Diesel Fuel

What Goes In

Why fuel and fuel system maintenance are important

There’s nothing worse than going to the expense of buying a generator set, then just when you need electric power, it won’t start.  General care and maintenance go a long way to help, but sometimes it’s the things which are easiest to solve which cause problems – like fuel quality. 

Diesel fuel starts to degrade almost from the moment it’s refined and has a shelf life of 6 to 12 months at most.  During that time, it’s pumped through pipelines, transported and stored and then pumped into your fuel tank. All through this time, natural deterioration, build-up of condensation and opportunities for external contamination can all contribute to decline in fuel quality. And eventually this can cause the build-up in particulates in the fuel which will block or damage filters, fuel pumps and injectors. 

But that’s not the full story:  during its lifetime, like any other organic liquid, diesel fuel starts to deteriorate, usually after about 100 days.  The fuel begins to break down, fall out of solution, cluster up and drop to the bottom of the tank as a dark sludge.  The fuel goes dark, smells bad and makes engines smoke.  This is because some of the clusters can be small enough to pass through filtration and into the combustion chamber:  the outer edges of the cluster get burned there but the rest goes out of the exhaust as unburned fuel.  As these clusters grow, they reduce the flow of fuel by clogging filters and eventually injectors will be ruined.  Over time you’ll see a loss of power, smoke from exhausts and a bad smell of unburnt fuel.  The less often you run your diesel engine, the more quickly these problems can arise. 

The good news is there are some very simple steps you can take to prevent problems. 

Always ensure that you fit genuine filters as specified in your operator manual. It’s tempting to use lower cost filters which fit or to let routine maintenance slip to save money but in the longer term, this is only going to cause problems.  Don’t wait until you see a problem before you think about changing the filters. 

Be careful that you buy fuel from reputable suppliers and that the tanker which delivered your fuel isn’t containing diesel one day and something else the next. 

Keep your tank full of fuel.  This prevents condensation from forming which is the number one cause of algae growth within the fuel tank.

If you don’t run your generator set regularly, remember the shelf life of the diesel in the tank. 

If you own a generator set from FG Wilson, you’ll always have expert help.  Your FG Wilson dealer can support and advise you on all the best practices for fuel system maintenance so that your generator set has a long and productive life. 

For more information on FG Wilson parts, visit https://www.fgwilson.com/en_GB/support/genuine-parts.html