How to decarbon a 4 stroke

[TnTommy]

I’ve been looking into removing carbon deposits from my evinrude 50hp 4 stroke fuel injected, E50PL4SS, the manual says this should be done every 50hrs I bought the boat this summer and I doubt this has been done in the last 10years. The manual calls for Evinrude/Johnson engine tuner.The directions are to spray it in carbs or air intake, so with no carbs where would I spray it?

 

[racerone]

I would not worry about doing this.------Most 4 stroke engines in pickup trucks have not had this procedure done in 10 years ( 150,000 miles ) either.

 

[TnTommy]

Was also wondering if it was necessary?

 

[Crosbyman]

the 2005 version of an ETEC as a direct oil feed into the incoming fuel line for purpose of mixing in ..."some " X100 oil with Carbon gard.

you could always mix some in say 100/1 in your fuel supply or look at Evinrude products to mix in the fuel .

Some folks like SEAFOAM (see utubes) some folks don'T like it.

now the question... Having any problems ?

 

[airshot]

If it really concerns you, remove the plugs and spray in some SeaFoam, turn the engine over a few times with no ignition. Let sit for a few hours, if really bad do that a second time. Put plugs back in and fire it up. If there were lots of carbon buildup it will smoke like crazy, if not much carbon then lighter smoke. Being a four stroke, I would not expect much smoke, usually not much carbon buildup in them. If your engine is running well, why bother? Don't try fixing what isn't broke....