I am in need of help with someone familiar with the Kawasaki FD620D 20HP liquid-cooled engine. When mowing last week I noticed oil coming out from the left side panel of my 1996 425 AWS. I removed the left panel and noted that the rubber plug on the oil fill tube had blown off. I was told it probably was a faulty engine breather. The engine runs beautiful without any exhaust smoke. I made a test with the engine running and the dipstick removed and there was more blow by at the dipstick tube than the rubber tube coming from the engine up to the air cleaner. I have looked at the engine parts prints at the John Deere parts site and cannot find any engine breather or its location. Will I have to remove the engine and tear it down to replace this breather part? If so does anyone know the part number. If I have to remove the engine I might as well rebuild the engine at the same time. What would be the approximate cost for new ring, valves, and a gasket set? Thank you in advance.