freeagent Posted January 20, 2008 Share Posted January 20, 2008 I'm thinking about converting my 300Tdi disco to run on Veg oil. I'm going to put the system together myself as don't realy fancy buying a kit, I reckon i can put it together for about £250 if i keep it simple. I want to use the second, internal tank for Veg oil (for a couple of different reasons) and want separate return hoses to both main and veg tanks. what do you think of the flow diagram below? I want to keep manual control of the system so will have both 3-way valves switched by the driver (single rocker switch- 2 relays), I'll probably put a timer relay in the return-line valve switching circuit so that it switches a minute of so later than the supply valve (so some of the fuel you are switching from goes back to its original tank) any comments welcome. I'm going to use a plate heat exchanger, and the chunky looking 3-way Tecalemit valves sold by biotuning.co.uk Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted January 20, 2008 Share Posted January 20, 2008 You need jamesmorfee, he seems to have a veg oil fetish and is running it on his 300TDi. Quote Link to comment Share on other sites More sharing options...
RRX Posted January 20, 2008 Share Posted January 20, 2008 Looks a good system but I would place 2 heaters in the system and not put a filter before the pump as when the veg is cold it will not pass though it at all well. I would move the heat exchange to just before the fuel filter and position another one after as the fuel filter will act like a heatsink and the veg needs to be as hot as possible before entering the IP. On mine I am running single tank with 60/40 diesel/wvo at the moment with a glow plug and water heater which turns off the glow plugs when the coolant is up to temp but i will be fitting another one before the filter soon as the filter does get a bit clogged with waxed veg oil if its very cold until its started to pump warm fuel around. If you want to be running on veg asap after the engine has started i would look at some of the heaters from www.vow2.co.uk Quote Link to comment Share on other sites More sharing options...
LandyManLuke Posted January 20, 2008 Share Posted January 20, 2008 I guess your intention is the intention to start and warm on diesel, then switch to vegi? I'd heat the vegi before filtering it, as above. You could fit an electric heater if you wanted to switch to vegi before the water was up to temperature. Quote Link to comment Share on other sites More sharing options...
Bluemoon Posted January 20, 2008 Share Posted January 20, 2008 I have a single tank system, running on wvo. in my300tdi Defender. I used to have a twin tank system but found the system I have now works better. The twin tank system ran with the oil in the main tank, with an outboard tank of diesel on the roofrack. It was switched over with electric 12v solenoid valves( looked like washing machine inlet valves but were used for irrigation, couple off quid of ebay) These were excellent . You need to check the valves can cope with the temperature of 80c, and not restrict the fuel once open, I suffered from fuel starvation with some similar ones to above and I would recommend a 9mm bore pipe. The heat exchanger I made myself, and very neat and very hard to spot. I replaced the heater rail pipe that runs from the front of the engine to the back, to the heater matrix , with 22mm copper pipe , soldiered on two flattened pipes for brackets then wrapped 8mm minibore copper down the length. Took about 3m of pipe so plenty of heat transfer. Then the engine cover would go on over that. Worked great, but every now and again I would forget to change over onto the diesel and starting in cold weather was a real pain, and flattened batteries . Hence the single system, I preheat the engine and the oil and the cab about 15 to 30mins before I go out, with a remote control(battery guard £20), using a fuel burning heater, much better, cheaper to run(runs on red diesel, legally) and uses less to heat up. Winner all round. If you want pictures , I'll try and post some up later. Camera is flat an moment, and I've never posted pictures so might take some time, from what I've heard. cheers Brian Quote Link to comment Share on other sites More sharing options...
Bluemoon Posted January 20, 2008 Share Posted January 20, 2008 It may be better to have your valves as close to the injecter pump as possible, I had mine 6" away, because a lot of diesel will be "wasted" going thru all the pipe and filter, better to have two separate filters, and two switches for the solenoids or you mix the fuels, I never had the diesel running thru the lift pump, but thru a hand primer, which i think works better. If you have no leaks the fuel will stay up by the engine and run no problems. Then that way fuel changes takes a few seconds instead of a few minutes , which adds up to costing more Brian Quote Link to comment Share on other sites More sharing options...
