Yachting Monthly - April 2016

TRIED & TESTED

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

Fuel-Guard

FDG1120 fuel

polishing

system

The dreaded diesel bug

can infest our fuel without

warning. Jonty Pearce

tests a way of fi ghting it

Diesel fuel quality looms increasingly large

among the problems all boat owners face.

‘Diesel bug’ microbes and their effl uent result

in sludgy deposits, ready to block our fi lters

and stop our engines at an inconvenient

moment. Biodiesel is more hygroscopic

(water-absorbing) than petroleum diesel,

so fuel producers blend it with petrol-diesel.

Currently, up to 20% of diesel in the UK

Price FGD100 Standard Filter £199

FDG1120 Water Detection System £255

FDG1120 and Polishing Kit £340

Contact Fuel-Guard

Tel 01908 230579

Web http://www.fuel-guard.co.uk

I regard this

as an essential

piece of kit.

It is well

thought-out

and engineered, needs no

replacement fi lters, and is

easy to fi t. The FDG1120 will

not only keep the diesel in

the tank clean, but also adds

another layer of fi ltration

when the engine is in use.

OUR VERDICT

PROS

■ Washable fi lter –

no ongoing costs

■ Audible, visible alarm

if water accumulates in

fi lter bowl

■ Visible fi lter through

the bowl – dirty

deposits can be seen

■ Fuel actually used

by the engine is also

fi ltered

7/

Before installing the FDG1120, I ‘dry fi tted’

it. The system is installed upstream of the

engine’s existing primary fi lter

The FDG1120

installed on

the front

bulkhead of

my engine

compartment

• the pump is
  behind the
  engine

I mounted

the water

detection

system

alarm by

the main

battery

switches

and Europe can be biodiesel. The problems

start once the fuel is dispensed into our fuel

tanks. For motorists and commercial users who

replenish their tanks regularly there is little

risk. For those of us who do not use a tank

of fuel every six weeks, the risk of diesel bug

infestation rises.

My 36hp Bukh engine only sips at the 260

litres of diesel in my tank; I only use half a tank

every season. The unused fuel sits over the

winter while the biodiesel attracts moisture,

allowing the bug to develop.

Add a bit of water condensation

and the bottom of the tank

provides what the fuel bug

needs for an orgy of proliferation

and fi lter blockage.

Buying fuel from a reputable

source and keeping tanks full

helps, but a fuel polishing

system is a more reliable way to stay bug free.

Fuel-Guard’s system is centred on its FDG100

fi lter, which has a 30-micron stainless steel

fi lter element and water separator. The FDG1120

has a water sensor, the polishing kit includes a

pump and a collection of fuel hose, stop valves,

T-pieces and connectors. All I needed to add

was my choice of electronic timer and a couple

of connector adaptors and hose barbs to suit

my rather ancient fi ttings.

With planning and forethought, installation

was child’s play. I connected the system via a

T-piece and stop valves to the existing primary

fi lter on the forward engine bulkhead. The

‘polishing arm’ off the T- piece was connected

by the supplied fuel hose to the pump screwed

The FDG1120

Polishing kit with

water detection

system, as supplied

by Fuel-Guard

to the side bulkhead, and this polishing

return was fed into the fuel return line via

another T-piece and stop valves.

The next step was wiring the electrical

supply for the pump, timer and water sensor.

I connected the timer and power supply to

the house ‘bypass’ fuses alongside the bilge

pump supply – this system

preserves the gas alarm and

bilge pump, when the house

battery isolator is turned off.

I’ve set the timer to turn on

for two hours a week. When

the system is running I hear a

reassuring buzz from the pump

and the splash of the returning

fuel. I do have to remember to turn off the

timer and turn the stopcocks to ‘Engine’

when I arrive on the boat – and similarly, on

leaving, the timer must be activated and the

stopcocks set to ‘Polish’.

How often the fi lter will need to be

cleaned remains to be seen – it is washable –

and any separated water can just be drained

away at the bottom of the fi lter.

CONS

■ It would be wise to

continue to use

fuel additives

■ The valve positions

need to be changed on

arriving/leaving

the boat

■ The pump is audible

when polishing fuel –

though this may

be a good point!

‘With a little

planning,

the installation

was child’s play’

PHOTOS: JONTY PEARCE