Reversing Outboard output shaft rotation

[Andrew Leigh]

Just a left field question. I have a RIB with two 40hp 40XWL on, both rotating in the same direction. I was wanting to have them contra rotate.

Was watching a video this a.m. on the two gears in the lower unit and thought, surely one simply has to change the front spur gear with the rear spur gear, along with the clutch and the shaft will rotate in the opposite direction? Then I though no, surely it cannot be that simple?

 

[Faztbullet]

Highly doubt it do to gear design and bearings used

 

[boscoe99]

It is not that simple. On the other hand, it is not that complex.

In a Yamaha counter rotating gear case, the forward and reverse gear locations are reversed from the standard lower unit. The forward gear is
now in the back of the case, behind the pinion gear. Reverse gear is located in the front of the case.

It is not practical nor cost effective to try and convert a RH gear case to a LH gear case. It needs to be designed and constructed from the start to be either one or the other.

 

[racerone]

Agreed ----Bearings need to be beefed up to use the reverse ( opposite rotation ) gear with lefthand prop for forward motion !!