When running on power only my 376 cruises at 6 knots at 2,800 rpm. I have an adjustable 3 blade Max Prop and I am considering adjusting it to the next higher pitch. I would appreciate to hear others speed to rpm experience and what is the max rpm for an extended time ? The Yanmar Operation Manual states "Continuous rating output" of 34.9 hp @ 3,400 rpm, but that seems to be a high rpm to run at. Comments please. Thanks. Ray
Yanmar rpm
- Thread starter Ray18670
- Start date
- Status
80 Percent of Max RPM
Trust your manual. The west coast Yanmar distributor said keep it in the range of 80% of you max RPM rating which you should be able to achieve if you are propped correctly. These diesels are designed to run at those RPM's and like to; less deposits, etc. At least that's what he said, and is consistent from reports of others on this board who have attended classes in other areas. Rick D.
Trust your manual. The west coast Yanmar distributor said keep it in the range of 80% of you max RPM rating which you should be able to achieve if you are propped correctly. These diesels are designed to run at those RPM's and like to; less deposits, etc. At least that's what he said, and is consistent from reports of others on this board who have attended classes in other areas. Rick D.
What Model Engine Do You Have?
And...does your engine smoke (black) at that rpm while under load?
And...does your engine smoke (black) at that rpm while under load?
Hull Speed ?
With your hull speed of 7.58 (1.34* sqrt(LWL)) and no smoke you may be slightly underpropped. Overpropped would generate black smoke. IMHO, you may not be generating the necessary thrust (at 80% of max rpm) to achieve hull speed. Looks like time to experiment with it. My 3-cyl Yanmar (3HM35F) has a top rpm of 3400 (80%=2720rpm) and I just make it with the standard 2-blade prop.
With your hull speed of 7.58 (1.34* sqrt(LWL)) and no smoke you may be slightly underpropped. Overpropped would generate black smoke. IMHO, you may not be generating the necessary thrust (at 80% of max rpm) to achieve hull speed. Looks like time to experiment with it. My 3-cyl Yanmar (3HM35F) has a top rpm of 3400 (80%=2720rpm) and I just make it with the standard 2-blade prop.
full rpm
What rpm does the engine achieve when at full throttle in neutral also in gear and up to speed?
What rpm does the engine achieve when at full throttle in neutral also in gear and up to speed?
- Status