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Introduction
The Saab 9000's engine is mounted to the subframe on two hydraulic mountings,
with a third rubber mounting under the transmission. A torque control arm connects
the top of the engine to the body of the car, limiting movement at the top.
While the transmission mounting seldom gives trouble, the hydraulic engine mountings
have a tendency to fail, resulting in excessive movement and noise, difficulty
in changing gear, excessive wear on the upper torque arm which eventually results
in failure of the upper torque arm bushes, and eventually, exhaust failure.
These are often, but not always, accompanied by "clunking" sounds
while moving off. My car was clunking badly, and getting rapidly worse, and
I could feel the gear linkage rubbing while changing gear. Engine noise and
road noise were considerable, and I assume they were being transmitted directly
from the engine to the subframe by the metal-to-metal contact allowed by the
failed mountings.
I gained the confidence to tackle this job from Quasi's
web site, where he has published a procedure for engine mounting replacement
on his 1991 9000. However, I found some different ways of doing things, perhaps
related to my car being a "new shape" 9000 (1996), and so deemed it
useful to publish my own account.
This procedure assumes you will be replacing both engine mountings. Since much
of the work involved is common to replacing both mountings and since the rear
engine mounting often fails shortly after failure of the front engine mounting,
it makes sense to replace both at the same time.
Note
You may wish to consider applying the engine mounting modification documented
at the Townsend Imports web site
prior to installation. I didn't modify the mountings.
Time required
Naturally, this will vary with both the individual and what they find when
they get there. However, this took me about two hours. This was my first time
and I imagine I could do it again in less time, barring any unforseen holdups
and given the use of a longer socket extension (see below). I won't be spending
time taking notes and photographs, either (well, maybe some photographs, as
I'm sure I could improve on those shown here).
Tools required
I assume some basic tools, such as a jack, axle stands, socket set, etc. However
I do not assume you will already have all the necessary metric socket and spanner
sizes, especially if you are in the USA. Here is a list so you can make sure
you have all the necessary sizes before you start.
Spanners
Sockets
- 8mm
- 10mm
- 13mm
- 14mm
- 16mm
- 17mm
Other
- It is desirable to have a 24" (at least) socket extension, or two 12"
extensions
Procedure
- Jack up the front of the car and place it on axle stands. If you are not
sure where you can safely place the jack and axle stands on a 9000, go here
for more information.
- Remove the front right-hand roadwheel.
- Remove the right front inner wing liner, documented here.
- Unscrew and remove the 16mm bolt securing the top of the front engine mounting
to the engine bracket.
- Unscrew and remove the 16mm bolt securing the top of the rear engine mounting
to the engine bracket. On my car this bolt was already loose! This bolt is
a little tight to get to. You'll need a small ratchet (socket wrench) and
a short extension.
- Remove the bolts securing the upper torque control arm using a 16mm spanner
and 16mm socket and remove it. It may be necessary to remove the power steering
fluid reservoir from its mounting to gain access (mine simply slid upwards
and off). On my car, the front bolt will not slide all the way out. However,
it is not necessary to remove it completely, as the torque arm is slotted
on one side to clear the bolt. I have read that the front bolt comes out completely
on earlier models and it is necessary to do this on these models to remove
the arm.
- Raise the engine slowly by either securing an engine hoist to the lifting
eyes on top of the engine, or by jacking up the sump using a sturdy piece
of wood to spread the load and avoid damage. Watch both above and below for
anything that might be straining as you raise the engine and keep going as
far as it will go without straining. I have not used a hoist, nor know what
precautions are necessary. With a jack, however, place blocks or some other
support underneath the engine to support the engine in case of jack failure.
I wedged a convenient concrete block under the transmission end of the engine.
Remember, you will probably be getting your hands between the engine and the
mountings and you don't want the engine falling at that point!
- Remove the two 13mm bolts securing the front engine mounting to the subframe.
While the rear bolt is easy to remove, the front bolt is harder to get at.
The easiest way is to use a 24" socket extension (or two 12" extensions)
and access the bolt from above the engine compartment. Since I only had a
singe 12" extension, I used this to undo the front bolt from under the
wheel arch, with about 30 degrees of movement. Both bolts were a little tight
due to some corrosion
- Wriggle the front mounting out of the subframe. This is what mine looked
like (under stress). The rubber has separated.
- Wriggle the new front mounting into the subframe and refit the bolts. I
applied copper grease (anti-seize compound) to the threads to ease refitting
and subsequent removal. Torque the bolts to 30Nm (22lbft).
- Using a 17mm socket underneath, a 13mm socket or spanner above for the front
bolt and a 14mm socket or spanner above for the rear bolts, remove the three
bolts securing the rear mounting to the subframe.
- Slide the rear mounting forwards and out of the subframe. Here is my old
rear mounting (again under stress). Again, the failure is obvious.
- Slide the new rear mounting into the subframe and refit the bolts and nuts.
Torque the bolts to 30Nm (22lbft).
- Carefully lower the engine. Watch the alignment of the engine brackets
on the engine mountings. I had to stop and lightly tap the top plate on the
front mounting to get it to locate in the engine bracket. The rear bracket
settled on its mounting without intervention.
- Refit the two 16mm bolts to the top of the engine mountings. Torque the
bolts to 40Nm (30lbft). The top plate of the mounting
is keyed to the engine bracket to stop rotation, so there is no risk of damaging
the rubber by twisting it.
- Refit the upper torque control arm and the power steering reservoir.
- Replace the inner wheel arch liner as described here.
- Refit the roadwheel.
- Lower the car.
- Torque the roadwheel bolts to 115Nm (85lbft).
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