We check the oil level on a cooled gearbox.
Using a rag, clean the gearbox housing around the filler hole.

Using a 17 mm spanner, unscrew the filler plug in the gearbox housing (the front propeller shaft has been removed for clarity).
If there is a normal amount of oil in the gearbox, its level should reach the bottom edge of the filler hole - check with your finger. If the oil level is significantly below the required level...

using a transmission oil syringe, add oil to the lower edge of the filler hole (oil will start to flow out of the hole).
When the excess oil has drained, remove the oil drips with a rag. We screw on the cork.
