With some of these dipstick designs, there is a quirk that you have to get used to in that they will read low right after the engine is shut down, then if you pull the stick out and allow the level in the dipstick tube to equalize, it reads correctly. With a cold engine sometimes the opposite happens, the level will rise up above full, but again if you pull the stick out and wait a few minutes, the level will equalize. I think its because with a hot engine, warm air in the tube prevents the oil level from rising as the oil drains back to the pan, then when you pull the stick out the pressure equalizes and the oil rises to its proper level. When the engine is cold the opposite happens, warm air in the tube contracts and pulls oil up the tube so it reads high. Either way you pull the stick and wait a few minutes for a true reading. This is all because unlike an automotive application on some inboard engines the dipstick does not pass through the block to the oil pan, it is in a tube that connects to the normal oil drain. So in order for the oil to read correctly it must be able to reach the correct level in the tube.