freeagent Posted January 20, 2008 Author Share Posted January 20, 2008 thanks for the feedback gents... there seems to be so many different ways of doing this!!! I think I will add a second heater to the system, I've seen an electric heater jacket which can be fitted to the fuel filter, under an insulated sleave, I don't realy want two separate coolant heat exchangers as it will add a large extra load to the coolant system, and if the secondary heater is electric then you have the option of switching it in or out. I'm not fussed if my warm up/ warm down times are a couple of miles as I do a 20 mile-each-way commute to work and reckon I could do at least 15 of those miles on veg using this system. I also do a few long journeys (100 mile round trip to see my folks) which could be 95% veg. I will run the engine until warm on a mixture of biodiesel and mineral diesel, and switch to 100% veg when the engine is up to temp. the only downside I can see to this system is there will be a fair bit of 'fuel A' in the system when you switch to 'fuel B' and vice-versa, hence my idea of using a timed relay to switch the return lines... Quote Link to comment Share on other sites More sharing options...
jimmy_neutron Posted January 21, 2008 Share Posted January 21, 2008 Have you considered buying the stuff from http://www.dieselveg.com ? They will probably sell you the important stuff, like valves that don't fail, a proper tested electric heater thats only used when needed, and a plate heat exchanger that other people have tested for you, and doesn't pass water into your fuel . If you want to do the manual switching thing then this could save you a bit of cash. Personal opinion... i don't agree with their choice of fitting the diesel tank in the cab. The reason for this is that a cab fitted veggie tank will slightly lift the temperature of the veggies with no effort. A bit like having warmer bath water in summer cos the incoming water is slightly warmer when using a combi boiler. Quote Link to comment Share on other sites More sharing options...
Matt B Posted January 21, 2008 Share Posted January 21, 2008 Isn't it simpler to convert the veg oil to biodeisel before putting it in a standard TDi? Or am I missing the point? Matt Quote Link to comment Share on other sites More sharing options...
jimmy_neutron Posted January 21, 2008 Share Posted January 21, 2008 Isn't it simpler to convert the veg oil to biodeisel before putting it in a standard TDi? Or am I missing the point?Matt Yep, think you missed the point Quote Link to comment Share on other sites More sharing options...
roguevogue Posted January 21, 2008 Share Posted January 21, 2008 Isn't it simpler to convert the veg oil to biodeisel before putting it in a standard TDi? Or am I missing the point?Matt This is true. Less pipework, less agro, no conversion of the vehicle, totally transferable to your next car. Of course you can get a diesel car for your wife and although you can't "sell" fuel, you can rent your processor time. The investment, both in time and money, is comparable to using wvo. Quote Link to comment Share on other sites More sharing options...
Matt B Posted January 21, 2008 Share Posted January 21, 2008 Yep, think you missed the point Could you explain, rather than being derisive? It strikes me that if you want to run your diesel on vegetable oil you have to either modify the motor or the oil. The oil is the easy one surely? Matt Quote Link to comment Share on other sites More sharing options...
roguevogue Posted January 21, 2008 Share Posted January 21, 2008 It strikes me that if you want to run your diesel on vegetable oil you have to either modify the motor or the oil. The oil is the easy one surely? Absolutely, apart from the chemicals, screwfix can deliver the whole processor in kit form.(Less a few brackets) For the £250 quoted for a vehicle conversion you could buy my processor. Quote Link to comment Share on other sites More sharing options...
Bluemoon Posted January 21, 2008 Share Posted January 21, 2008 you don't need to spend a fortune to convert, when I first converted I used the stuff I had lying around and did't pay for anything, when I realised it worked, and how good it was , I just refined the system a little. At first my valves were simple airline valves, and I just stopped the motor , lifted the bonnet and changed by hand . Ran like that for 12mths, then installed the electric solenoids for £12 from ebay , the heat exchanger was made from left over pipe, but would cost £15, if that, then the tank, old outbord tank is perfect with hand primer, even if you had to buy new, £20 to £25 , really is dead easy. Just wish I had done it 20years ago. Even now with a sngle tank system, I use a webasto fuel heater bought for £75 ebay to heat engine and oil and cab. Since then I have bought another 2 from a scrap yard , that didn't know what they were for ........ £15 each , which I am going to install into my other Landrovers. So like I said you don't need to spend fortune. Brian Quote Link to comment Share on other sites More sharing options...
