woko said..
IMHO doing those sort of things to a little old motor could prematurely expose normal wear issues. does it burn oil ?
is it easy to start ?
does it blow smoke ? if it don't itch don't scratch it
change the oil with the recommendation oil
change the oil filter and most important change the fuel filters regularly, and there should be but with marine engines not all ways so an air filter, if you got one clean it
Decarbonised with a recommended green liquid. Changed oil ( added 4ml of diesel in oil just before oil change to clean the engine inside). Added a special foam inside the air intake. Now engine in very quiet, still 80% of throttle and 6 knots is there. Over 80% of throttle engine is only smoking more. I feel that propeller is slightly overlitched. But one new thing came up, now when I am trying to push throttle more than 80% the throttle is slowly coming back to that 80%. Very strange but actually excellent because if I accidentally push it to much I will come back where should be. Otherwise engine is smoking black but doesn't go faster. Probably 1 side less in pitch would allow the engine to rev more but I am happy to reach full hull speed with 80% of throttle.
Finally, after all this hassle (changing prop, decarbobnseing, cleaning the air intake) I can cruise quietly with my family around the harbour at 6 to 7 knots of speed.
That expensive green staff really works. Engine is so quiet and on 80% of throttle doesn't smoke at all. Now is very easy to reach hull speed. It makes a big difference to cruise 6 to 7 knots (depends on tigh) and 3 knots (broken propeller ..)
Very very pleased with results, thank you guys very much for your help and suggestions.
I got my offshore gear and I am out soon. Now when i have reliable engine and prop I can sail outside of heads and when weather turns ugly I can put the engine on and run home.
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