decarbing 4strokes

[hawilson2]

Used to own a 2stroke C115 Yamaha that was carburetored. Used seafoam to decarb annually and ran 1 oz of ring free with every 6-8 gal of gas on a regular basis. Now I own a 2006 F115 Yamaha. Fuel injected so won't be spraying any carbs. I was told that with 4strokes carbon build up is not as pronounced as with 2strokes and is not really an issue. My questions are:

Is regular decarb recommended for 4strokes? How often? And how, with fuel injection?
Is adding ring free to the gas still recommended and at what proportions?

Thanks in advance.

 

[rodbolt]

Re: decarbing 4strokes

basically two ways, on is to attempt spraying it down the ISC intake hose.
the other easiest is to hook up a remote 6 gallon tank,mix ring free at 2-1.5 OZ per gallon and run a 6 galon mix through it.
its reccomended every 200 hours or once per year.
standard use is 1 OZ per 10 gallons.

 

[hawilson2]

Re: decarbing 4strokes

Thanks for the response. The ISC route sounds complicated. Reading the ring free bottle it says the minumum shock treatment per engine is 3.3l - 1.7l engine - 64 gallons; 1.6l-700cc engine - 24 gallons; 699cc - and below - 12 gallons with 2 ozs/gallon. My owners manual says the F115 is a 1741 cc engine (displacement, I assume). Converted that's 1.7L. So for shocking I should run between 24 and 64 gallons through?
A lot more than the 6 you mentioned. I may not be doing the math correctly not being a metric person.

So I run some amount of treated gas through and then change the oil and plugs? It may take me a while to run 24-64 gallons through. Am I figuring this correctly?

 

[yamamarinetech40]

Re: decarbing 4strokes

Just do exactly what rodbolt told you, and I promise it'll work.

 

[hawilson2]

Re: decarbing 4strokes

Thanks. I would much rather do 6 gallons. Should I change the oil and plugs after running the 6 gallons through for shock treatment?

 

[pine island fred]

Re: decarbing 4strokes

Had a lot of 4 strokes in my life starting out with a 49 CHEVY. Why are you concerned with decarbonising a YAMAHA? Is there something special, out of the ordinary with that engine that I am not aware of?
Am the proud owner of a real morphodite. 6 cyl. SUZUKI, 4 valves per cyl., in line! Takes 7 1/2 qts. of oil with a filter change. Lots of oil to dump so I take it to the MOBIL station quick lube for an oil change. Well, after 23K miles, ( did have the oil changed every 6K at the dealer before they went out of business) I should have them run an oil flush additive before they dump the oil. Then a fuel system/ injector cleaner treatment. Some other treatment that I forget plus changing the tire air to nitrogen. So much snake oil all over that place, wont be back, will get a larger drain pan and do it myself.
I do run sea foam or yamaha ring free in my MERC 2 stroke. 1 oz. per gallon of sea foam, 1 oz. per 10 gallons of ring free. I change the oil/filter reguarly in my F-115 but no other additives. Its a 4 stroke engine just like any other, thats why I bought it. regards FRED

 

[rodbolt]

Re: decarbing 4strokes

actually we are finding decarbing the 4 strokes actully helps.
do a leak down test before and after decarbing and normally you will see an improvement in numbers.
outboard 4 strokes run in a vastly different operating condition than automobiles.
Nitrogen in the tires? Freds done gone airborne on us .
actually I was chatting with Ricky Clough of Clough ford last week when I dropped the trucks off for service and he mentioned that quite a number of new vehicles are reccomending nitrogen in the tires.
how stupid can the auto/truck manufactures get?
is it a wonder they are failing??
so now it will cost about 20 dollars to check/adjust the nitrogen pressures in your tires.
along with the 4 dollar a gallon E10 crap fuel we get.
in this state to handle compressed gas you must have the pressure vessel inspected,compressed air tanks included, and the inspection posted on the board with the current MSDS,workmans comp,unemployment,minimum wage sheets and all the other crap no one but the inspector writing the citation actually reads on the bulliten board.
with compressed nitrogen he will have to not only buy the setup with regulators but post yet another MSDS,send a tech for training on handling nitrogen but actually buy the stuff.
its amazing how long compressed air actually worked and the whole time we just did not know it.
enough rant, when your ready to do an oil change decarb it using the method of your choice then do your oil change/tuneup.