Kawasaki FR730V leaking oil at engine housing.

[asker123]

Hi there,
FR730V is on cub cadet zero turn SX54 inch mower.
it appears that the fitting at the engine housing is leaking oil.
can there be an O ring issue. how do I know the size?
Also, can I drain oil and change the O ring and put the drained oil back? or I need to change the oil? right now , the oil is new but if I mow, oil will get used. never drained the used oil and put back same oil hence asking.

 

[spasm3]

https://www.jackssmallengines.com/jacks-parts-lookup/manufacturer/kawasaki/4-stroke-engine/fr730v/fr730v-bs09-4-stroke-engine-fr730v/lubrication-equipment

 

[Cujet]

You can, of course, re-use the oil. The difficulty is in keeping it perfectly clean. Any dirt will ruin the oil and possibly the engine. Clearly, one can be as careful as possible, and still fail here.

I've used paint strainers (for automotive paint) to strain oil that I'm going to re-use.