This might be a foolish question, but I can't seem to figure out what type of fluid is supposed to go in the small container on the front bottom right of my engine. I have looked at the owners manual and the illustrations I am finding don't label it whatsoever. It is running low on the fluid in it and I can't seem to tell what it is. The tank I am speaking of is the one with the red cap in the photo I attached. Thanks in advance!