Freebee
Well-Known Member
Perhaps farmers weekly has a useful angle on this problem
Red diesel: The problems uncovered - Farmers Weekly
Red diesel: The problems uncovered - Farmers Weekly
unrefined oil within the diesel
- Thread starter P55ETR
- Start date
Fr J Hackett
Well-Known Member
That's very interesting I will admit that I had not heard of ashphaltines and their being a problem in fuel systems. A quick google doesn't come up with much apart from companies selling remedies so a bit more research is required.
Fr J Hackett
Well-Known Member
Different to ashphaltines, I can see where glucosides could originate from bio derived additives however these all get trapped at the filtration stage so would appear not to be involved in injection pump failure.
Still interesting though.
Freebee
Well-Known Member
it would be trapped by filtration unless as in one case I have seen the return to tank was not returned to the tank but plugged into the fuel feed after the filter
DownWest
Well-Known Member
Seen that too.
But feel that anything that gets through a decent filter system will burn in a diesel, apart from water.
ean_p
Well-Known Member
Wouldn't any 'return' fuel have had to pass through the engine filtration system in the first place before it 'became' returned fuel?
Fr J Hackett
Well-Known Member
And then pass through the filters before it got to the injection pump and injectors?
Freebee
Well-Known Member
Perhaps I was not very clear if the return is passed into the fuel feed after the filter the return is heated fuel, if its continually fed back in like that the fuel just gets hotter and hotter, the temperature will plateau out but in the meantime its cooking and that is when solids can be released.
Fr J Hackett
Well-Known Member
I understand what you are saying but why on earth would anyone arrange a fuel return like that.
LittleSister
Well-Known Member
But connecting the excess fuel return to the incoming fuel line is recommended against, so such arrangement are presumably not common.
It would explain the single case that Freebee cites, but not the rash of failed injector pump cases with a mystery cause that RCR claim to have uncovered.
It would explain the single case that Freebee cites, but not the rash of failed injector pump cases with a mystery cause that RCR claim to have uncovered.
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Corona Mia
Well-Known Member
I don’t think you have any realistic chance of getting ‘unrefined oil’delivered to your boat by a reputable suppl
I would be surprised that you‘ve received any ‘refined oil’ from a legitimate mineral oil (crude oil) refinery.
Everything is separated and very specifically tested for ’grade’ and ‘contaminants’ before it leaves the refinery.
Maybe ‘Refueler’ could comment?
Of course it’s possible that your fuel suppliers may have ‘blended’ other refined fuel streams into your delivery.
Or maybe attempted to blend ‘bio content’ into the fuel.
Normally the biggest cause of fuel problems is water content in the fuel.
High pressure fuel pumps and diesel injectors don’t like water!
If you’ve never drained you tank it could be sitting there waiting to be sucked-up as diesel is lighter than water and will ‘lurk’ in the bottom of your tank.
Maybe it comes from your suppliers tanks……..but it’s unlikely to be ‘unrefined oil’.
LittleSister
Well-Known Member
Interesting report (cum advert!) providing some background, but the only problem it mentions is blocked filters, not the wrecked injector pumps this thread was discussing.
Mistroma
Well-Known Member
I have mentioned before that I remove residue from the tank sump twice a year. I was finding about 0-2mls in 2012 and it increased steadily over the years. I now remove a lot more (perhaps 20-30mls) and a litre or so of cloudy fuel. It settles quickly to clear fuel with a small residue. I think the 20-30 mls ends up more like 10-20mls once it has settled. I only have a 130 litre tank with about 30 litres over winter and hope that gives a rough idea of the scale.
I have always considered this "normal" degradation products (e.g. Asphaltenes) as that's what it looks like. Certainly not "bug", just a dark oily residue. It doesn't grow over the winter and just settles out with long storage. I don't get anything in stored fuel. Both tank and anything in a can are treated with Marine16 pre-layup.
I tend to leave the tank almost empty over winter as it is plastic and I make certain the filler o-ring is a very good seal.
My Yanmar feeds a lot of excess hot fuel back to the tank. The tank gets pretty hot after very long runs here in Greece and I've always assumed that's the reason for the degradation with current fuel. I never noticed the problem in Scotland but it's colder there, I did shorter engine runs and was using red in those days (2009-2011). Cold weather and shorter runs were probably the most important factors in those times.
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jdc
Well-Known Member
Asphaltenes have been a cause of black crud in fuel for 20 years. They are a normal decomposition product of ULSD.
Nobody makes any fuss about this, but our switch to ULSD has been the biggest and most important change to diesel fuel in 50 years. Besides this, FAME, aka biodiesel, is a trivial change.
ULSD changes the oil we should use, it changes the decomposition products and appearance, and is, imho, about 10x as common a problem as the semi-mythical 'bug'. LOADS of references, some on this forum.
Nobody makes any fuss about this, but our switch to ULSD has been the biggest and most important change to diesel fuel in 50 years. Besides this, FAME, aka biodiesel, is a trivial change.
ULSD changes the oil we should use, it changes the decomposition products and appearance, and is, imho, about 10x as common a problem as the semi-mythical 'bug'. LOADS of references, some on this forum.
Refueler
Well-Known Member
Your insistence on saying ULSD is ????
ULSD is basically same refinery product but has two processes extra :
1. Sulphur washing - to reduce sulphur content
2. Addition of Lubricity additive if needed.
Other than that generally its gasoil.
Ashphaltenes ... is part of the spec requirements and strictly monitored / limited.
Changes the Oil you use ? Why ? In fact ULSD should aid any oil you use because it will produce less corrosive by-products to contaminate the oil.
jdc
Well-Known Member
I agree entirely that it produces less corrosive by-products, hence the oils we are recommended too use should have changed, eg rather than CF which many manufacturers still specify, they might have changed advice to recommend oils such as CF-4, but engine manufacturers paid it no attention and never amended their manuals.
However, although I hesitate to push it when you are much more expert than I am on this - the sulphur washing can, or so I understand, result in a less stable oil; one which is more prone to oxidise or be subject to degradation resulting in asphalting deposits after long storage. Lot's of articles about, not all of which are very scientific so an expert view would be welcome; most conflate addition of FAME with removal of Sulphur.
However, although I hesitate to push it when you are much more expert than I am on this - the sulphur washing can, or so I understand, result in a less stable oil; one which is more prone to oxidise or be subject to degradation resulting in asphalting deposits after long storage. Lot's of articles about, not all of which are very scientific so an expert view would be welcome; most conflate addition of FAME with removal of Sulphur.
