dip stick length

Need to know the length of the 225 dip stick. Got one because mine was missing and it dosn't read the oil level. Just changed the oil last week and added 2 more qts after putting in the dip stick and still no reading (she does burn some oil, but I dont think 2 qts in week). This dip stick that I got is 12 inches long ,from where it seats on the tube to the end. My motor is a 1972 225. Thanks in advance, Pete