VOLVO 700-SERIES FRONT BUSHING REPLACEMENT
by Ian Giles
Welcome to the back yard and big hammer course on suspension
bushing replacement.
Just kidding all, to add a little credibility to this procedure,
I am a Certified Journeyman Mechanic and have worked in the auto industry for
over 15 years, but that was in a past life. Like you, I now have to rely on making
do in my backyard garage and my available hand tools, rather than walking across
a shop to the $$$ press, hoist, or special tool number ###.
As I said, with a little ingenuity and patience most repair work can be performed at home, so let
us begin. There are three front suspension bushings on each side of the 700 series
Volvo, an inner lower control arm bushing, an inner strut rod bushing, and an
outer strut rod bushing, the outer strut rod bushings are split into two cone
shaped halves. Both inner bushings are steel sleeved, that is, an external steel
sleeve or tube with a smaller steel tube center bonded together with rubber.
Currently
polyurethane bushings are not available for the Volvo 700 series, but new rubber
bushings will drastically improve the suspension compliance for aggressive street
to mild competition driving. Bushing kits are available through any Volvo dealer
or iPd where I purchased mine.
You will need a few tools they include:
- Jack and jack stands
- Sockets and wrenches (assorted sizes)
- Hacksaw Hammers (several large)
- Mechanics vice (mounted to a work bench)
- Propane torch (may be needed)
- Bench or side grinder
- Safety equipment, goggles, gloves
- Lock-tite
- Hot bath or Jacuzzi (a requirement when the job is finished)
Removing the suspension components:
- Raise and support the front of the vehicle, make sure you use jack stands
positioned under the frame, this allows the suspension to hang.
- Remove the front wheels
- Remove the cotter pin in the lower ball joint and then remove the ball joint
securing nut.
- Remove the bolts securing the sway bar to lower control arm, the inner lower
control arm, and inner and outer strut rod. I would suggest that you complete
one side at a time so you can refer to the opposite side if needed.
- Pull the lower control arm out of the cross member and the strut rod out
of the body bracket, then pull the strut rod out of the lower control arm.
Now the lower ball joint must be separated from the control arm. The ball
joint uses a tapered shaft that fits into a corresponding tapered hole in the
control arm, there are two methods to loosen this fitting. The first and easiest
method is to use a ball joint separator, this is a special tool available at
most rental companies that is placed between the lower control arm and the ball
joint and then hit with a hammer. This action forces the ball joint apart, the
problem with using this tool is that it often tears the rubber cover on the
ball joint. If this happens you have to replace the ball joint, but there is
another way.
If you strike the side of the control arm at the point where the ball joint
shaft passes through the arm very hard with a hammer, the connection will loosen.
You must strike it HARD and don't miss or you will strike the threads on the
ball joint, which will also result in a ball joint replacement. Also do not
hammer on the ball joint nut trying to hit out, this will flatten the threads
and ruin the joint. This method works very good on steel lower control arms
(a magnet can be used to check this), if your control arms are aluminum or alloy
position a hammer on the control arm opposite the ball joint and then strike
this hammer with another hammer. As soon as the control arm is loose it will
fall to the ground
Removing the bushings
The outer strut rod bushings are the easiest to remove, simply pry them out
with a large screwdriver or you fingers. If they are like mine there will be
a lot of corrosion on the control arm that must be removed, use a small hammer
and chisel, a file, or a wire brush on a drill to clean the area.
Removing the inner strut rod bushing is a little more challenging. You will
notice that the bushing sleeve extends past the strut rod on both sides, the
easiest way to remove this bushing is to grind one side of the bushing, rubber
and metal sleeves, flush with the strut rod. Using a bench or side grinder grind
the bushing flat being careful not to grind any of the strut rod.
Now the fun begins, support the strut rod in the open jaws of the vice, do
not clamp the strut rod, instead adjust the jaws so the bushing sleeve will
not hit the jaws but the round end of the strut rod is support by the vice jaws.
Using a hammer and socket, or a pipe, with an outside diameter slightly smaller
than the outside diameter of the bushing try pounding the bushing out. Remember
to wear safety goggles and gloves. With luck and a strong arm the bushing will
slowly come out. Sometimes the rubber will separate from the outer sleeve and
come out separately, this is OK, I will explain how to remove the outer sleeve
a little later. If the bushing will not come out the next method is to carefully
heat the round end of the strut rod with the propane torch, do not use a welding
or brazing torch because too much heat will ruin the strut rod. Heating will
cause one or two things to happen, first the round end of the strut rod will
expand slightly making the bushing easier to pound out. Secondly the bond between
the rubber and outer sleeve will loosen and allow the bushing to be removed
but leaving the outer sleeve in the strut rod.
If the bushing separated leaving the outer sleeve, removing this sleeve is
easy. By removing the blade from a hacksaw, place the blade through the center
of the sleeve and then reinstall the blade to the hacksaw frame. Carefully cut
through the sleeve being very careful not to nick or cut into the strut rod.
Once the sleeve is cut it can easily be removed by tapping with a hammer and
chisel.
Removing the control arm bushing is the same procedure as above. Grind the
bushing flat with the control arm, you will also have to grind a flat spot on
the outer bushing sleeve where it flares out so the control arm can be supported
in the vice. This bushing usually pounds out easier and in one piece. Heat can
be used but do not overheat the control arm, avoid heat if the control arm is
alloy or aluminum. Finish off by cleaning all parts.
Installation
- Lubricate the bushing and control arm / strut rod with WD40 or equivalent.
- locate a pipe or socket large enough that it pushes only on the outer sleeve.
The bushings can be pressed in by using the pipe / socket and slowly tightening
the jaws of the vice, or if your vice is not large enough the bushing can
be hammered in using the appropriate pipe / socket as a driver. Be careful
to drive the bushing in square and try to avoid damaging the outer sleeve,
although minor damage will not effect the performance.
Reassembly
- Reinstall the strut rod into the control arm with the new bushings, do not
tighten the bolt.
- Install the control arm and strut rod into their mounts on the cross member
and frame, install the bolts but again do not tighten.
- Insert the ball joint stud into the control arm. Place the jack under the
outer end of the lower control arm, leaving room to access the nut on the
ball joint, raise the jack until the weight of the vehicle is on the jack
(lift the control arm until the car lifts just off the jack stand). This procedure
is important because it places the new bushings in an unloaded position when
the suspension is weighted, then as the suspension moves through compression
and rebound the bushings will flex equally in both directions. If the bushings
are tightened when the suspension in hanging, the bushings will be over-flexed
in one direction and will fail quickly.
- Place some lock-tite on all threads and tighten all nuts and bolts, then
insert a new cotter pin in the ball joint stud.
- Repeat this entire procedure on other side and congratulations you have
just installed your own front bushings. At this point you will either feel
incredible pride or a realization why mechanics charge so much.
- Have a hot bath or Jacuzzi and enjoy a car that will feel like new.
Good luck all! |
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