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I love my 2002 Outback but it drinks too much petrol around town. I was thinking of buying a new boxer diesel engine (or obtaining one from a wreckers if one were available) and swapping it for my 2.5 litre petrol engine. Does anyone know if the boxer engine will run on biodiesel made from cooking oil? I've found a supplier of biodiesel in my area that sells it for $1 per litre and it appears a good way to save money and the environment. Thanks.

drinks to much you say?? as in how much? you should be seeing at least 400-450 ks out of 55ltrs around town and 600 on the hiway!!

bryan

Thinking,how much would Subaru charge for a new engine,you better have a ticket in Oz7 tonight.

Hi Mate,
There is a warning sticker on the inside of the filler cover on my Outback Diesel - Clearly saying DO NOT USE BIO DIESEL.

I am told that the quality of Bio can be variable and that it doesnt always burn as clean as Crude derived Diesel. Leaving deposits and residue inside the engine.

Also given that the Scoob engine is running a high pressure injection set up... the Bio is said not to work well in this modern kind of design.

Older (lower injection pressure) engines seem to agree better with bio diesel.
Hope this helps.......but do recommend you try a scoob diesel - they are excellent.

Cheers
Giles.

I'd advise talking to the Biodiesel place, they would likely be the most knowledgeable on the suitability for different vehicles. The sticker is likely "playing it safe" as quality of Biodiesel can naturally vary heaps - especially with it becoming more common for people to run their own backyard distilleries.
I used to do the IT for one of the first Biodiesel companies in Perth who were doing most of the pioneering for developing mobile Biodiesel factories and they reckoned the end product was better in every single way than anything you'd get from a servo pump.

*note - the above is about the entire extent of my knowledge of all things diesel!

i would not be using biodiesel in a subaru...................(full stop)

while im sure there is no problem with biodeisel being almost exactly the same i just wouldnt risk it.
if it was in an older vehicle then i would be happy but id run it on homebrew. considered i could buy a new engine for a carton down the wreckers.

a few things when running bio-desiel, lower pressure-higher boost than normal.

Those concerns would have merit if you were intending to put homemade stuff into your car.
I don't see what they could be based on if using properly refined stuff from a reputable supplier.

As mentioned, you are "sure there is nothing wrong with it", yet you still never use it "full stop" - irrational much??

AndrewT wrote:
As mentioned, you are "sure there is nothing wrong with it", yet you still never use it "full stop" - irrational much??

im very irrational
there is no "industrial" process for biodesiel its all very simple chemisty just on larger scales.

It seemed pretty high tech from what I saw a few years back and they were super confident in it. I'm sure the technology has progressed a fair way since then too. Naturally you'd want to be sure first before trusting your Subaru's health to it but yeah, I like to keep an open mind for this kind of thing.

you can create somthing high tech from somthing very simple.
a small idea of how its done.
filter
add lime (alkaline) to drop heavy metals
i do belive theres another proccess involving glycerene to make it more viscous but yeah thats about it

The industrial process is far more complex & yields a much superior product - the crude oil (after filtration, removal of water & acid) is reacted with an alkoxide (typically sodium methoxide) , glycerine removed (as it should not be in final product) with the resultant product being the methyl ester of the original oil's fatty acid (eg methyl tallowate if the starting "oil" was tallow) . Done properly this produces a high quality biodiesel suitable for modern engines.

First of all I'd be looking at the conversion issue before you even begin looking at the biodiesel question!

As mentioned, how much are subaru going to charge for a new donk, let alone an ECU and wiring loom - then there's the security measures to get around. Its not as easy as bypassing things these days. The ECU references many of the components in the wiring loom, if those are missing the ECU will not operate properly.

This is what I've been lead to believe anyway. The more modern wiring looms are becoming very sophisticated and until some one finds a proven way to cut down a loom to make it work I'd reckon it'll be very hit and miss + a lot of money to get it sorted. And I doubt Subaru will supply a wiring loom that will "just work" in your older subaru...

Cheers

Bennie

the main reason subaru says not to run the boxer diesel on bio-diesel is the octane rating of bio-diesel, it can vary from 80 - 90 ron where crude derived diesel runs 90 ron and above

and making bio-diesel is a little more complicated than most people think

http://www.dangerouslaboratories.org/biodiesel.html

http://www.make-biodiesel.org/

TOONGA

TOONGA wrote:the main reason subaru says not to run the boxer diesel on bio-diesel is the octane rating of bio-diesel, it can vary from 80 - 90 ron where crude derived diesel runs 90 ron and above

and making bio-diesel is a little more complicated than most people think

http://www.dangerouslaboratories.org/biodiesel.html

http://www.make-biodiesel.org/

TOONGA

Yep gotta agree with you there Toogs. That backs up what I have been told. The variables for bio are wide as a footy pitch.
You get the conceintious and the cowboys, how do you tell who is doing a good job of it (and i am sure some will be) and how do you tell whos not?
When your Boxer Diesel Donk (love that name) goes kerplunk due to out of spec fuel then where do you turn? Deffo not worth the risk......just yet anyway.
If say Shell or similar produced the stuff to an accepted industry standard then I am sure the motor manufacturers would begin to accept the stuff.

Hey ho in the meantime we can all look forward to being ripped off at the pumps - here is the current cost of Diesel here its £1.279 per litre. Thats for BP ultimate (higher octane) the standard will be a bit cheaper.
Whats the cost in OZ land?
That's all folks!
Giles.

$1.32 here at the moment.Only one type available.

Have you thought about getting to the bottom of why your petrol engine drinks too much ? Does it have some kind of mechanical/electrical problem or possibly driving habits ?

I wouldn't have thought that converting from petrol to diesel is economically feasible .

A .

some sort of bio Diesel powered vehicles used to end up being towed into the yard, or just out the front of a local Diesel specialist. Mainly older clunkers, but always got a chuckle from the specialist - more work , but same could be said for many others that ran fuel company Diesel, given good service life , and sometimes not. New Diesel fuels make old seals leak like an old woman!

mate, dont use bio-diesel!!! it is the biggest, Shittest fuel on the market, it will ruin your engine. i have had a couple of my mates do it to there cars. and it also takes away alot of the little power you get out of a deisel motor.

Cheers Mike

Here a couple 2-3 years ago they built the largest bio diesel plant in the US, at a neighbooring city some 20 miles away. A few months back one of its 1 million gallon holding tanks blew up...woke up that town:shock: Diesel has looked good compared with gas here for some time and you get some pretty good tax credits etc for buying a diesel vehicle. All ive heard on changing to bio is compatible rubber fuel lines if so equipped and wasnt aware of the varying ron ratings, doesnt sound like a good idea

Im not sure how available lpg is around tassie but these sytems look interesting if you dont mind your car to being a gunnie pig.
http://www.gastek.com.au/cgi-bin/engine ... ml&Rec=156
More power, sligtly better economy (depending on the price of lpg) and more range.