Whats the best propeller for my Indmar Engine?
Your engine should be propped so that it operates at or near the top end of its recommended rpm range at wide-open throttle with a normal boatload (fuel, gear, people, etc.) An engine that does not reach the rated RPM at wide-open throttle is in an “over propped” condition, resulting in “lugging”. This high-torque operation puts a tremendous load on the pistons, crankshaft, and bearings. Even if you may seldom operate your boat at wide-open throttle, the engine bust be able to operate in the specified range. On the other hand, an engine that revs past the recommended RPM will have higher than normal wear and can also be damaged. All Indmar EFI engines have RPM limiters set to prevent the engine from over-revving. Indmar carbureted engines do not have RPM limiters so care must be taken to avoid allowing the engine to exceed the maximum RPM. Propping is not an exact science and may require some trial and error. The maximum RPM your engine can achieve is dictated by propeller pitch. Gener
Your engine should be propped so that it operates at or near the top end of its recommended rpm range at wide-open throttle with a normal boatload (fuel, gear, people, etc.) An engine that does not reach the rated RPM at wide-open throttle is in an “over propped” condition, resulting in “lugging”. This high-torque operation puts a tremendous load on the pistons, crankshaft, and bearings. Even if you may seldom operate your boat at wide-open throttle, the engine bust be able to operate in the specified range. On the other hand, an engine that revs past the recommended RPM will have higher than normal wear and can also be damaged. All Indmar EFI engines have RPM limiters set to prevent the engine from over-revving. Indmar carbureted engines do not have RPM limiters so care must be taken to avoid allowing the engine to exceed the maximum RPM. Propping is not an exact science and may require some trial and error. The maximum RPM your engine can achieve is dictated by propeller pitch. Gener
