Online Book:

Engines For Cruising Boats

Matt, AAC Engineering Correspondent, starts this Online Book with an in-depth look at what makes an efficient powertrain and how we can benefit from future developments.

John then shares his experience gained in three re-powers and twenty years of cruising the Arctic, where a reliable engine is literally a lifesaver, including a step-by-step account (with many photographs) of the latest and highly successful repower of Morgan’s Cloud.

If you own a boat with an engine—auxiliary sail or power—you will benefit from reading this, even if you only use the knowledge to better manage your existing engine and, into the bargain, make it last longer and break down less often.

Table of Contents:

Understanding An Engine Fuel Map

fuelmap_target60

Matt explains those graphs that adorn engine brochures and manuals. Understanding these diagrams is the key to better fuel economy and less problems with your diesel engine.

What Marine Engine Duty Ratings Mean To You

Fuel map for 105, 90 and 70 kW versions of the same 4 litre diesel engine

Just what is a "commercial" or "continuous" duty rating on an engine, and should I get that?

Matt starts with the reason that these ratings exist, and then moves on to how to select the correct engine duty rating for a displacement boat.

Propeller Efficiency

Antifouled prop - before and after  147 IMG_3950

Matt brings his customary clarity to a complicated subject: propellers. Reading this post will cause you a bit of brain sweat, but doing so can help you get big gains in engine efficiency.

Controllable Pitch Propellers (CPPs)

CPP several

So far in this Online Book we have learned about the fundamentals of engine and propeller efficiency and, in the last chapter, we looked at a way to make our existing engines a bit more efficient. In this chapter Matt explains a much better way to get the very most out of every drop of diesel fuel.

Engine Installation—The Devil Is In The Details

Morgan's Cloud's engine room showing new engine installation.

John, who has done three of them, fervently hopes that this will be his last repower. Read along as he spends three months fulltime at one of the best diesel repower shops in the world, sweating the details to make this installation the best it can be.

New Engine, The Proof is in The Voyage

JHHGH1_0971.jpg

So how did the new engine work out over time? What worked well and what did not? It's all here, together with solid recommendations for transmissions, exhaust systems, and drive line.