- Jun 5, 2020
- 46
- 52
- Funster No
- 71,456
- MH
- Elddis Accordo 135
- Exp
- Since 2017
Well I did what everyone always says, and filled the tank up end of summer (beginning of Sep) a couple of years ago.
Then, end of November, a bit frosty, went to take the motorhome back to the dealer for something, but a few miles down the road the eml warning light came on.
The strange symptoms were - foot off the accelerator, warning light off, touch the accelerator, light comes on.
The Peugeot garage helpfully replaced the fuel filter, cleaned the fuel lines, relieved me of £78.48, and told me I'd been using too much supermarket diesel.
This struck me as odd - AFAIK there's no difference - so I looked into a bit - my conclusion is it's probably a bio-diesel problem.
What I found was Bio-diesel:
- has about 90% energy density so fuel consumption's a little higher
- can affect low temp operation, eg rapeseed oil is liquid at 0°C but palm oil solid
- short trips can be a problem as wax in filter doesn't melt (longer journeys allow warm fuel to melt any wax)
Two things (to save you googling them) that keep coming up are:
- the Cold Filter Plugging Point (CFPP) is the lowest temp at which biodiesel flows through a filter, and
- the Cloud Point, the temp at which solid wax particles form, clogging filters and injectors
For mineral diesel the CFPP is -14 to -7°C; for bio-diesel it can be as high as +1°C
Then I found there are two sorts of diesel supplied from pumps, specd in En590, "summer" and "winter" diesel.
In the UK our specs are:
Summer (16.Mar-15.Nov) CFPP is -5°C and Cloud Point is +3°C
Winter (16.Nov-15.Mar) CFPP is -15°C and Cloud Point is -5°C
In addition, apparently most modern diesel vehicles have a fuel filter heater to allow summer diesel to be used down to -20°C - but I suspect the diesel wasn't getting as far as the heater. I think I read somewhere that excess fuel is fed back to the tank, so eventually the tank will be warmed, but it could be a long 'eventually'?
When I asked Peugeot, they confirmed that my 2017 Boxer base does have a fuel filter heater, and, no, diesel additives aren't recommended.
I checked BP, who said "we supply fuel appropriate to the season. Summer fuel should not be kept for winter use."
And my nearest local, Sainsbury, who said "winter diesel is distributed from Sep onwards."
So my conclusions were:
- yes, fill to the brim over winter to reduce microbial growth
- but wait til October to do it!
- see if you've got a fuel filter heater
- and do a fast motorway run every now and then anyway.
But, am I right?! I've mentioned it to a few people and no-one seems to have heard of this summer/winter thing - and my kids keep telling me I don't know anything anyway...!
Then, end of November, a bit frosty, went to take the motorhome back to the dealer for something, but a few miles down the road the eml warning light came on.
The strange symptoms were - foot off the accelerator, warning light off, touch the accelerator, light comes on.
The Peugeot garage helpfully replaced the fuel filter, cleaned the fuel lines, relieved me of £78.48, and told me I'd been using too much supermarket diesel.
This struck me as odd - AFAIK there's no difference - so I looked into a bit - my conclusion is it's probably a bio-diesel problem.
What I found was Bio-diesel:
- has about 90% energy density so fuel consumption's a little higher
- can affect low temp operation, eg rapeseed oil is liquid at 0°C but palm oil solid
- short trips can be a problem as wax in filter doesn't melt (longer journeys allow warm fuel to melt any wax)
Two things (to save you googling them) that keep coming up are:
- the Cold Filter Plugging Point (CFPP) is the lowest temp at which biodiesel flows through a filter, and
- the Cloud Point, the temp at which solid wax particles form, clogging filters and injectors
For mineral diesel the CFPP is -14 to -7°C; for bio-diesel it can be as high as +1°C
Then I found there are two sorts of diesel supplied from pumps, specd in En590, "summer" and "winter" diesel.
In the UK our specs are:
Summer (16.Mar-15.Nov) CFPP is -5°C and Cloud Point is +3°C
Winter (16.Nov-15.Mar) CFPP is -15°C and Cloud Point is -5°C
In addition, apparently most modern diesel vehicles have a fuel filter heater to allow summer diesel to be used down to -20°C - but I suspect the diesel wasn't getting as far as the heater. I think I read somewhere that excess fuel is fed back to the tank, so eventually the tank will be warmed, but it could be a long 'eventually'?
When I asked Peugeot, they confirmed that my 2017 Boxer base does have a fuel filter heater, and, no, diesel additives aren't recommended.
I checked BP, who said "we supply fuel appropriate to the season. Summer fuel should not be kept for winter use."
And my nearest local, Sainsbury, who said "winter diesel is distributed from Sep onwards."
So my conclusions were:
- yes, fill to the brim over winter to reduce microbial growth
- but wait til October to do it!
- see if you've got a fuel filter heater
- and do a fast motorway run every now and then anyway.
But, am I right?! I've mentioned it to a few people and no-one seems to have heard of this summer/winter thing - and my kids keep telling me I don't know anything anyway...!
).