TheRecklessEngineer Posted January 21, 2008 Share Posted January 21, 2008 Thought I heard my ears burning Temperature of the fuel is not important in a TDi. I find some heat is useful to help the veg through a filter, but isn't strictly necessary. The Bosch IP is quite capable of running cold veg without meltdown - the issue is the temp of the engine (a fuel burning issue) rather than the temp of the fuel (the fuel will be at the temperature of the injector when it is injected regardless of how much/little you heat it before the IP!). Avoid electric heaters - waste of money. Tests have shown time and time again that they make minimal difference to the temperature of the fuel at the expense of a lot of electricity! If you want separate returns then I would suggest what I have scrawled below (hope you can make sense of it!). It is fairly important to keep separate filters for veggy and diesel - simpy from a redundancy point of view. If your veggy filter clogs (which it will if you use WVO!) then you can always switch to diesel. It would also take >10 mins running to purge a filter of one fuel with another (tried this before). Therefore you need two filters. Two lift pumps are also necessary if you use your aux tank for veg. I would suggest using an electric one for diesel (main tank) and the mechanical one for veg - the mechanical one is more robust and will pump veg happily. An electric one that will cope with veg are ££££...assuming new of course. The electric one can be switched off when on veg, and the mechanical one will idle quite happily when you are on diesel. You also need to consider what your lift pumps are suited to - sucking or pushing The mechanical one is a pusher, so any restrictions need to be down-stream (after) it - i.e. any filters etc. Most electric pumps are pushers too.... As you need an additional filter anyway, you may as well get one with a heated base (peugeot) and do away with the heat exchanger. They come with a thermostat built in and will keep the filter at a toasty 40 degrees - more than enough to help it through the filter, without risking melting the glue that holds the filter together (can happen on some cheaper pattern part filters....halfrauds springs to mind...) You can find these filters at the scrappy for only a few £. As for the whole veggy/biodiesel debate - after fiddling with conversions and making bio, I have found it is easier to make bio. It can be done easily from waste oils and doesn't take up much extra room than what you would use in filtering the WVO for your conversion in any case. That is what I find easiest though....others may find the conversion easier - especially as you can fill up from any supermarket. Quote Link to comment Share on other sites More sharing options...
LandyManLuke Posted January 21, 2008 Share Posted January 21, 2008 I've heard from quite a few people that they can't run on 100% veg oil in the colder weather, they're cutting it with diesel and/or a little petrol. That's not a twin tank setup though, maybe it's just a cold start issue as the injectors are cold? Quote Link to comment Share on other sites More sharing options...
TheRecklessEngineer Posted January 21, 2008 Share Posted January 21, 2008 I've heard from quite a few people that they can't run on 100% veg oil in the colder weather, they're cutting it with diesel and/or a little petrol. That's not a twin tank setup though, maybe it's just a cold start issue as the injectors are cold? Spot on...cold veg is too gloopy to atomise correctly in a cold engine. This can lead to a whole load of problems with piston ring gumming and sump oil contamination. LR TDi's though seem to be fairly immune to this...possibly due to the shape of the swirl chamber in the top of the piston - this is pure speculation though...could be something entirely different Advancing the timing a few degrees can help too. Quote Link to comment Share on other sites More sharing options...
jimmy_neutron Posted January 22, 2008 Share Posted January 22, 2008 Sorry Matt. Best places to look are probably http://www.dieselveg.com and maybe .. http://journeytoforever.org/biodiesel_svo.html Main points are that veg oil has similar properties to diesel at low temperatures if veggie oil heated to 80 degrees or so. The problem is getting it to the 80 degrees or so. The twin tank with a plate heat exchanger is a good solution. Never use glow plugs to heat the oil electrically as it burns the oil. Some cars shouldn't be run on veggies. My recomendation is never convert a commonrail diesel. An indirect injection engine with a bosch injector pump is probably about as good as it gets. A direct injection engine like the 200tdi or 300tdi with a bosch pump is second favorite, but should only be done as a twin tank solution. Commonrail diesel ... like a fiesta tdci .. you will kill it. Be wary of duff information. Theres plenty of it going around. Quote Link to comment Share on other sites More sharing options...
Matt B Posted January 22, 2008 Share Posted January 22, 2008 Cheers Jimmy, nice to be enlightened! Matt Quote Link to comment Share on other sites More sharing options...
92.9 Posted February 3, 2008 Share Posted February 3, 2008 I am a little confused on what it is safe to do regarding vegetable oil in Land Rovers. I know about the Lucas injection pump issues, and that the Bosch units on Defenders are okay with it, but what confuses me is exactly what people are running their Land Rovers on. When vegetable oil is mentioned, is this straight vegetable oil, or refined using methanol and caustic soda? I was under the impression that people were running straight vegetable oil in varying mixes with conventional diesel, and was happy with that until I read the Journey To Forever site. They say that unrefined vegetable oil shouldn't be used as it won't burn properly and will contaminate the engine oil, as well as block things up, not work in cold weather and sometimes be acidic enough to eat away the inside of the injector pump! When I looked at the costs of refining vegetable oil using methanol etc it seemed a pretty pointless exercise because it looked as if it was going to work out at least as expensive as diesel from the fuel station. So, can you use straight vegetable oil in 200/300Tdi Land Rovers in any amount? If so, can you use 100% straight vegetable oil once the engine is hot, as part of a twin-tank set-up? If you can use straight vegetable oil in some amount, what percentage mix can you get away with when putting it straight into the tank along with conventional diesel and not using a twin-tank set-up? Thanks very much, Mike Quote Link to comment Share on other sites More sharing options...
