Merc Clean #2

[cmpky]

I started using merc clean #2 in my 200 efi 3.0 litre. I have recently noticed a good amount of sticky carbon residue around the outside of the propeler. Is this normal? I have always used marine stabil in every tank and regular merc clean but they started making the different levels of mercury treatments. I started using this about a month ago and since then I started seeing the residue. Maybe this is a sign that it is working?

[EuropeanAM]

I believe you're referring to "#2 QuickCleen", correct?

You may initially notice more residue around the prop, as carbon and various hydrocarbon deposits begin to disolve, and are deposited as they exit the propeller.

Any time there is a question on exhaust residue, it's a good idea to take a quick read of the spark plugs, just to ensure that there's not an under-lying rich running condition (perhaps causing additional exhaust carbon).