Tips from Mahlon on leaking crankshaft seal

11 Nov 2018 Tips from Mahlon on leaking crankshaft seal

http://www.vansairforce.com/community/showthread.php?t=164655 

If you have a chronic nose seal weep that leaks between the seal and the shaft a good remedy is to helix the shaft per CM sb M74-6. Its not a Lycoming SB but the theory works well on any engine. The helixing actually makes a pump the moves the oil away from the seal lip. And a note…when you do it don’t be afraid to really use a lot of pressure on the abrasive. When you are done helixing, the shaft should look really, really scratched up. I know many will say that the shaft should be polished there, or the seal will wear out. But this works and it works well permanently, seal lip wear is not an issue. Done it on many, many Lycoming shafts with great success. Also, have had the best luck using the Lycoming service replacement seal, that is a split one and doesn’t have an installer installed seal spring. The leaf spring that supplies lip pressure is molded into the seal.
Good Luck,
Mahlon