Rob, On engines with balance gears,the vertical tube is to add oil only,the side dipstick is the level check. The vertical tube has a short stick,because a long dipstick will hit the balance gears. My 147 with original engine and balance gears is set up that way (the gears went in the trash when I o'hauled it). My 126 (K301)has a factory replacement engine (black engine)also had balance gears (now in the trash can) and a different style side dipstick and no vertical dipstick tube. On it the side dipstick tube is larger in diameter than the 147 and is both a level ck and to add oil. After all these years non factory combinations have been created.