Fuel contamination

[Waihaka]

I purchase fuel from busy petrol station (Australian term for where you buy gas/fuel) in 20 litre containers and siphon into our 400 litre tank. The siphon hose is clear so I can see it going in and it looks clean and normal.

A new injection pump had recently been fitted prior to the start of our journey from Melbourne (Mainland Australia) to circumnavigate Tasmania (Australia’s largest island). Some 20 hours into the journey we had a diesel runaway with the motor revving to the point of destruction. Returned home under sail to find the injection pump corroded beyond repair. The fuel had become discoloured and on analysis was found to be very corrosive.

There is no current explanation for why the fuel had been contaminated with my only thought being I had added some older biocide. Just wondering if the brains trust could come up with alternative explanations.

The end result has been having to replace what had been a reliable engine with a new one and the failure of a trip that had been 12 months in the planning.

[Kettlewell]

Older fuel in the bottom of the tanks could have been a breeding ground for crud. You may have picked up contaminated fuel previously, and/or seawater may have entered the fuel tank through a leaky deck plate. Per previous Practical Sailor reporting I use a combination of StarTron diesel treatment (corrosion) and Biobor treatment (kills fungi and bacteria) in every new load of fuel. Do you have a big primary fuel filter like a Racor with a clear bowl at the bottom? Worth it to periodically drain a sample from the bottom of that and take a look for water and bacterial contamination. Your primary and secondary filters should be capable of filtering out most of the crud before it reaches the injector pump.

[Iron E]

Most of what you're explaining sounds like saltwater in the tank/fuel. Fuel vents and caps should be checked

Did you fill your tank completely to the 400 liter mark?
Do you have quality water separators that are properly installed?

I'm not certain about the injector pump being corroded beyond repair. I would like to know the details of the damage.

Sorry about your trip.

[skipperpete]

Originally Posted by Waihaka

I purchase fuel from busy petrol station (Australian term for where you buy gas/fuel) in 20 litre containers and siphon into our 400 litre tank. The siphon hose is clear so I can see it going in and it looks clean and normal.

A new injection pump had recently been fitted prior to the start of our journey from Melbourne (Mainland Australia) to circumnavigate Tasmania (Australia’s largest island). Some 20 hours into the journey we had a diesel runaway with the motor revving to the point of destruction. Returned home under sail to find the injection pump corroded beyond repair. The fuel had become discoloured and on analysis was found to be very corrosive.

There is no current explanation for why the fuel had been contaminated with my only thought being I had added some older biocide. Just wondering if the brains trust could come up with alternative explanations.

The end result has been having to replace what had been a reliable engine with a new one and the failure of a trip that had been 12 months in the planning.

The obvious possibility is that the containers already had a contaminant in the bottom when you filled them, (pool chemicals, battery acid, bleach) but whatever it was, it must have been very aggressive to rapidly corrode a new injector pump. What engine do you have in your boat ( did you buy the Oyster42?) .Any reason why the injector pump was replaced rather than repaired and was the old pump corroded? Who did the fuel analysis? Sorry about all the questions, hopefully the forum can come up with some answers about the fuel contamination.

[thinwater]

Originally Posted by Waihaka

I purchase fuel from busy petrol station (Australian term for where you buy gas/fuel) in 20 litre containers and siphon into our 400 litre tank. The siphon hose is clear so I can see it going in and it looks clean and normal.

A new injection pump had recently been fitted prior to the start of our journey from Melbourne (Mainland Australia) to circumnavigate Tasmania (Australia’s largest island). Some 20 hours into the journey we had a diesel runaway with the motor revving to the point of destruction. Returned home under sail to find the injection pump corroded beyond repair. The fuel had become discoloured and on analysis was found to be very corrosive.

There is no current explanation for why the fuel had been contaminated with my only thought being I had added some older biocide. Just wondering if the brains trust could come up with alternative explanations.

The end result has been having to replace what had been a reliable engine with a new one and the failure of a trip that had been 12 months in the planning.

I'm a chemical engineer in that industry. Either post or PM me the test results.


Yes, a leaky filler cap is always the most likely cause. But there are many others. Old biocide is not likely one of the causes.

[Waihaka]

Further information regarding my post.
1. We have Raeco primary and secondary filters that showed neither water nor biological growth in the fuel. They however collected evidence of corroded metal with a rust like colouring.
2. The plastic containers were new and only used to transport the diesel.
3. The engine, a Volvo/Perkins has been meticulously serviced every 100 hours.

