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This system lets me use straight vegtable oil in (almost) any temperatures without fear of wrecking my engine, it also to a certain extent will work on any diesel engine (I've seen similar systems on T5 174's).



I have a seccond fuel tank (a marine outbord one) inside the van with it's own fuel pump (ex Jag xjs)



Which pumps the veg oil through a heat exchanger (blue) and heated filter (red) being heated by the van's cooling system



The veg oil through a one way valve (blue) back to the tank. Starting on diesel as normal. Once you are moving and the pump is active things start heating up.

Once the engine is up to normal operating temperature, the throw of a switch and the 6 port 2 way valve (red) swaps from running dino diesel to heated veg oil.



A mile or so before stopping I switch back to regular diesel but also switch on the 3 way 2 port valve (yellow) so the return line heads to the veg oil tank not the main tank to avoid contaminating it with veg oil.

The swiches in mine are just some rocker switches in the dash



There are plent of more complex systems out there, with automatic systems to stop you swaping fuels at the wrong time. There is also a lot of info on the web about systems like mine and many other variations. I though I'd put this up here as I couldn't find much info on systems fited to T4's

I 'm lucky enough to have access to used veg oil from a couple of sources thus making this conversion financialy a good idea - It's a bit mesy collecting and filtering but any longer journey is mostly free ;). It also gives much lower emissions (when tested on veg)
 

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This system lets me use straight vegtable oil in (almost) any temperatures without fear of wrecking my engine, it also to a certain extent will work on any diesel engine (I've seen similar systems on T5 174's).



I have a seccond fuel tank (a marine outbord one) inside the van with it's own fuel pump (ex Jag xjs)



Which pumps the veg oil through a heat exchanger (blue) and heated filter (red) being heated by the van's cooling system



The veg oil through a one way valve (blue) back to the tank. Starting on diesel as normal. Once you are moving and the pump is active things start heating up.

Once the engine is up to normal operating temperature, the throw of a switch and the 6 port 2 way valve (red) swaps from running dino diesel to heated veg oil.



A mile or so before stopping I switch back to regular diesel but also switch on the 3 way 2 port valve (yellow) so the return line heads to the veg oil tank not the main tank to avoid contaminating it with veg oil.

The swiches in mine are just some rocker switches in the dash



There are plent of more complex systems out there, with automatic systems to stop you swaping fuels at the wrong time. There is also a lot of info on the web about systems like mine and many other variations. I though I'd put this up here as I couldn't find much info on systems fited to T4's

I 'm lucky enough to have access to used veg oil from a couple of sources thus making this conversion financialy a good idea - It's a bit mesy collecting and filtering but any longer journey is mostly free ;). It also gives much lower emissions (when tested on veg)
,,,,good on ya mateT: saves paying gordon the moron your hard earned
 

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Hi, I put a twin tank set up on my t4. Veg oil in the main tank and fitted a mini motor tank under the bonnet for the diesel. The problem I'm having is the diesel is soon running out of the small tank (a lot faster than expected). I can only think that it's returning it to the main tank. So my question is how do I sort this problem ? Thanks in advance
 

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Is a second tank safe in the engine bay? Aren't cars normally designed to have fuel tanks not in crumple zones? Out of interest, what size is the tank?

To help, I think that yes it's returning to the main tank, but that's correct because otherwise you may get veg oil in your diesel (second) tank which will cause start up problems.
 

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looks good. I'm half way doing this myself. Very similar setup as yours but i've used a cak water tank fitted under the van to be used as the veg oil tank.

I've not added a second veg oil pump. But that does look like a good idea as the oil is thicker and should put less strain on the injector pump. How did you decide on the jag pump? is there any risk of over pressurising the injector pump.

snowman0: you will need to make sure the return fuel line goes back the to right tank ( there are two return pipes, one of injectors and one off injector pump )
 

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I don't run a twin tank , I had the injection pump rebuilt to veg oil spec by Diesel Bob Tuning £250 and run 100% veg oil all year round T:

£12.99 per 20 litres at the moment ;)
 

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do you run any extra inline heaters or pumps?

Assume the pump rebuild is just replacing the seals for veg oil safe ones?
 

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do you run any extra inline heaters or pumps?

Assume the pump rebuild is just replacing the seals for veg oil safe ones?
The pump is rebuilt using Viton Seals , I have a Heat Exchanger and a Facet Lift pump T:
 

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I don't run a twin tank , I had the injection pump rebuilt to veg oil spec by Diesel Bob Tuning £250 and run 100% veg oil all year round T:

£12.99 per 20 litres at the moment ;)
Is the power still good and can you just run diesel if you want or mix them up or is that bad?
thx
 
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