The oil/grease is so thick and the openings in the lower portion of the outboard motor are narrow there is a potential for large air pockets to form, causing the motor to have less oil/grease than it should have. By adding from the bottom up you will see a more accurate fill with less air pockets.
You can top off the oil in the gearbox on a 206 Zest by removing the fill plug on the top of the gearbox and using a funnel to fill with oil.
on the front of the gear box there is a plastic wing nut undo this and fill to the bottom of the hole
it's gotta be there. towards the bottom. keep looking. maybe lay underneath it and look up. gotta be there.
there is a gearbox in the middle of the rear axle with a drain nut on the bottom and a fill nut on the top
you fill up the manual gearbox on the top through the beather nut , it has a white plastic cap on the top and use the correct oil
You unscrew the top plug on the lower unit and carefully unscrew the drain plug on the bottom and quickly put the nozzle end of the oil container in it and keep squeezing till the oil just starts to come out of the top hole. This runs any water and/or air out and guarantees that the gearbox is lubed properly.
You fill it through the dipstick hole.
The top two holes are a fill level, and a vent hole. Remove both of these plugs when filling the gearcase to ensure proper oil level, and ease of filling.
Always fill the gearcase from the bottom drain hole until oil flows out the top vent hole. In this way, you can ensure that all the air has been expelled from the gearcase, and that it is completely full.
The gearbox oil fill plug can be located, in your Peugeot 306 2.0, on the top of the gearbox nears the back. The plug can be removed with a three-quarter inch socket
Seem to be on top of transaxle in rear, very hard to see & get to?
There is a small plastic thumb screw wing nut on the side, not the top of box as that is a breather pipe. Use a pipe and fill until the oil starts dribbling out, the gearbox will hold around 3 litres on a Renault Kangoo on JC1 boxes.