Technical data

For all engine models, a propeller half-coupling, bored to shaft size for the specific order, is
supplied. The coupling either has a keyway with set screws or is of the clamping type.
The forward end of the propeller shaft has a long straight keyway. Any burrs should be removed
from the shaft end. The coupling "should be a light drive fit on the shaft and the shat should not have, to
be scraped down or filed in order to get a fit. It is important that the key be properly fitted both to the
shaft and the coupling. The key should fit the side of the keyway very closely, but should not ,touch the
top of the keyway in the hub of the coupling.
If it seems difficult to drive the coupling over the shaft, the coupling can be expanded by heating
in a pail of boiling water. The face of the propeller coupling must be exactly perpendicular to the
centerline or axis of the propeller shaft.
PROPELLER
The type and size of propeller varies with the gear ratio and must be selected to fit the
application based upon boat tests. To utilize the full power of the engine, and to achieve ideal loading
conditions, it is desirable to use a propeller which will permit the engine to reach its full rated speed at
full throttle under normal load.
ALIGNMENT OF ENGINE
The engine must be properly and exactly aligned with the propeller shaft. No matter what
material is used to build a boat it will be found to be flexible to some extent and the boat hull will change
its serape to a greater extent than is usually realized when it is launched and operated in the water. It is
therefore very important to check the engine alignment at frequent intervals and to correct any errors
when they may appear.
Misalignment between the engine and the propeller shaft is the cause of troubles which are
blamed often on other causes. It will create excessive bearing wear, rapid shaft wear and will, in many
cases, reduce the life of the hull by loosening the hull fastenings. A bent propeller shaft will have exactly
the same effect and it is therefore necessary that the propeller shaft'' itself be perfectly straight.
One particularly annoying result of misalignment may be leakage of transmission oil through the
rear oil seal. Check to make sure that alignment is within the limits prescribed.
The engine should be moved around on the bed and supported on the screw-jacks or shims until
the two halves of the couplings can be brought together without using force and so that the flanges meet
evenly all around. It is best not to drill the foundation for the foundation bolts until the approximate
alignment has been accurately determined.
Never attempt a final alignment with the boat on land. The boat should be in the water and have
had an opportunity to assume its final water form. It is best to do the alignment with the fuel and water
tanks about half full and all the usual equipment on board and after the main mast has been stepped and
final rigging has been accomplished.
Take plenty of time in making this alignment and do not be satisfied with anything less than
perfect results.