johnhibbs
New Member
A lot of people know about Seafoam for treating the engine but have you heard about STIHL engine de-carbonizer (EDTA is the main chemical ingredient)? When I was putting a new head gasket on my M2 I tried some Seafoam to see if it would disolve the carbon on the piston heads. It didn't do anything to the carbon. I guess I'm not convinced Seafoam does all that much but a lot of people swear by it.
Recently I pulled the spark plugs and spayed some EDTA into the cylinders and let it stand for a couple of weeks. I rotated the flywheel several times by hand to get it spread around. At the same time I soaked the spark plugs in some of the stuff to see what it would do. I placed them in a zip lock bag with the stuff.
When I checked back a week later all of the carbon was gone from the spark plugs. The clear EDTA liquid had turned a reddish color. When I rotated the flywheel the same reddish color liquid came out of the spark plug sockets. I can't say for sure but I would guess that the inside of my engine is free of carbon.
Since I don't have anything better to do I did it twice. The first time a ton of smoke poured out of the exhaust. I decided why not do it again since the first time it seemed to do something. The second time I waited about 2 weeks for the stuff to do its thing.
This time when I rotated to flywheel to get the stuff out before installing the plugs back I didn't notice any red liquid. Maybe once is enough. Something interesting though. No smoke. Usually when I run the boat on the hose I get smoke. Even after when I turn the boat off smoke usually comes out the back for a while. This time nothing. No smoke. Maybe the engine is like new and zero carbon.
I need to run it on the hose a few more time before I'm convince the smoke is gone.
Recently I pulled the spark plugs and spayed some EDTA into the cylinders and let it stand for a couple of weeks. I rotated the flywheel several times by hand to get it spread around. At the same time I soaked the spark plugs in some of the stuff to see what it would do. I placed them in a zip lock bag with the stuff.
When I checked back a week later all of the carbon was gone from the spark plugs. The clear EDTA liquid had turned a reddish color. When I rotated the flywheel the same reddish color liquid came out of the spark plug sockets. I can't say for sure but I would guess that the inside of my engine is free of carbon.
Since I don't have anything better to do I did it twice. The first time a ton of smoke poured out of the exhaust. I decided why not do it again since the first time it seemed to do something. The second time I waited about 2 weeks for the stuff to do its thing.
This time when I rotated to flywheel to get the stuff out before installing the plugs back I didn't notice any red liquid. Maybe once is enough. Something interesting though. No smoke. Usually when I run the boat on the hose I get smoke. Even after when I turn the boat off smoke usually comes out the back for a while. This time nothing. No smoke. Maybe the engine is like new and zero carbon.
I need to run it on the hose a few more time before I'm convince the smoke is gone.
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