D
Dick Dixon
For all the Yanmar diesel folks.....I have a 1993 30 HP three-cylinder raw water cooled diesel. The engine has approximately 1800 hours. Over the past few months her power has diminished while under load from 2800 down to no more 2400 RPM. Along with a obvious loss of power, she produced some white/grey smoke at normal RPM but when a real load was required black smoke would exit and the engine would bog down. I pulled the injectors and had them tested....they were found to be in great shape...a cleaning was performed however. When I removed No. 1 cyclinder's injector, I found the O-ring to be in bad shape with apparent "blow by" occurring. I replaced the O-ring. There is no smoking now. I also changed both fuel filters (which is done annually anyway)and bled the system. All three cylinders are firing; the engine runs exceptionally well when no load is present, easily reaching 2800-2900 RPM's with no problem. But once load is engaged she will not climb beyond 2400 RPM's. Also, no coolent is escaping into the engine. Additionally, the raw water impeller has been changed recently. The propeller is clean and there appears to be no mechanical prolem in the shafting. The breather is clean and clear.
Today I plan to pull the mixing elbow and perform cleaning maintenance. Since I've only owned the boat for 4-1/2 years, I'm unsure of its age.
If it isn't the mixing elbow, does anyone have an idea as to what may be happening?
Thanks,
Dick
Today I plan to pull the mixing elbow and perform cleaning maintenance. Since I've only owned the boat for 4-1/2 years, I'm unsure of its age.
If it isn't the mixing elbow, does anyone have an idea as to what may be happening?
Thanks,
Dick