Thread: Provent oil drain back into TD5 turbo oil drain - one way valve required?

Documentation doesn't mention it , the information has been found from observation, not only on my vehicles , but have also seen numerous forum posts with people ask what is this water stuff.

For anyone interested, Western Filters sell a one way valve suitable for use with the Provent in the correct 1/2” size for $22.00 delivered. Non-Return Valve (2400843621) for MANN ProVent 200 Catch Can Pro Vent | eBay