Re: Coolant level?
Sorry. it is a penta aq125. I do not have a manual and do not see any marks. There is just a screen cup that protrudes a couple inches down under the cap.
The manual will explain it very good. You can also find the service manuals for the AQ125 (A&B) engines online with a bit of searching.
Based on the description it sounds like you are looking at the raw water screen. Note that the AQ125 engines have a separate cooling loop with the antifreeze in it. This will be put in the red expansion tank just to the right of the raw water basket.
When you take off the radiator cap you will see a little tab on the left side of the opening a few inches down. This is the "full" mark for the antifreeze.
The basket you are referring to is where the raw or sea water enters the heat exchanger to cool to the antifreeze. The screen is there to filter out any small gravel or debris that may be sucked in from the out drive.
It will be empty when the engine is not running in the water. When it does run in the water it will suck in large amounts of water. If you take the lid off while running you will have a lot of water shooting out everywhere.
You should check the basket for debris before every outing.
