I have been forced to admit that for racing one has to have a fixed pitch prop to win against competition with high performance fixed pitch props. Since I like to win I am forced to look into converting my O-360-A1A to fixed pitch prop operation and buy a high performance fixed pitch prop. With 6 more races to go in the season and being in 1st place by only 10 points the pressure to change is extreme. So I look at my full set of Lycoming Service Letter, Service Bulletins and Service Instructions and end up at SI no. 1435. I will not go into the details but the superficial treatment will assure inconsistent implementation across the fleet.
I researched the subject in this forum, I searched for part numbers in the Lycoming parts manual, I called the Lycoming Product Support line and I have consulted with friends and at this point I have to conclude that there is no single right way to make the complete conversion.
What I thought my attention would be focussed on was the inner crankshaft plug. Pierce or remove the rear crankshaft plug, install the front crankshaft plug is unambiguous but after that things get fuzzy. The word "should" is used with respect to removing the "propeller governor, adapter, oil line and fittings." Is that an all or nothing situation or can one pick and choose the implementation. Obviously in my immediate situation it would be easiest to remove the oil line and fittings, plug the ports and not deal with the inaccessible governor right now but I' was told I must remove the governor when I called the factory. I am also told that I can put a 72378 cover on the adapter or I can remove the adapter and shaftgear and install a different cover directly on the accessory case (remember SI 1435 said you "should" remove the adapter). I have to call a part specialist to get the hardware part numbers for that implementation method.
I attempted to get the port filling plugs identified but I'm not sure I have them yet. The best information I have is an AN814-6L with an MS29512-6 O-ring for the rear port and a Lycoming STD-700 for the front.
For the rear plug in the crankshaft I was told to make a very sharp punch by grinding a store bought tool. The steel is a soft steel and it will deform. If it deforms instead of piercing it can be removed entirely around the offset oil tube in the crankshaft. Either pierced or removed works - I like removed but will take what I get without damaging the oil tube in the crankshaft.
For installing the front Crankshaft plug I am told I can rent a 64681 tool from a Lycoming distributor or use a socket and a "dead blow hammer" to install it.I was advised to apply a Pematex sealing compound to the edge of the plug before installing it.(I believe it was #2 but I'm not absolutely sure of that).
I will work through this but it is not a simple clearly defined process without risk.
Bob Axsom
I researched the subject in this forum, I searched for part numbers in the Lycoming parts manual, I called the Lycoming Product Support line and I have consulted with friends and at this point I have to conclude that there is no single right way to make the complete conversion.
What I thought my attention would be focussed on was the inner crankshaft plug. Pierce or remove the rear crankshaft plug, install the front crankshaft plug is unambiguous but after that things get fuzzy. The word "should" is used with respect to removing the "propeller governor, adapter, oil line and fittings." Is that an all or nothing situation or can one pick and choose the implementation. Obviously in my immediate situation it would be easiest to remove the oil line and fittings, plug the ports and not deal with the inaccessible governor right now but I' was told I must remove the governor when I called the factory. I am also told that I can put a 72378 cover on the adapter or I can remove the adapter and shaftgear and install a different cover directly on the accessory case (remember SI 1435 said you "should" remove the adapter). I have to call a part specialist to get the hardware part numbers for that implementation method.
I attempted to get the port filling plugs identified but I'm not sure I have them yet. The best information I have is an AN814-6L with an MS29512-6 O-ring for the rear port and a Lycoming STD-700 for the front.
For the rear plug in the crankshaft I was told to make a very sharp punch by grinding a store bought tool. The steel is a soft steel and it will deform. If it deforms instead of piercing it can be removed entirely around the offset oil tube in the crankshaft. Either pierced or removed works - I like removed but will take what I get without damaging the oil tube in the crankshaft.
For installing the front Crankshaft plug I am told I can rent a 64681 tool from a Lycoming distributor or use a socket and a "dead blow hammer" to install it.I was advised to apply a Pematex sealing compound to the edge of the plug before installing it.(I believe it was #2 but I'm not absolutely sure of that).
I will work through this but it is not a simple clearly defined process without risk.
Bob Axsom
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