Vetus Bullflex Instructions D'installation page 4

Mounting
In connection with the axial movement of the propeller shaft a
minimum free space between outer bearing and propeller hub is
required.
Propeller-thrust
N.B. When sailing in forward direction the rubber part must be com-
pressed.
Using the Bullflex in combination with a V-drive type gearbox is not
allowed!
Over-size (larger) propeller shaft diameter
Reduce the propeller shaft
diameter for the taper length
(dimension 'A') to the given
dimension 'd' of the coupling,
see Overall dimensions.
Radius 'r' minimal 2 mm
(0.08").
Misalignment
The maximum allowable mis-
alignment of the propeller
shaft is 2˚.
4
030205.10
Centering ring
An engine on flexible mountings will, by definition, always bounce.
Where the propeller shaft is supported by one rigid bearing only, the
Bullflex coupling -with the centering ring installed- will function as a
flexible ball joint, see A.
When the propeller shaft is installed rigidly which means to say -sup-
ported by two (or more) non-flexible bearings- the propeller shaft
should not be affected by engine movements. Therefore remove the
centering ring in such an installation, see B.
If the length 'L' of the propeller shaft between the inner rigid bearing
and the flange of the gearbox is more than 20 times the propeller
shaft diameter 'd' , do not remove the centering ring.
A
B
Bullflex 1
Removal of centering ring:
Detach the bolts . Detach flange  from the hub and remove cen-
tering ring . Attach flange and reinstall the bolts (with a locking
agent, LOCTITE 222 Screwlock) and tighten with the specified torque
'T1' see table. Ensure that the holes in flange and rubber element are
in line during installation of the bolts. Deform the rubber element
with the assistance of a screw clamp.
Bullflex 2, 4, 8, 12, 16, 32
Bullflex
1 M8
2 M10
4 M12
8 M14 140 Nm
12 M16 220 Nm
16 M16 220 Nm
32 M20 430 Nm
Flexible propeller shaft coupling BULLFLEX
A
B
T1
25 Nm
50 Nm
90 Nm