Changing the liquid fuel in a bottle

[bren73]

I have just got my first liquid fuel stove, an Optimus Polaris Optifuel, and I was wondering about how to go about changing the fuel type in the bottle. I can’t seem to find any info about this anywhere.

At the moment I have it full of paraffin, but I would like to change over to something like Aspen 4 at some point.

My question is…once the paraffin has run out, do I just fill it up with different fuel or do I have to somehow flush the residue of the paraffin out the bottle first before I fill it up with the new fuel?

 

[Ystranc]

Optimus Polaris Optifuel Manual (Page 12 of 18) | ManualsLib

www.manualslib.com

The relevant bit is on page 12, “you shouldn’t mix fuels in the bottle” is as far as you need to take this. Some fuels such as petrol/ diesel are really not compatible with each other.

 

[bren73]

Yeah, I’m not planning on mixing fuels, it was more a question of how clean the bottle needs to be when I change the fuel type over. The manual only states “Empty the bottle entirely before putting in a different fuel.”

 

[Ystranc]

Yup, that’s All.

 

[Broch]

The very small amount of fuel left after you've emptied it will not affect the performance of the new fuel at all - it will make up a very, very, small percentage of the mix. If you had 5ml left in a 500ml bottle it would be 1% and I doubt you'd leave as much as that in.

If you incorrectly fill your diesel tank with petrol you just empty it and fill it back up - no flushing.

 

[bren73]

The very small amount of fuel left after you've emptied it will not affect the performance of the new fuel at all - it will make up a very, very, small percentage of the mix. If you had 5ml left in a 500ml bottle it would be 1% and I doubt you'd leave as much as that in.

If you incorrectly fill your diesel tank with petrol you just empty it and fill it back up - no flushing.

Thanks Broch, that’s what I was hoping it would be

 

[demographic]

In the manual for my old smilie face Transit van it actually recommended adding a a small percentage of petrol to the diesel for winter use as it stopped the diesel from gelling.

I can't remember the exact amount now as I never did it.

I can't see the residual amount left in a bottle clinging to the sides making any difference to the stoves performance.
Changing from a water based fuel like alcohol to a petrochemical one however might be more of an issue.

 

[sidpost]

Be careful mixing gasoline with diesel. It may be the poorman's #1 diesel but, if you don't know what you are doing, don't do it! A little too much will do damage to the motor before you know it that will cost you huge money to fix.

I can't speak to the UK but, if I need #1 diesel to stop gelling, that will generally be the only fuel type at the pumps I use.

 

[sidpost]

My question is…once the paraffin has run out, do I just fill it up with different fuel or do I have to somehow flush the residue of the paraffin out the bottle first before I fill it up with the new fuel?

If you want to be extra careful, once your bottle is 'empty', add a a couple ounces or few ml's of you new fuel and 'swirl' it in the bottle and dump it out. At that point, your old residual fuel type is going to be < 0.1%, likely a whole lot less so, you are safe for whatever fuel transition you want to make.

Personally, I don't stress about it and generally just 'shake it empty' and put the new fuel in go on my way. Something like diesel to alcohol would get a little more attention but, I don't run alcohol in a 600/750/1000ml bottle as a fuel type.

Some good Bourbon is a different topic!