Bob Kelly
Well-Known Member
Something i have noticed in the last month or so is that most Rotex Gear Reduction Boxes are in my thinking ... UPSIDE DOWN !
when the Manifacture planely states that the Gear Reduction box can be mounted eather way... if you are trying to get the center of gravity down simply turn the Gear box 180 degrees and lower the entire engine and prop that 3" it will give you.... or in the case of my Gyro I lowered the entire engine and prop 6" by doing that ...
ofcorse you'll change the drain plug and filler plugs ( swap them ) and use the other Oil outlet hole to check the gear oil ...
But it baffels me as to why i havn't seen more gear boxes turned arround !???? I havn't had any truble with mine sense i changed it 180 degrees
but i havn't gone on a 1hr flight eather ! ....
Don't get me wrong, i'm not calling everyone with a gearbox positioned the way rotex originally installed it a Dummie, but there has to be a reason for it ! , more than likely they simply don't know you can turn it arround !
... besides lowering your center of gravity , it will raise your thrustline
.... what i did was initionally raise my thrustline , then lowered it back to where it was by lowering the entire engine .
So in effect what i have done is lower the center of mass but keep the thrust line in the same place
This condition is preferable to what it was and will help prevent Power Push Overs.
Can any of you gents shed some light on this for me ? has what i've done indangered my gearbox ? despite what the manifacrures say ? ...( no i don't trust everything i read eather ! hehehe )
THanks for your help !
Bob......
when the Manifacture planely states that the Gear Reduction box can be mounted eather way... if you are trying to get the center of gravity down simply turn the Gear box 180 degrees and lower the entire engine and prop that 3" it will give you.... or in the case of my Gyro I lowered the entire engine and prop 6" by doing that ...
ofcorse you'll change the drain plug and filler plugs ( swap them ) and use the other Oil outlet hole to check the gear oil ...
But it baffels me as to why i havn't seen more gear boxes turned arround !???? I havn't had any truble with mine sense i changed it 180 degrees
but i havn't gone on a 1hr flight eather ! ....
Don't get me wrong, i'm not calling everyone with a gearbox positioned the way rotex originally installed it a Dummie, but there has to be a reason for it ! , more than likely they simply don't know you can turn it arround !
... besides lowering your center of gravity , it will raise your thrustline
.... what i did was initionally raise my thrustline , then lowered it back to where it was by lowering the entire engine .
So in effect what i have done is lower the center of mass but keep the thrust line in the same place
This condition is preferable to what it was and will help prevent Power Push Overs.
Can any of you gents shed some light on this for me ? has what i've done indangered my gearbox ? despite what the manifacrures say ? ...( no i don't trust everything i read eather ! hehehe )
THanks for your help !
Bob......
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