[quote pid=1090 author=Alexiskayak_7 date=1209318725]I'll spray PTFE while the engine is working or turned of?[/quote]
When its running is best to ensure plenty of lube gets deep into the charger scoll, spray both in the front and back chambers to give more even coverage. It pays to hold the rev's above tick over to avoid the fumes from aerosol causing engine stall(it not serious if it happens, just start it again!!)
Though if your still running the crankcase oil breather setup then there is a good chance the oil vapours/contaminants will wash off the PTFE lube more quickly, in which case I recommend the OEM Kluber grease, but it requires splitting scroll from cases to get good application.