Engine RPM

[SnaxMuppet]

What RPM should I be running my yacht diesel engine at?

I have a Volvo 2020 engine. It seems quite happy at about 2800 RPM which gives us about 5.8kts but I wondered if I could run it a little harder if required?

 

[fireball]

It should have a max RPM written on the engine - Ours is ( I think!) 3600 for a Yanmar 2GM20 ... we run at 3200 if we're pushing it, or 2.8 for a comfortable ride...

 

[boatmike]

Diesels like to work and you will not do any damage by running at full throttle but the most economical speed in terms of fuel consumption will probably be about 80% of this.

 

[spannerman]

The rule of thumb usually is max throttle minus 2-300 rpm to be kind to the motor, for best economoy back off 4-500 rpm. Depending on motor/conditions/hp.

 

[Sans Bateau]

I believe I am right in thinking that you are more likely to damage a diesel engine continually running at low revs, rather than nearly flat out. Also there will be a govnor in the engine, this will be set by the manufacturer at a speed that you cannot exceed

 

[alb40]

Tis true, diesel do not like being run lightly loaded.

On the other hand, they do not like being overloaded either, so make sure your engine can pull up to close its specified maximum rpm in addition to the oter points. Continuous full throttle will also kill a diesel, so as others have said, back off a little from full bore, and this will provide the ideal fast motoring condition for the engine.

 

[tome]

Sounds about right to me. We have a VP2030 which we tend to run at 2600 (max 3200) for reasonable economy

 

[jackho]

I had a 2030 engine from new and asked Volvo the same question also coupled to my prop size. They said the max. RPM should be 3500 so open throttle full and if prop size is correct you should not exceed 3500. Assuming your boat is a standard production yacht then I guess this should also applyin your case!!