I work with volvo penta engines. I would like to know if you have any kit to analyze the antifreeze (green). In the manual brand to analyze but I have no benchmarks. The engine that we use on board isthe C D16 to MG.
You can pick up a Specific gravity tester at any auto repair place (about $15). You suck up a little of the anti-freeze and it will tell you to what degree the engine is protected to. In the old days it had three or four balls that would float and tell you what temperature you are protected to, but now they usually have an arm that points to the degrees. This will let you know whether the mixture is correct, but will not tell you if the anti-freeze is dirty or has begun to break down.
You can do some of it by sight and see if the anti-freeze looks clean, doesn’t smell oddly and doesn’t have an oily feel to it.
The Coast Guard sometimes sends samples off to a lab to check, but most times it is not worth doing this unless you are trying to do some problem analysis.