yes my 306td again

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Wed 28 Sep 2005 16:59
yes my 306td again - thomp1983
firstly thanks to every1 that has helped so far in getting my 306 working again, the car now runs and drives like new with no sign of the white smoke issues i was having or poor starting, only thing now is that when i floor it and the turbo cuts in there is a visible puff of blue smoke, any ideas on the cause of this? the oil is coming up for change so thinking of getting some engine flush to put through it first anybody think of any other cause?

chris
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Wed 28 Sep 2005 17:43
yes my 306td again - solara
I would guess the oil seal on the turbo has a minor leak. If so, I doubt if flushing will help. Pretty common old old turbo diesels.
If you have a bosch pump, add 5-10% veg oil, it will work wonders.
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Wed 28 Sep 2005 17:46
yes my 306td again - solara
That is to your fuel tank, (not the engine oil!)
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Wed 28 Sep 2005 17:55
yes my 306td again - thomp1983
it's the lucas cav pump. not so sure about the turbo as it never did it before the head rebuild so gona change the oil as it's due and then keep an eye on it

chris
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Wed 28 Sep 2005 18:01
yes my 306td again - solara
Give the injectors a good flush with millers or redex. That should help.
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Thu 29 Sep 2005 11:14
yes my 306td again - AN Other
Out of curiosity, why does veg oil work with the Bosch pump but not the Lucas CAV? What effect does the veg oil have?
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Thu 29 Sep 2005 12:08
yes my 306td again - thomp1983
veg oil and biodiesel generally make it run quiter and smoother think it's to do with viscosity and content of veg oil compared to diesel. you can use it in 306's with a lucas cav pump, if i remember you can use about a 50% mix on the bosch pump ad about 30% max on the lucas this is due to the fact that the seals in the lucas pump are a lesser quality and break down eventually if you use to pure a mix

chris
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Thu 29 Sep 2005 12:29
yes my 306td again - mattbuttery
so you can mix the veg oil with diesel and its ok?
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Thu 29 Sep 2005 12:37
yes my 306td again - thomp1983
in sensible amounts yes, also read this post

www.pug306.net/cgi-bin/ikonboard.cgi?act=ST;f=22;t...2

it's basically following somebody who's put veg oil in there lucas pump 306

chris
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Thu 29 Sep 2005 14:40
yes my 306td again - solara
dont forget your exhaust also give off chippy fumes!
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Fri 30 Sep 2005 10:54
yes my 306td again - mattbuttery
Will watch that space, cheers.
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Thu 6 Oct 2005 20:23
yes my 306td again - paulc924
I have heard that using vegetable oil is not compatible with HDI engines. Can you verify this? Thanks
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Thu 6 Oct 2005 22:04
yes my 306td again - Richie-van-gti
thought I'd poke my nose into this thread and point a few things out.
Using 100% bioderv for long periods of time will perish the seals in the pump as it doesnt lubricate the seals like diesel dos, instead it dries them out.
Using 100% unrefined veg oil will work on just about every derv after 1990, some earlier models are fine as well but best to research.
The downside of unrefined veg oil is the fatty parts in it, they wax up injectors and pump, this is where the old lucas/cav and bosch queries come into force. the bosch pump copes with them better.
Use refined veg oil which is generally derived from used veg oil hence the chip shop smell and you dont get the waxing problems that comes with unrefined but still you will have seals perishing.

For optimal performance use either a 80% bioderv to 20% diesel mix permanently asthis will run without seal issues, no loss of performance, less smoke and no odours.
If you want to run on normal unrefined veg oil then use a 50/50 mix with normal diesel and every 4th tank fill with 100% diesel and some injector cleaner to remove all traces of waxing.

HDI's can run on these mixes but you need to clean the injectors more frequently as they are more precise and therefore more vulnerable to waxing.


PS, I have done a lot of research into these comments and currently studying chemical engineering honours degree with a view going into bio fuel engineering.
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