I know how to drive and can do a bit of DIY , but this forum will take some learnin!
I've just got a Merc 300D and can't wait to stop burning fossil fuel.
Is there anyone else out there with one and maybe a bit of advice?
I believe I should be replacing any rubber hoses with plastic or otherwise and putting in an extra little filter or two.
Good to hear that Linfox is going to be using bio I think, from a plant that will be built in Melb.

Daved

Welcome.

Firstly! Don't worry about your hose's JUST yet they won't be an instant problem. The main issue is to keep an eye on them to make sure that they are in good condition. You should normally do this for any type of fuel line even on normal diesel use. You don't want fuel going to places it shouldn't be When they get soft and or weep then you need to change them and from what I understand (I have a new car so I am not effected by this challange) the return line will be the one to show the first signs of problems as the biodiesel sits in these lines a lot longer and don't travel as fast therefor giving the bio more time to react with the material they are made from.

Secondly! Some people like to install cheaper CAV filters before the standard filter to reduce costs when it comes to runing Biodiesel for the first few times after running lots of dinodiesel. Depending on how the fuel gets to the IP and I don't personally know the 300D, you can either add a CAV filter before your normal filter or you could replace your normal filter with a CAV filter. The reason you have to be carefull you don't want to stress your IP if it is getting the fuel from the tank. If there is another pump just pumping fuel then you might be OK. Wait for some of the oters who know 300D's so they can give you their advice and what they have done to their cars.

Glad you could join us and don't be affraid of the forums they grow on you after a while and this place is a great source of information for all don't forget what you learn you can pass on to others so they will learn, never stop learning.

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Dave

Daved,
In our household we have 3, 300Ds. I have maintained them myself and have even removed and reinstalled the engines in a couple of them.

The normal diesel fuel system for the 300D is that in the bottom of tank, there is a nylon? screen which prevents large particles entering the fule lines. The fuel suction line is screwed into the base of the screen and connects to the steel fuel line going to the engine bay via a nitrile rubber fuel hose.
In the engine bay the metal fuel line connects to an in-line filter via a nitrile rubber fuel hose. The in-line filter connects to the fuel pump (with primer pump to bleed air out in case of filter changes or lack of fuel). The fuel pump connects via a rigid plastic hose to the main fuel filter.
At the top of this filter is a 'banjo bolt' which allows air to bleed from the filter and also connects the IP return line and the injector return line to the return line to the fuel tank.
The injectors have return ports which are connected together, using nitrile rubber hose, from one to another. The front injector connects this series line of injector return ports to the banjo fitting on the fuel filter. The rear most injector has one return port fitted with a blocked nitrile rubber hose, to seal off that port.
The injector pump has a return port (located on the engine side of the IP), which has an integral pressure relief valve fitted. This ensures that the fuel gallery in the IP is at a positive pressure and still allows fuel to be returned to the banjo fitting on the fuel filter.
A shaped nitrile rubber hose (cigar hose) connects the banjo fitting to the steel return fuel line.
At the underside of the fuel tank a short piece of nitrile rubber hose connects the fuel line from the engine bay to the return line into the tank.

When first using biodiesel (at >B20 blend ratio), I advise adding an additional, cheap fuel filter before the Mercedes filter at the fuel pump. Additional spare filters should be carried, alonf with the tools to replace the filter on the roadside. These filters can be bought for as little as $2.00 each, so it is not a financial burden to replace a few of these while using the first few tanks of biodiesel.

I do not recommend changing the fuel filter for a CAV style fuel filter.

If you were to decide to convert your 300D to use unconverted vegetable oils, I would recommend adding a CAV filter as well as an additional, heated fuel system for the vegetable oil fuel.

Tony, what brand? what reseller?

Great ! Thanks for the welcome Jacka and the info ,no need to panic. I like your logo , no war required...Hopefully use of Bio fueland other alternatives will ween more people off the chronic addiction to fossil oil and have some impact,... someday.
There's a good mag on renewable energy called Renew ,from the Alternative Technology Association.
And fantastic detailed info on my fuel system Tony , thanks a lot. I was a bit lost but now is all clear. Is Nitrile rubber something other than just natural rubber which will last longer?

I get thenm from the cheapest junkiest car parts place across Australia (who seem to devote more retail space to junk than parts). I can get them for around $1.75 at MALZ in Cannington WA.

Daved,
Nitrile Rubber is standard fuel hose. Natural Rubber is not used in fuel systems as it dissolves in petrol and diesel

Tony,

Thanks for the filter info.

I picked up this piece of info about Nitrile rubber from the Biodiesel Handling and Use Guide distributed by the DOE
"Nitrile rubber compounds, polypropylene, polyvinyl and Tygon materials are particularly vulnerable to B100."

By the way, this is the first reference I've seen to polypropylene being a problem. I'd bought a 200 litre drum for washing and storage.

George

Tony from west oz, so in your experience when you started using bio in your 300's, you just put in the supp. filter until the tank was clean and had no other problems for a while?
And why the "UFO" shaped tubing to the return line from the standard filter.

Also anyone who could please help me with my basic misunderstanding of the cycle of the diesel and why it doesn't have the vacuum of a petrol
Much appreciated
"we get there eventually in the 300D"

Hi Daved

I assume you are reffer to manifold vacuum, and any non turbo engine will have manifold vacuum.

Thanks
NewBioer