[boris]

What are your tanks made off are they Steel?

[Tin Tin]

Was that a brand new Volvo OEM inector pump - you are saying this got corroded beyond repair in 20 hours.? Is it a turbocharged engine? What year?

[skipperpete]

Originally Posted by Waihaka

Further information regarding my post.
1. We have Raeco primary and secondary filters that showed neither water nor biological growth in the fuel. They however collected evidence of corroded metal with a rust like colouring.
2. The plastic containers were new and only used to transport the diesel.
3. The engine, a Volvo/Perkins has been meticulously serviced every 100 hours.

Why did you need a new injector pump? What happened with the original “meticulously serviced” one.

[thinwater]

Originally Posted by Waihaka

Further information regarding my post.
1. We have Raeco primary and secondary filters that showed neither water nor biological growth in the fuel. They however collected evidence of corroded metal with a rust like colouring.
2. The plastic containers were new and only used to transport the diesel.
3. The engine, a Volvo/Perkins has been meticulously serviced every 100 hours.

1. Bio contamination is determined with a culture, not appearance alone. A dip slide would need to be used for proof. If the fuel is acidic, bacteria are the most common reason.


Seawater + copper plumbing can build a corrosive mixture. Steel is also a part of the equation.


Sail Delmarva: Are We the Cause of Fuel Breakdown?


We need more information.

[Waihaka]

Our boat is an Oyster 42 with the composite tanks being an integral part of the hull. The testing didn’t reveal biological growth.

[SailingHarmonie]

Originally Posted by Tin Tin

Was that a brand new Volvo OEM inector pump - you are saying this got corroded beyond repair in 20 hours.? Is it a turbocharged engine? What year?

Another chemical engineer here... that 20 hours from new to total failure from corrosion premise just sounds implausible in the extreme. It is hard to come up with chemistry to have diesel fuel be THAT corrosive without lots of water around, and water that was severely contaminated as well.

A bit more out of the range of my formal qualifications, but ... the idea that a corroded injection pump was the cause for a runaway also sounds strange. Are you 100% sure that the issue was the fuel and not the motor oil???

Oh, and also important to know... why was a new injection pump fitted? It is very rare that an injection pump is "beyond repair". I am wondering if there is a common thread? I have had many injection pumps rebuilt, but never had to replace one with new. It could happen, but it is very rare. Having TWO die on the same engine in a short time seems like way more than a coincidence.

[skipperpete]

Originally Posted by Waihaka

Further information regarding my post.
1. We have Raeco primary and secondary filters that showed neither water nor biological growth in the fuel. They however collected evidence of corroded metal with a rust like colouring.
2. The plastic containers were new and only used to transport the diesel.
3. The engine, a Volvo/Perkins has been meticulously serviced every 100 hours.

Just because the containers were “new” doesn’t guarantee that they weren’t contaminated and I’m still confused over the corroded injector pump, it would be reasonable to assume that the injector lines, injectors and fuel filters (Racor? Ryco?) would also be showing signs of damage or destruction from corrosion. The engine overspeed however, is easily explained and a fairly common event with the type of cassette injector pump fitted to kubota and Shibaura (Volvo,perkins, northern lights, Cat. )engines. If one plunger seizes at full fuel, the rack holds the other 3 in that maximum delivery mode unable to be controlled by the governor or the stop control. If the engine was still in gear it might be possible to keep it engaged until the fuel could be cut off, a 4 cylinder volvo running on 3 at overload fuel couldn’t develop enough power to overspeed while the propeller is still engaged but there might be a fair bit of black smoke
It would be very ambitious to think that you could see contaminated fuel running through a plastic siphon hose ,….unless if it was really foul ….. maybe, but even a 50 micron particle would be practically impossible to spot as it raced along that clear hose.
There remains the possibility that the fuel suction and return lines are crossed and unfiltered fuel was being delivered to the engine …but this would need a return line from the bottom of the tank and no secondary filter between the lift pump and the injector pump to actually happen and even then its a very very unlikely scenario.

[thinwater]

Originally Posted by Waihaka

Our boat is an Oyster 42 with the composite tanks being an integral part of the hull. The testing didn’t reveal biological growth.

What does "very corrosive" mean? You didn't share the analysis, other than no bio growth (but didn't say what test method).

• Salt?
• Water?
• Very low pH?

Normally, really quick damage to an injection pump requires running a level of seawater through it. If there was no bio growth, very low pH seems unlikely.

[Tin Tin]

Maybe someone poured some holding tank cleaner down the wrong filler.