Hi. New to Volvo Penta and this site but glad I found it
So I want to make sure I understand his correct.
Right hand rotation is better then left hand rotation for the outdrive?
Currently my prop rotates LH. I need to buy a new prop. I can easily change the rotation to RH if it will help prolong the life of my old drive.
Thanks for the help!!!!!
In addition to what Gary said, this can be a double edged sword, so to speak.
This is tuff to explain if you are not familiar with Volvo Penta's cone clutch transmission... so bear with me.
This is limited to the single prop drives:
All three transmission gears spin constantly when the engine is running.
The vertical shaft remains static until a gear is selected.
Once a gear direction selection has been made, the vertical shaft spins in the direction of that gear selected for forward propulsion.
LH prop requires this shaft to spin CW when viewed from above.
RH prop requires this shaft to spin CCW when viewed from above.
When spinning a LH prop, the power is transmitted via the transmission's
main drive gear and the
lower driven gear.
As said, this turns the vertical shaft in a CW direction when viewed from above.
When spinning a RH prop, the power is transmitted via the transmission's
main drive gear and the
upper driven gear.
This turns the vertical shaft in a CCW direction when viewed from above.
As per design, the gears sets themselves don't care which hand prop you run.
Here's the catch... actually several catches:
When we run a RH prop, the transmission's vertical shaft undergoes a downward force, which is countered by the special LH thread top nut.
When we run a LH prop, the transmission's vertical shaft undergoes a upward force, which is countered by the brass split ring keeper.
These brass split ring keepers undergo stress that will eventually cause them to expand and fail over time.
Gary is correct regarding the gear's bearing force.
The main drive gear and the selected driven gear want to oppose one another and cause a separation force.
When the upper driven is selected, the top cover controls the separation uplift force.
When the lower driven gear is selected, the Intermediate housing controls the separationg downward force.
In all my years witht the AQ series, I've never seen a top cover break due to this gear separation uplift force alone.
However, I have seen and repaired transmissions where the top cover has broken due to a split ring keeper failure that caused the vertical shaft to come up and through the top cover.
If your transmission has been turning a LH prop for years and years, you may want to look at this brass split ring keeper for signs of expansion.
If it is expanding, you had best replace it, especially with V-8 power!
The other catch:
A 280 drive trim fin/torque tab works well for either hand prop.
A 250, 270 or 275 trim fin/torque tab works best for a LH prop... and don't ask me why!
.