Is Oil Purge Required?

Hi Brett

Check out the Rotax video on purging, it is really not that hard.  If you have done the full purge at first installation the only risk is introduction of air into the system on the suction side of the oil pump.  The oil pressure switch is on the charge or pressure side so not an issue.  Oil tank cleaning, as long as you do not drain the suction line, is really no different from a normal oil change.  

https://www.youtube.com/watch?v=UwARvpIP9-k

Cheers

The valve lifter procedure at the last part of purging looks like a PITA to do.  Is it really necessary anytime other than new engine or complete disassembly?

Hi Dave

If you have a new engine or one where you have changed the oil lines or oil cooler then checking for a soft lifer is required.  If you did it on your initial installation and all was good then logic says it is not required as long as you have not drained anything on the charge side of the oil pump,  (suction side, oil tank to oil pump) The oil return is not an issue at all, it is always full of air and that is what the oil tank design is for, it removes the air from the oil so a solid stream of oil is what is drawn into the engine.  If you pull heads off the engine or if you change the rubber hoses for the 5 year then do the compleat purge.  

Cheers