Darkened red diesel

N

NormanS

Well-Known Member
Joined
10 Nov 2008
Messages
10,042
Visit site
In common with many other boat owners, I filled up my boat's tanks last Autumn. I haven't launched this year, and was aboard for the first time last week, since "lockdown" last March. I sampled the fuel from both tanks, and found that although clean, and no sign of water, the fuel was significantly darker than normal. I know that this is not unexpected with old fuel, and is a sign of oxidising, but it will be at least a further six months before launching. What treatment, if any, would the knowledgeable on here suggest? It's about 450 litres, and is good old high sulfur fuel, and has had no treatment or additives so far.
 
NormanS said:
In common with many other boat owners, I filled up my boat's tanks last Autumn. ........It's about 450 litres, and is good old high sulfur fuel, and has had no treatment or additives so far.
Click to expand...

I thought we had been using ULS fuel in the UK for about a decade?
Anyway a dose of fuel treatment cant possibly do any harm.
.
 
MartynG said:
I thought we had been using ULS fuel in the UK for about a decade?
Anyway a dose of fuel treatment cant possibly do any harm.
.
Click to expand...
+1. Many of use hold year old fuel in our tanks, even older...You have to have more reason to ditch it than you have described.

You could check out your primary filter(s) and see if anything's festering in the inspection bowl. If so, oh dear...most likely nothing to report, so...

You can dose it, and run one engine for a while to see if all is well - it will be, But don't go far out to sea if still in doubt. A further check on the primary filter will assure you

PWG
 
I use Soltron, now sold as 'Startron' it is not a biocide just an enzyme but it is claimed to extend the storage life of fuel. It would do no harm to try it. If you fuel looks clean why would darkening of the dye be a problem?
 
One of the reasons I moved to white was I could remove the fuel from the boat if it was not being used and fill the car up.

It is currently suggested that modern diesel has a shelf life of six months. I follow that advice after having a dose of the bug with red a few years back and strongly suspect it had been sat in a tank for months.
 
If it's dark but not cloudy, it may be some sort of asphaltene-ish 'tarry black shit' dissolved rather than anything biological?
I wonder if an additive like Miller's would be useful to avoid deposits in the injectors or whatever?
TBH I'm skeptical about all these snake oils, but an enquiry or two to the makers' help desks might be worthwhile?

Why do people have this urge to hoard red diesel? It's not red wine chaps, it doesn't improve with age!
 
Sandy said:
It is currently suggested that modern diesel has a shelf life of six months. I follow that advice after having a dose of the bug with red a few years back and strongly suspect it had been sat in a tank for months.
Click to expand...

I expect Covid has reduced many peoples boating activities this year so old fuel in boat fuel tanks may be quite common. I have avoided putting too much fuel in this year and have topped up with two relatively modest 100 litres each time (motorboat) . Some of last years fuel may in theory remain but should have become well mixed with this years fresh fuel.
I do use fuel additive and will put an extra dose in prior to the winter . I think the fuel is okay more than a few months and certainly some people only refuel once year but don't seem to have any issues.
 
MartynG said:
I thought we had been using ULS fuel in the UK for about a decade?
Anyway a dose of fuel treatment cant possibly do any harm.
.
Click to expand...
My supplier also supplies several of Calmac ferries. That's why it's still high sulfur. Good for the engine, very bad for Eberspacher.
 
TernVI said:
If it's dark but not cloudy, it may be some sort of asphaltene-ish 'tarry black shit' dissolved rather than anything biological?
I wonder if an additive like Miller's would be useful to avoid deposits in the injectors or whatever?
TBH I'm skeptical about all these snake oils, but an enquiry or two to the makers' help desks might be worthwhile?

Why do people have this urge to hoard red diesel? It's not red wine chaps, it doesn't improve with age!
Click to expand...
It is common practice with boats, to keep fuel tanks full over the winter. Many including me believe that it prevents condensation.
 
Quandary said:
I use Soltron, now sold as 'Startron' it is not a biocide just an enzyme but it is claimed to extend the storage life of fuel. It would do no harm to try it. If you fuel looks clean why would darkening of the dye be a problem?
Click to expand...
Thanks, that sounds promising.
 
I've used Marine 16 now for several years after getting a dose of diesel bug. Two versions available - complete and maintenance. Not had a problem since but I do fill up with white diesel.
 
NormanS said:
It is common practice with boats, to keep fuel tanks full over the winter. Many including me believe that it prevents condensation.
Click to expand...
Fools asking for trouble in my opinion. Your lack of condensation is probably not much comfort now.
 
My tanks were half full last winter and no fuel issues this year as far as I know and have consumed about 200 litres.
These days I am less inclined to leave a the tanks full over winter as the probable biofuel content of diesel is a concern regarding fuel storage life.
I did use Marine 16 but changed two years ago and I am presently using Clearwinner LA88 fuel additive. I think additives probably do help with smooth running but cant really offer any proof of that. Lack of any fuel issues doesn't necessarily prove anything.
Clearwinner Fuel Additive Technolology | Marine
.
 
I have had same issue in the past with good old sulphur fuel.
I use Marine 16 complete.
I used the very dark fuel with no ill effects. I checked the fuel filters and found nothing in them.
Still use FAME free fuel when I'm in the UK. When we go abroad (France) and have to use white diesel with FAME in it I make sure to run it out asap.
Fair winds
 
Soltron was developed in the Engineering Department at Queens University in Belfast, (Prof. Blair,) they did some interesting things there at that time including building a road racing motorbike from scratch with an innovative engine they built in their workshop, the technician who worked there got to ride it and was quite successful for a few years which indicated to me that they knew what they were about.
 
Quandary said:
Soltron was developed in the Engineering Department at Queens University in Belfast, (Prof. Blair,) they did some interesting things there at that time including building a road racing motorbike from scratch with an innovative engine they built in their workshop, the technician who worked there got to ride it and was quite successful for a few years which indicated to me that they knew what they were about.
Click to expand...
Because anyone who designs a motorbike is obviously the best at organic chemistry?
 
JumbleDuck said:
I imagine MAIB will tell us. My guess is that it's for much the same reason that preserved steam locomotives keep breaking down in traffic and preserved aircraft keep crashing; there just aren't the opportunities to achieve and maintain currency in operation or maintenance of old machinery.
Click to expand...
TernVI said:
Because anyone who designs a motorbike is obviously the best at organic chemistry?
Click to expand...
I clearly understood the post , if you read it again you will see the motorbike part was completely separate from a professor of engineering working out a good diesel additive , but goodness me what do these engineers know from a university renowned for their engineering prowess . I know let's ask the forum instead , by jings I think I've cracked it no ref . To jumbleduck sorry my error and I canny seem to delete it
 
I’ve used over 1000l so far this year and, having suffered a dose of the bug, I’ll run the tank as low as I dare before lift out and then empty and clean the tank. Next year the tanks will either be brimmed or emptied again for the winter, if empty then ‘hoovered’ out before relaunch to remove the inevitable water from condensation. Suggest the OP puts a double dose of Marine 16 in the tank then puts some serious hours on the engine next year (y)
 
You must log in or register to reply here.

Share this page

Top