With this configuration, the connection from the diesel filter (shared) will also need to be blocked off, as the veggie would return to the diesel tank when veggie is selected. The fuel pump will pump veggie as well as it pumps diesel. I am using the fuel pump for 'veggie only' in one car and both fuels in the other car I have here. I is not so much "which configuration is best for the car?" as "which conversion you are happy with using." I will try to list the advantages and disavantages of each configuration below:
Configuration #1 - Fuel selection valve before the stock fuel pump, both fuels share the diesel filter, air bleed from diesel filter disabled, looped return on veggie, return to tank for diesel.

• Easy to install, no added fuel pump needed.
• Long purge time due to amount of fuel in the shared filter. This also sends veggie to the diesel tank and may affect cold starting after a while.
• Bleeding of fuel system after diesel fuel filter changes is more difficult than unconverted engine.

Configuration #2 - Fuel selection valve before the stock fuel pump, relocate the diesel filter to before the fuel selection valve, air bleed from diesel filter disabled, looped return on veggie, return to tank for diesel.

• Requires more modifications to fuel system than #1.
• Shorter purge time due to no shared filter. Significant reduction in amount of veggie sent to the diesel tank.
• Bleeding of fuel system after diesel fuel filter changes is more difficult than unconverted engine.

Configuration #3 - Separate fuel pumps for diesel (new electric fuel pump) and veggie (stock fuel pump), fuel selection valve between filters and IP inlet, return line returned to appropriate tank for the fuel used, diesel filter air bleed not blocked, air bleed could be provided for veggie filter (to veggie tank return line if fitted).

• Requires added fuel pump and some re-arrangement of plumbing to allow fuel pump for veggie use only.
• Shorter purge time due to no shared filter. Significant reduction in amount of veggie sent to the diesel tank.
• Bleeding of fuel system after diesel fuel filter changes is easier than in unconverted engine (electric pump for priming diesel side).

I hope that my comments above have helped.
Tony

Tony,

Thanks for taking the time to explain things for me. I think configuration #2 is what I can go by for now. and maybe later I can add an extra pump.

Where to buy that extra pump do you know?

When you said ...

Bleeding of fuel system after diesel fuel filter changes is more difficult than unconverted engine.

Did you mean that it will take longer to bleed, going to be too hard. Could you please explain why?

Thanks Tony

Regards,

Fitian

I have bought small electric fuel pumps on eBay for around $25 - $40 ea. They need to be able to pump diesel, so in general, the Facet bran or similar should be fine. The fuel filter is on the suction side of the fuel pump. The air bleed is blocked. You will need to open the fuel piping somewhere after the fuel pump or loosen the fuel pipe going into the IP, so that the air from the new (empty) filter can be pushed out of the fuel system and be replaced by fuel.

Hello Tony,

In regards to the Banjo Bolt. Do I block it only from the bottom or do I also block the three holes please?

Thanks

Fitian

Fitian, you want the return lines to work and so route the fuel back to the Pollak valve (or to the tank etc), so you have to block the bottom of the bolt only. I used metal epoxy.

If you block all the holes of the banjo bolt you will have a nice mess to clean up when the return lines burst

__________________
Cheers
Bruce
http://oztayls.blogspot.com/

1976 W123 300D (3 litre 5-cyl NA diesel running on SVO since June 2006)
1982 W126 280SE (Sadly is For Sale)
1993 W124 300D (3 litre 6-cyl NA diesel - being converted to SVO)

Yeah , I am so thankfull for your advise Bruce. I blocked only the bottom and tried the system before I posted the question. But I wanted to make sure I understood everything the right way.

I have followed the same steps you took to build the system. So I am using separate filters and one lift pump.

I have just finished wiring up the Pollak valve today and checked all the lines then (let me use your words) "I threw in the good stuff " and went for a drive. Man it is a great feeling indeed.

I must Thank you Bruce for your posts, pictures and diagrams. That was a great help.

I must also thank you Tony the true WIZ of OZ for all the support, photos and advises. Thank you for being so patient with me and my ignorance . Sorry if I gave you hard time.

I'll post some photos of the final situation soon.

Best regards,

Fitian

Good work Fitian! You have done well and get full marks for persistance and getting your conversion completed

__________________
Cheers
Bruce
http://oztayls.blogspot.com/

1976 W123 300D (3 litre 5-cyl NA diesel running on SVO since June 2006)
1982 W126 280SE (Sadly is For Sale)
1993 W124 300D (3 litre 6-cyl NA diesel - being converted to SVO)

Thank you Bruce,

I would not have done it with you and Tony.

Here are some final photos...



Also the Lift Pump ...



And the switch...



I still have to buy a good fuel tank (where did you get yours Bruce?) . I am using a 25 ltr jerry can for now.

I'll post a photo of that later.

Regards,

Fitian

Fitian

I bought my plastic tanks from a marine supplyer on eBay. But I see K-Mart now stocks them as well! Otherwise, in Newcastle, either Bulbecks at Islington, or the one on Hunter Street West. I can't remember the name.

Excellent pics!!!

__________________
Cheers
Bruce
http://oztayls.blogspot.com/

1976 W123 300D (3 litre 5-cyl NA diesel running on SVO since June 2006)
1982 W126 280SE (Sadly is For Sale)
1993 W124 300D (3 litre 6-cyl NA diesel - being converted to SVO)

Fitian,
Great Pix, excellent work, did you manage to get an on/on switch or did you have to settle for an on/off/on switch?