jimmy_neutron Posted February 3, 2008 Share Posted February 3, 2008 I would say, assess the condition of your fuel injection pump and your fuel injectors. Running veggie oil is likely to cause your injector pump slightly more work, so if you have got 15 year old perrished rubber seals in your pump, then they are about to start leaking anyway, but the small amount of extra pressure in the pump will hurry up that leak. I also believe that 2 stage fuel injectors should be replaced every decade or 100,000 miles as part of maintenence. A poor spray pattern causes fuel to burn inefficiently, which is bad with a diesel, but worse with veggie. So in short, If youve got a good fuel injection pump, and good fuel injectors, then you should be able to run 100% SVO in a good twin tank system, with a 100% diesel startup. Change your engine oil at regular intervals, as with any diesel engine, a small amount of fuel gets into the oil. If ya look at the top of your chip pan, this is the residue that can be left in your engine and start blocking things up. However, regular engine oil changes prevents this. I would say oil change every 4000 - 5000 miles on a good engine, and depending on how much of your driving is road milage. Also when checking your oil level, feel the oil for stickyness. If it feels sticky then change the oil straight away. Mixing SVO with diesel without the addition of the extra tank.... On an old indirect injection engined car (normally ends in td, not tdi ), again if its got a good bosch pump, and good injectors, then i'd say yes. But you are talking about a direct injection engine, so i'd say no, don't do it. I know many will argue, but realistically, to ensure that the svo burns correctly, you will only be able to mix in a small amount, so the cost saving isn't there, and you've still got all the down sides, and because youre introducing cold veggie some will argue that it will not burn correctly at all, causing chip shop smells, and high engine residues. If you do decide to just stick the SVO in the tank regardless, then the amount you can get away with (the engine actually runs) depends on how cold it is outside. If your landie was a pure off road vehicle, was never gonna see the road again in its life, and was worth about a fiver, and you were doing a bit of experimenting with fuels. Then i suppose you could maybe get some keroscene (used for running oil boilers), mix it with some 2 stroke oil to give it some lubrication to help ya injection pump. Then mix this with about 50% veggie oil. It would probably work ok, not that i would of ever tried it of course. . However, theres a large difference between working for an hour, and working for 10 years. Best advice i can offer, is stick to diesel with a Tdi. If you want a little more adventure then get a proper twin tank conversion. Anything else i have seen or tried has many other hidden side effects. Quote Link to comment Share on other sites More sharing options...
92.9 Posted February 3, 2008 Share Posted February 3, 2008 Thanks Jimmy This would be for road use in a good Defender, so if it's a bit dodgy and I'll end up ruining my engine then I don't think I'll risk it. Interesting point about the chip shop smells. Is this always a sign of the oil not being burned properly? I thought that all biodiesel caused the chip shop smell! Mike Quote Link to comment Share on other sites More sharing options...
jimmy_neutron Posted February 4, 2008 Share Posted February 4, 2008 I've never run on biodiesel as i don't have a local supplier, so buying it in bulk would give me more hassle than its worth. And making the stuff seems more like a time consuming hobby than an easy solution. All veggie oil burning creates a slight chip shop smell. Burning veggie oil inefficiently stinks and also tends to smoke on acceleration. Presumably you are looking to save money on fuel easily. A good twin tank system should pay for itself in about 10-15000 miles. Everything after that is money in the bank. Quote Link to comment Share on other sites More sharing options...
92.9 Posted February 4, 2008 Share Posted February 4, 2008 Yes, the main reason would be to save money as I am a world class cheapskate. I'll have a look into twin-tank set-ups before I give up on the idea! Mike Quote Link to comment Share on other sites More sharing options...
yourekiddingright Posted January 31, 2017 Share Posted January 31, 2017 (edited) On 21/01/2008 at 2:36 PM, TheRecklessEngineer said: The electric one can be switched off when on veg, and the mechanical one will idle quite happily when you are on diesel. Hi Reckless, Can you explain how the mechanical pump will idle and if there's anything I would have to do to make idle when in diesel (electric pump) mode? Does the schematic below fit with what you were suggesting? Cheers! Edited January 31, 2017 by yourekiddingright Quote Link to comment Share on other sites More sharing options...
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