On 24 May 2021, at 9:21 am, Steven W. Boese SBoese@uwyo.edu <flyrotary@lancaironline.net> wrote:

I enlarged the drain and installed a vent to try to address both heat generation and internal pressurization.  This greatly reduced the internal pressure but no measurable decrease in heat generation was observed.

Steve Boese

On May 23, 2021, at 6:24 PM, Stephen Izett stephen.izett@gmail.com <flyrotary@lancaironline.net> wrote:

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Hi Matt 

I wouldn’t imagine pressure is a contributing factor, however the quantity of oil and churning losses generates heat.

I found this study - "Experimental Investigations on Churning Power Losses Generated in a Planetary Gear Set" https://www.researchgate.net/publication/321990749_Experimental_Investigations_on_Churning_Power_Losses_Generated_in_a_Planetary_Gear_Set

This study references the following further studies below:

Is there SIGNIFICANT power loss or heat generation that can be easily rectified by enlarging the drain and adding a breather?

Could someone read summarise and present a conclusion 😀

I’m guessing Steve B has already done this work.

Steve, were you interested in losses and heat generation, or seal problems associated with pressurisation, or both?

Cheers

Steve Izett

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