Decarbonizing a motor?

[Striperjoe]

I have a 2001 HPDI 200hp and have 700 hours on the tach. I have used faithfully ring free constant treat 1oz per 10 gallons and also only used Yamalube 2 stroke oil through this engine and I'm orginal owner. Does this motor need to have a more agressive decarboning at every 100 hours or will the ring free do the trick? And one more question can you use a Napa product called SEA Foam and get the same results in the end? If I need to do a more agressive cleaning how do you reccommend using one of these products? Maybe all these chemicals are hog wash?
I have always had a authorized Yamaha dealer tune up my boat once a year and he has never said anything about decarboning. Is this just a way to get more repair business or sell more motors? All comments would be helpfull
thanks Striperjoe

 

[gearyg]

Re: Decarbonizing a motor?

Decarbonizing and motor will not hurt it. I used to have an old Johnson carbed and every year when I decarbed it, there would be a big black cloud of smoke (the first year it stuck to my neighbors garage door). Now I have a Yamaha 4-stroke and when I decarb it, it seems that nothing is there...ever. These newer motors are pretty efficient and clean, especially if you run ring free peridocally.

If you want to decarb, use Seafoam (my opinion). Remove each spark plug and spray directly into each cylinder (for about 5-8 seconds). work it in by turning the engine just so the pistons move a couple of times. Then respray for about 3-5 seconds. Replace plugs (might as well gap them also, the Seafoam will automatically clean the plugs) and let it sit for about 1/2 day or so. Then run for about 5min-10min. Do an oil change (your oil may get contaminated) and you are done. Really simple and can only help and engine