Gen 1 lower shaft queston.

[Condor1970]

I notice on the design of the Gen 1 vertical drive shaft for the water pump, there is only one roller bearing beneath the pump which prevents upward movement. That means the in essence the pinion gear basically rests on top of the main drive gear on the lower propeller shaft... correct?

To do this, means there will be some vertical play in the shaft, especially noticed when the lower unti is removed for pump maintenance. That vertical movement will occur until it seats the roller bearing on that shaft. I assume this will occur by itself when the unit is in gear, as the rotation of those gears will push the shaft upward into the bearing cup.

My question is, when the unit is disassembled for maintenance like this, how much vertical movement should I expect when I gently pull up on the shaft?

 

[achris]

Can be anything up to about 3/16"... And the shafts are always spinning, even when in neutral. The gear selection is done on the prop shaft, so all the gears are always spinning whenever the engine is running. From the description you have an Alpha One or MR drive. The earlier drives (MC-1 and R) have that top bearing facing the other way and a 'pre-load' pin in the top of the lower drive shaft. As the pinion and forward and reverse geasr tend to push away from each other under load, the pre-load pin pushes the shaft down and holds the gears in correct mesh....

Chris.......