some saws have a breather hole in the oil tank, this is covered by a piece of sponge to keep out debris.
malce
January 2009
All tanks need a breather, otherwise by definition a vacuum wouldn't let the oil out eventually. There is a small breather hole in the side of the crankcase when you remove the chain brake cover.pleasant
pleasant
January 2009
most saws don't have them they work by vacuum, so check the pump and make sure that its clean were the oil comes out...! so take the chain off and clean the saw.
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