Reply To: SW280 – Cooling water system – lube oil in the ht-water Home › Forums › SW280 › SW280 – Cooling water system – lube oil in the ht-water › Reply To: SW280 – Cooling water system – lube oil in the ht-water 15/09/2016 at 12:44 #212 Keymaster Hello, I would be more inclined to go with a leaking oil cooler as a source of contaminated water. The water pump should not allow mixing of liquids across the oil seal if the tell-tale hole is not blocked, an unusual combination. Best regards,