I replaced my camshaft seal and realized that it was leaking again. I replaced it again thinking that it was a bad seal. I didn't notice any grooves or Nick's on the shaft. If I use a repair sleeve do I need to remove the flange after it is installed or can I leave it on. I cannot see how I can remove it later. Is it possible to install the sleeve while the cam is in the engine or does it need to be removed. Last question is their a double lipped or a different seal that can be used. This was an international seal.