Is it a problem to let shaft turn with Hydraulic Gearbox?

[swanny]

I have a new PRM150 gearbox with no shaft brake as the feathering Kiwi Propeller should not turn the shaft. However, it often does turn it a little. I can easily stop it with my hand but turn it does, albeit slowly at about 50rpm. Is this a problem for the gearbox???

 

[PCUK]

It should tell you in the manual. Some makes are OK some are not. You might need a shaft brake to be on the safe side.

 

[dansar]

Hi

All new PRM gearboxes have been designed to allow the free wheeling of the propellor and shaft without harming the transmission. Check your manual (page 8 in mine) or contact PRM if you're not sure.

dansar

 

[Piers]

The manuals on my Fleming's Twin Disc gearboxes state that windmilling is allowed, provided, I do not exceed normal propulsion speed of the vessel, run the engine with transmission in neutral at normal fluid pressures for 5 minutes, every 8 hours, and the oil level is at the full mark on the dipstick.

In other words, every gearbox manufacturer will state what's allowed. Stay within that and you should be fine.

 

[swanny]

Thanks guys - suitably reassured! ta

 

[markdj]

Working on a steel boat with a borg warner gearbox...

Where can I purchase a shaft break? Currently, the shaft has a large disc of steel on it with a bolt which is tied off but a shaft brake would be the solution.

Any help greatly appreciated.