Help with Fuel Management

We explain Fuel Management in 2 easy to follow steps.

A closer look at our Fuel Management

Here at MarShip, we want to help you prolong the efficiency of your diesel engine.  We have products to maintain the vital elements of your engine, The Air, Fuel & Oil.

Today we are taking a closer look at "The Fuel"

The best advice we can give you is to have a fuel management routine. Whether you are a single vessel owner or manage a fleet, this should be key to your operation.

This is not a complicated process in fact, it can be broken down into 2 easy steps.

1. Remove the water, either via the drain or with a dewatering device.

2. Dose with the correct additive.


Water is the enemy and must be removed from your fuel before it enters your engine.  ALL tanks have water at the very bottom.  It enters your tank in various ways including from the supplier, absorption from the atmosphere, or sometimes from just deck washing.  Water is heavier than diesel, so it falls to the bottom of your tank.

When water is present, diesel bug will breed. We talk lots about diesel bug, but to summarise, it is a combination of yeast, mould and bacteria.  It displays as a stringy black slime, it breeds extremely quickly and will stop your engine.  To read more about diesel bug, click here

To recap,the water will sink to the bottom of your tank – meaning it is beyond the reach of your water separator which connects at the fuel suction - this is never at the lowest part of the tank.  You may get water in your glass bowl, this will happen when underway and the contents of the tank are sloshed around, but it will not effectively remove all traces.  If you see water in your glass bowl, then you definitely have a lot more water on the floor of your tank.

If your tank has a drain valve, it is imperative you use it on a regular basis – this will remove water from the fuel and prevent diesel bug from taking hold and stop water entering your engine.  No water = No diesel bug.

If you do not have a drain, we strongly recommend a dedicated diesel de-watering system ….

Diesel De-watering System

If your tank is not fitted with a drain, then consider fitting a Diesel Dipper®

The Diesel Dipper® has one job – to remove water from diesel.  It is fitted with a 12v pump (24v version available) and gently lifts the water and debris from your tank while underway.  It is used independently of the engine.  

It works by sucking the fuel into the tank separator (patent pending) where it separates out any sludge and water to be drained manually, the fuel then passes through a washable fine filter before clean fuel is returned to the tank.  Click here for an animation and video demonstration or see foot of this blog.

Use with our Dip Tube assembly if no drain to suck from the bottom of the tank.  

It can be installed by anyone with reasonable DIY skills and is supplied with 3/8 BSP connection and 10mm hose tails.

The final piece of the puzzle, but equally important, is to …

Dose with a fuel additive.  

Even if you can remove water from your tank,either via the drain or a de-watering system,

Using a fuel additive is now more important.   The sulphur content in fuel acted as a natural lubricant, but now the sulphur has been removed, diesel is dry and lacking in lubricity.  It is also more prone to harmful deposits and diesel bug.

There are so many products on the market, MarShip provide a range of additives including an engine manufacturer approved biocide suited to the size and application of your vessel., so whether you own a pleasure yacht or fleet of workboats, we can help you. More details and useful videos can be viewed here

Contact our friendly team today on 01666 818 791 or send us an email

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Peter Weide is MD of MarShip UK, a UK based company specializing in optimising the efficiency of marine diesel engines. Advising on maintaining the cleanliness of Air, Fuel and Lubricating oil, we regularly recommend solutions to operators and appear regularly in industry press, with our full range of diesel additives DieselAid we can offer solutions for most operating conditions and wont advise them if you don’t need them.

Prolonging Efficiency in Your Diesel Engine