Hamilton Jet HJ212, Installation And Service Manual

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Design Basics
Installation and Service Manual
Figure 6: 'W' Configuration Driveshaft
1 Jet coupling flange 3 Jet mainshaft axis
2 Engine / gearbox flange
θ
1
and θ
2
must be equal
If X1 = X2 and both input and output axis meet at point P, then
θ
1
=
θ
The best method of alignment is to mount pointers on both jet coupling (or output) flange and engine (or
input) flange. The length of each pointer should be exactly the same and equal to half the nominal distance
between the two flanges.
Figure 7: 'Z' Configuration Driveshaft
1 Jet coupling flange 4 Engine /gearbox axis
2 Engine/coupling flange 'L' Axial distance between the universal driveshaft yokes
3 Jet mainshaft axis 'Q' Offset
θ
1
and θ
2
must be equal
Offset = L x Tan
θ
Jet Coupling Flange Details
Refer to drawing: HJ21202005 Close Coupling Kit.
Drivelines for Diesel Engines
A diesel engine installation will require the engine to be separately mounted from the jet with a torsionally
flexible coupling normally mounted at the engine flywheel. The coupling needs to be sufficiently flexible to
ensure that the slow speed torsional vibration resonance point occurs below engine idle RPM. This can only
be determined by carrying out a torsional vibration analysis on the complete driveline, engine, gearbox and
jet unit.
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