my airbags (and I have long springs) I did not need spring compressors. I simply undid the bolt of the control arm nearest the diff pumpkin and this will let your rear axle drop all the way down.

A WORD OF WARNING HERE THOUGH - be very careful not to let the axle drop too far as you may rip out the ABS and brake lines. You will need to jack the vehicle up, support the chassis on jack stands, undo the lower shock bolts, the top control arm bolt and then gently lower the rear axle down until the springs can be removed. Before loweering the axle, remove the bolts on the brackets that hold the brake lines (near the top of the shock towers) as this will give you slighty more droop.

Hope this helps.

Cheers,

Franz

100I
2nd June 2008, 05:11 PM
Disconnect the sway bar ;)

fatnold
2nd June 2008, 07:11 PM
I fitted mine in about 10mins each! Didn't even take off the wheel just jacked the body right up.I think the wheel still on helped stretch the springs out. Squash all the air out of the bag then plug the fitting. Put some lube (detegent on the bag to make it a bit more slippery).

All is not great however, the top blocks that they supply keep forcing their way out through the top of the metal coil seat. I look under the car and find the mounting rubber block is just bouncing around the air hose and the air bag is supporting the car directly against the coil seat! Does anyone have a solution to that?

Bigbjorn
2nd June 2008, 08:25 PM
Use a spring compressor with the jaws reversed so you can spread the spring and then the bag can be slipped in as per the illustrated installation instructions.

McDisco
2nd June 2008, 09:41 PM
Thanks all for the advice. Ended up following Simons's advice and alls well. Also disconnected the Koni's and adjusted the rebound.

The bags make a real difference...the disco corners like a sports car! woohoo!

Cheers

Angus

wardy1
2nd June 2008, 10:14 PM
G'day Fatnold..... you have obviously lifted your suspension. The firestones don't come with spacers but you cn buy the Polyair spacers from repco (bout $60/pair). these fit at the bottom of the spring under the bags. This then makes the bags the right length to keep the top blocks in.:)
Better still, the bottom shock bolts don't rub on the bags.