This question has been beating around a few forums with some debate for the last week. On the Moomba forum an Indmar engine technician from Indmar themselves posted this responce. Very good info especially if all you do is surf. The reponce:
"Running the boat heavily loaded at low RPM like you do for Wake Surfing is probably a little harder on the engine than other uses. Running the engine in this manner generally means the the throttle is further open and the fuel system is providing more fuel than it normally would at that RPM. Sometimes this excess fuel runs past the piston rings and contaminates the engine oil. In severe situations, there is enough unburned fuel in the oil that the oil level in the oil pan actually increases.
If all you ever did was Wake Surfing you might end up with this "making oil" condition. Most people vary the operation of their boat and get an opportunity to run at higher RPM for periods of time that lets the oil heat up and allows the contaminants to evaporate. We recommend that for the customers that run on small ski lakes or never operate their boats at higher RPM that they change their oil more often (25 hours instead of 50) to get rid of the contaminants.
The operating condition that the engine experiences during Wake Surfing can also result in more than normal cylinder and ring wear. The excessive amount of fuel washes the oil off the cylinder walls and increases the friction in the cylinders which increases wear. Again, if all you ever did was Wake Surfed you might see a problem. As long as you vary your operation and "open it up" once in a while, you shouldn't see any detrimental effects from enjoying your sport.
__________________
Larry Engelbert
Indmar Marine Engines"
"Running the boat heavily loaded at low RPM like you do for Wake Surfing is probably a little harder on the engine than other uses. Running the engine in this manner generally means the the throttle is further open and the fuel system is providing more fuel than it normally would at that RPM. Sometimes this excess fuel runs past the piston rings and contaminates the engine oil. In severe situations, there is enough unburned fuel in the oil that the oil level in the oil pan actually increases.
If all you ever did was Wake Surfing you might end up with this "making oil" condition. Most people vary the operation of their boat and get an opportunity to run at higher RPM for periods of time that lets the oil heat up and allows the contaminants to evaporate. We recommend that for the customers that run on small ski lakes or never operate their boats at higher RPM that they change their oil more often (25 hours instead of 50) to get rid of the contaminants.
The operating condition that the engine experiences during Wake Surfing can also result in more than normal cylinder and ring wear. The excessive amount of fuel washes the oil off the cylinder walls and increases the friction in the cylinders which increases wear. Again, if all you ever did was Wake Surfed you might see a problem. As long as you vary your operation and "open it up" once in a while, you shouldn't see any detrimental effects from enjoying your sport.
__________________
Larry Engelbert
Indmar Marine Engines"
Comment