a curious case of sticky fuel
River Canal Rescue reports there’s been an uncharacteristic peak in fuel-related component breakdowns not linked to diesel bug. It cites two identical jobs where fuel injectors were diagnosed as needing an overhaul, yet their replacements stopped working within a week, and injection pumps were found to have failed even though the diesel was clear and bright.
Upon further investigation, RCR engineers found in both cases the injector pump racks had seized solid and the nozzles were blocked, and when replacing the plunger filter head, they found the fuel had a sticky, syrup-like substance. Alongside stuck injection pump racks, injectors and filter head plunger failures, RCR is seeing cases of fuel filters blocking with wax inside them.
Managing director, Stephanie Horton, explains: “Over the last nine months we’ve come across higher than normal call-outs for injector, injection pump and fuel problems not related to diesel bug. Our contractors are also reporting reoccurring issues with these systems and ‘sticky fuel’.
“It’s definitely a type of contamination, but not one we’ve seen before. Samples have been taken and we’re trying to build a picture of the problem. Our engineers are reporting problems across the UK and this particular issue is only becoming clear when a fault reoccurs, because the diesel on the whole, looks bright and clear.
“Initially we suspected sugar in the fuel, but sugar stays crystalline instead of dissolving. We now believe it may be related to a reduction in FAME free fuel and a change in fuel and fuel treatment additives.”
In order to identify the culprit, Stephanie is keen to hear from boat owners and engineers with similar problems: “I want to learn more about their experiences, where they filled up and what treatments they may have used, and increase my sample size. The more I know, the closer I am to finding a solution.”
Stephanie believes the issue could stem from chemicals, now present in some treatments and red diesel, which replaced banned additives, and she’s looking into the farming sector’s blocked fuel filter problems reported around a year ago.
According to Farmers Weekly, in order to increase the proportion of fuel derived from renewable sources (capped at 7%), an increasing amount of biodiesel was blended with red diesel. Known as Fatty Acid Methyl Ester - FAME – it’s made from a combination of fresh and recycled vegetable oils and some animal fats.
The blockage problems were initially attributed to its storage, but differing regional cases discounted this. The UK Petroleum Industry Association (PIA) tested samples but failed to pinpoint a single cause. However tests by a fuel additive producer showed there could be a problem with insolvable particles dropping out of some of the fuel blends.
After testing 100 fuel and clogged filter samples, only 15% were found to contain contaminants as a result of poor storage, and in many cases, they weren’t significant enough to cause a blockage. The remainder were contaminant free with a clear appearance.
More detailed tests revealed the fuels had high total contamination levels and particulate counts, many between 15-20 mg/kg. Clean gas oil normally has a contamination level of 6mg/kg and the legal limit is 24. When an external lab tested the sticky residue it revealed the problem was caused by sterol glucoside and monoglyceride particles.
These substances can drop out of bio diesel components and the problem’s made worse at low temperatures. They can also easily accumulate as they don’t melt back into the fuel as the temperature rises. With FAME coming from multiple sources, the PIA says fuel producers are working to address the issues by changing the properties of their diesel fuel blend.
Stephanie continues: “There’s an industry task force currently looking at sustainability and the use of second stage bio-diesel for marina applications and they report these ‘sticky fuel’ symptoms were reported in their testing samples when using first stage bio-diesels. It’s clear there’s an ongoing problem which I wonder may be due to marinas no longer being able to supply FAME-free oil.
“It’s important we get to the bottom of the problem as these are costly breakdowns and business are also at risk due to the reoccurrence of issues and covering repairs under warranty.”
Stephanie is asking anyone experiencing ‘sticky fuel’ issues to send in samples or get in touch with River Canal Rescue: “Please give your name, email address, a date when the issue occurred, when you last filled up with fuel and where, plus information on whether any treatments were added to the fuel and if so, what type.”
Letters should be addressed to: Fuel Samples, River Canal Rescue, 11 Tilcon Avenue, Baswich, Stafford ST18 0YJ, email: with fuel issues in the subject line or call 01785 785680.

I now live and work on a travelling narrowboat business. I began as ‘Cake on the Cut’ making homemade cakes, hence my Salted Caramel Gin. But I have slowly evolved into ‘Gangplank Spirits & Preserves' and I make foraged fruit gin, whisky, rum, vodka, chutney, jam & cordial. I also open as a café selling soft drinks and crepes, and I have a fully licenced bar.
I’ve been boating 15 years now and I’m still very in love with the lifestyle. The towpath is a friendly place where people like to talk to each other and help each other out. Most boaters are unmaterialistic and happy with the simple things in life, a fire, good company, a stew in the pot, and a pint.
The everyday small adventures are just as fun, all the windy rainy days, being blown across the cut, fallen trees blocking the canal, single handing swing bridges that open on the wrong side, going down the weed hatch for the third time in a day...
This year has been one of the most difficult I’ve ever had on the cut. I had to have a complete re-plate of my boat during lockdown and borrow the money in one of the most financially challenging years for my business.
Fortunately this has been more than compensated for by the number of super generous people who have gone out of their way to support me and my small business, and realising more than ever what fantastic friends and family I’m lucky enough to have.
The public have been incredible, people have really been trying to support the small business owner for which I am immensely thankful. They have literally kept me afloat.



The Rose of Hungerford is a traditional canal boat offering public trips and private charters, owned by the Kennet and Avon Canal Trust and run and maintained by fully-trained volunteer members of the Hungerford branch.
The current Duke of Lancaster is Her Majesty the Queen. She travelled on The Rose when officially opening the restored Kennet and Avon Canal at Caen Hill, Devizes, on 8th August, 1990, 30 years ago. In 2013, The Kennet and Avon Canal Trust was honoured by Her Majesty, who awarded the Queen’s Award for Voluntary Service, the MBE for voluntary groups. In 2014, The Princess Royal visited the Trust’s Headquarters in Devizes to present the Award.
I live on, work in and sell from my little boat ‘Fern’. I am a painter of fauna and flora and resident artist at Fern Floating Fine Art. My work is influenced by folklore, superstition, fireside tales, canal and traveller traditions, the macabre, Victoriana, and I take constant inspiration from the seasons and the countryside around me.
I like to separate my subjects from their everyday existence and instead venerate them to icon status by infusing them with vast amounts of symbolic flora. I pay no regard to accurate or relative proportion, instead preferring to use this to further separate the subject by using the flowers to create busy almost abstracted backgrounds. This technique and my use of colour is very much influenced by my traveller culture where almost everything is highly decorative. My paintings reflect rather than illustrate the stories that I come across through my travels.
Shiam and John Wilcox sell from their narrowboat wherever they happen to be on the waterways.
Staff from waterways and wellbeing charity, Canal & River Trust were on hand to give a warm waterways welcome to their new neighbour Steph McGovern. Today, the former BBC Breakfast presenter launched her new daily lunchtime television show - Steph’s Packed Lunch.
Local boater Caleb Price and his wife Fiona were also on hand to cheer from their narrowboat. Caleb was one of the first to bring his boat into the newly regenerated Clarence Dock area almost quarter of a century ago, with the 1996 opening of the £42.5million purpose-built Royal Armouries Museum.