Saville
Well Known Member
Hi all,
I'm trying to understand the Lycoming engine designations as well as obtain their dimensions. I'm on the Lycoming page. Part of the nomenclature I understand; part I do not.
So you have:
Prefix-displacement Configuration
Prefixes are well defined on the Lycoming page: O, IO, AE etc. so I understand those.
Displacement - no problem.
Configuration?
I don't see any clear definition of those but have been able to figure some out (I think).
A1A for example.
From what I can tell, the "1" means that the engine is rigged for C/S prop. A "2" generally seems to mean not rigged for C/S prop.
Is that correct?
However it doesn't seem to be the case that the letters on either side of the number means anything. You have to look at the descriptions like:
"Same as A3A except for straight riser in oil sump and -32 carburettor "
to know how that model is configured. Is that also correct?
Lastly, how does one find out if one particulare engine can be placed on the same mount as another? The configuration descriptions will tell you things like:
O-320-A2D - Same as E3D but with conical mounts.
But how does one find out if an O-360 rigged for conical mounts can be bolted to yoru engine mount where an O-320-A2D was previously hung?
the A2D doesn't sem to mean the same things across different engines. For example:
O-320-A2D - Same as E3D but with conical mounts.
O-360-A2D - Same as the A1D except that it has no provisions for a controllable pitch propeller.
O-320-B2D - Same as D1D but with conical engine mounts ...
Can I replace the O-320-A2D with a O-320-B2D?
Is there any place I can get a listing of the dimensions of the mounting points of the engines so that I can determine if a mount for one engine works with another?
Thanks
I'm trying to understand the Lycoming engine designations as well as obtain their dimensions. I'm on the Lycoming page. Part of the nomenclature I understand; part I do not.
So you have:
Prefix-displacement Configuration
Prefixes are well defined on the Lycoming page: O, IO, AE etc. so I understand those.
Displacement - no problem.
Configuration?
I don't see any clear definition of those but have been able to figure some out (I think).
A1A for example.
From what I can tell, the "1" means that the engine is rigged for C/S prop. A "2" generally seems to mean not rigged for C/S prop.
Is that correct?
However it doesn't seem to be the case that the letters on either side of the number means anything. You have to look at the descriptions like:
"Same as A3A except for straight riser in oil sump and -32 carburettor "
to know how that model is configured. Is that also correct?
Lastly, how does one find out if one particulare engine can be placed on the same mount as another? The configuration descriptions will tell you things like:
O-320-A2D - Same as E3D but with conical mounts.
But how does one find out if an O-360 rigged for conical mounts can be bolted to yoru engine mount where an O-320-A2D was previously hung?
the A2D doesn't sem to mean the same things across different engines. For example:
O-320-A2D - Same as E3D but with conical mounts.
O-360-A2D - Same as the A1D except that it has no provisions for a controllable pitch propeller.
O-320-B2D - Same as D1D but with conical engine mounts ...
Can I replace the O-320-A2D with a O-320-B2D?
Is there any place I can get a listing of the dimensions of the mounting points of the engines so that I can determine if a mount for one engine works with another?
Thanks
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