Diesel fuel quality.

doris

doris

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I’m sure there are lots of fuel industry technocrats on the forum that can answer this.

Diesel for cars has become increasingly technically competitive as the manufacturers compete for best economy, best for engine life etc. Is there anything to be gained by using road fuel, with all ongoing hassle about transferring via cans, rather than marine fuel? I presume the latter is old fashioned, bog standard diesel with a serious lack of modern additives.

Discuss/comments
 
I think there is a bit of a divide in that new marine diesels prefer ULSD where as older diesels prefer heavy oil? I heard it mentioned that older engines need the heavy oil for lubrication? not sure if it's true.
 
I would first of all say that I'm not a fuel expert nor a chemist. I've taken advice from an ex-forumite ("SBC") in the past but that's still only received knowledge.

I have used yellow diesel in my 1GM (not a 1GM10) for several years now, although I have no qualms about using red diesel if I need it. The reasons are twofold:
1) It is far less likely to contain diesel bugs than the red stuff sloshing around in tanks on marina pontoons.
2) It aids starting. According to my (our) mutual acquaintance, fuel is specified by its calorific return/ignition temperature. That is why although biodiesel/tractor fuel/heating oil might look and smell like car diesel, it's not quite the same as what you buy at the pump, and there is a real difference between Esso and MDL. Or equivalent. I can say, categorically, that since I started using yellow diesel the Yanmar has been far easier to start, usually just a couple of turns with no extra throttle required in summer temperatures. Whether that's due to higher burn temperatures or cleaner fuel I doubt it's possible to say. Throwing in the odd gallon of red, however, doesn't seem to change that, but I will continue to stick to a winning formula where possible.

The bottom line to No. 1 is that despite clean fuel, tank cleaning and biocide on a scale only seen before in Kampuchea, I still get diesel bug. But knowing that, I can deal with it, most of the time. The other important facts are that I refill my 2.5 gallon fuel tank between 5 and 10 times in a season, and the "plastic can" reserve of 4 gallons is dead easy to top-up on the way to/from the boat.

Dave
 
I don't know about engines themselves though, as you say, it's likely to be the latest and turbo engines that matter most. I know people who think road fuel has an advantage for boat heaters of the Epersbacher/Webasto type. I've had to use whatever comes to hand on my 8 yr old Volvo as I don't feel like lugging 100 litres around in cans.
 
Horses for courses. If you have a technically demanding (high speed, modern) engine with a clever electronic brain and a sophisticated injection sytem, then it will work better, live longer, with an advanced fuel.

Clever fuels are wasted on e.g. ancient Listers, and tonka-tonkas.

Some reading: BP highperformance diesel


I guess that there will be gradual changes to legislation to make all diesel engines perform better and with less harmful emissions. Quality diesel fuel is only one way of achieving improvements: fuel spec improvement, better filtration in the input lines, exhaust gas catalysers, etc, etc.

It's not unreasonable to expect that the owners of really old smokey engines will be targetted to change to cleaner engines. In California (where else !) subsidies are available to owners of smoky old trucks, to change to cleaner more efficient ones.
 
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Clever fuels are wasted on e.g. ancient Listers, and tonka-tonkas.

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Accepted that the higher fuel specification is not required, but do you know if burning road fuel could do an older / basic spec marine diesel any harm?

After November this will become very relevant since red from a marina is likely to be a dearer than diesel from a garage.
 
There is a guy who posts (in fact he is an adminstrator) on the Small Boat Club forum under the name of NigeL who is a real expert on these matters, owning as he does a fuel testing laboratory. He used to post here using various user IDs over the years but no longer does. All his past posts still exist which you might be able to find despite the current naff search arrangements.

Unfortunately you'll have to downsize considerably to qualify for membership of the Small Boat Club /forums/images/graemlins/smile.gif
 
No need to buy the very best quality grades, then. Stick to ordinary white ones. They should have better lubricity and detergent qualities than ordinary old red marine diesel, so the engine may "improve" after a while.

If you only need small quantities, there are some garages in rural areas which serve red for agricultural or industrial machines. Or make Friends with a Farmer !
 
The issue is that high sulphur (i.e red diesel) content aids with the lube of the injection pump, so something like a Perkins 4107 from 1950 something probably won't do so well on low sulphur road fuel
 
Thanks for the link - I wondered where Nigel had gone. I've registered (or started the process - approval can take a day or two, apparently), and posted my query as a guest meanwhile. I see that a number of weel kent posters from here contribute.
 
I would have thought using marine diesel from a good source with a large throughput of fuel would ensure reaonable quality of diesel. Combined with regular changing of fuel filters, I have had no engine problems due to contaminated fuel. And of course good external filtering of everything going into the tank is essential.
 
hi here we just got road d.. never had anything different my volvo been running on it since new 15 to 20 years now may evern be longer , as it was in boat when i got it ,, its done thousands of miles , no s... in tank ever, no break downs , never seviced by a mec in my ownership . so use r,... d ...its fine dave, should think its same as we got /forums/images/graemlins/confused.gif /forums/images/graemlins/confused.gif yes
 
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