|Hydraulics for gearbox removal
A few conditions are attached to the removal or installation of a co-axial gearbox. It must be possible to be able to lower the gearbox, roughly in the middle, under the vehicle carefully. It can be dangerous if two people
try to do this manually. In this case, a hoist or a pit with suitable auxiliary hydraulics is recommended.
| Necessity for special tools
Results of battery disconnection
It must be also established whether or not one has the necessary tools. Nowadays, special screws, e.g., for the starter, are often used. The question of the economic efficiency also arises. A vital point is, what to do
with the battery during the operation. Can it be disconnected, and what are the results? Must perhaps only the radio be re-coded afterwards, or are there control devices which also no longer work? Is one prepared for
the results? It is hardly conceivable that one can simply strip the insulation from the very thick plus cable.
It is also important that one protects the car interior against soiling. It may be necessary, e.g., when dismantling the gear-change unit, to work on the central console. In this case, the covering of the seats and the leg
room would be wise. Because nowadays, virtually no screws are tightened without a torque wrench, their numerical values should be established beforehand.
|Disassembling the drive shaft
We assume, at this point, that the proper disconnection work has been done. Also that the vehicle is well secured in the working height. Then, first of all, our attention is drawn to the drive shaft and its removability.
Perhaps it is possible to loosen it from the gearbox and allow it too swing down. Otherwise it must be also unscrewed from the rear final drive.
|Marking helps when re-mounting
It makes sense to mark the parts before removing them from their position. Perhaps with paint or with a centre-punch. The reason for this is, that the drive shaft, e.g., must be mounted again in the same spline-
gearing position as it was before removal.
Now all the connections with the gearbox can be loosened. Not only the electrical system, but also the gear-change unit. This poses fewer problems with a linkage system, if one can unscrew it at suitable place
properly, or if it can be swung downwards from the ball joints. If Bowden-cables exist, even partly, their settings should, under no circumstances, be changed. Ideally, the gearbox is re-installed in precisely same place
as before, otherwise adjustment work is necessary.
|Deactivate the clutch operation
Since as a rule, the clutch housing is directly connected with the gearbox, the clutch hydraulics must be disassembled or the Bowden-cable removed. In the latter case, it can be
annoying if it is self-adjusting. If the slave cylinder is mounted within the clutch housing, only draining off of the brake fluid of the clutch hydraulics helps, which means re-filling and bleeding when reassembling.
|Mount the additional holding fixture, carefully remove the gearbox
Actually, now the way is free for the dismantling of the mounting, normally at the rear of the gearbox. It must then be supported against dropping out and all the screws around the clutch housing can be loosened.
During this operation caution is to be taken if the starter occasionally falls out. Then, with a crowbar, not using too much force, the gearbox should be able to be pulled out to the rear, and to be lowered. Of course, it
must be ensured that no other parts, which could hinder the action, are in the way.
|Difficulties after a clutch repair
The installation occurs in the reverse order. There can be difficulties, if at the same time, the clutch was replaced. Then the gearbox cannot as easily be pushed forward into the gearing of the clutch disc. By no means
should force be used. The complete consolidation into the clutch housing is, in the motor car gearbox, basically done with muscle power. If this does not work, one must stop and check once again that the gearbox
shaft has a free path into the clutch.
|For manual gearboxes only
This description is not complete for a fully automatic gearbox. During the dismantling, extreme care is to be taken against excessive oil flow if one simply loosens the screws in the clutch housing and the gearbox is
pulled to the rear. It is better, in this case, to remove the torque converter from the word go. 06/09