Yachting Monthly - April 2016

technical

82 http://www.yachtingmonthly.com APRIL 2016

As emission regulations tighten up,

Nigel Calder warns of potentially dire

consequences for new yacht engines

Reasons

to be

paranoid

about fuel

I

n recent years, many sailors

have expressed concerns to

me about their vulnerability

to unrepairable-at-sea

engine failure, about

electronic control systems, and

about high-pressure common

rail (HCPR) injector systems

and other modern engine

technologies landing on our

yachts. My response has been

that there is no need to be

concerned, as we have had this

kind of technology in our cars

for years. I’ve come to realise,

however, that the core issue

is not the electronics but the

extraordinarily high fuel system

pressures in combination with

inconsistent fuel supplies. There

are millions of HPCR engines

in service in cars and trucks,

which would suggest there is no

problem, but given the incredibly

tight tolerances necessary

in the fuel supply, sailors are

peculiarly vulnerable because

we take on fuel from many

different places all over the world

with variable cleanliness and

chemical properties and we then

frequently let this fuel sit in our

tanks for months, and sometimes

years, at a time.

How did we get here?

Progressively stricter emissions

regulations over the past couple

of decades have driven, and

continue to drive, radical changes

in diesel fuel supplies and in

diesel engine fuel injection

technology. These changes have

profound consequences for boat

owners now and in the future.

The rapid pace of change is

producing some unforeseen

side effects (including the

Volkswagen emissions test

cheating scandal). In particular,

changes in the chemistry of

diesel fuel and the nature

of injection processes are

creating challenges for the

fuel distribution and filtration

industries which are not always

well met, and which have

outpaced the ability of regulatory

agencies to keep up. The result

is a significant, and potentially

expensive, vulnerability for end

users, especially for boat owners

with new diesel engines.

PHOTO: Nigel Calder

A typical secondary filter (supplied by the engine manufacturer) on a

small marine diesel. Without extra primary filtration, this is completely

inadequate for cleaning up the fuel supply and protecting the engine

PHOTO: graHaM SNOOK/YM

Engine design and evolution may cause problems for boat owners in the future