I suppose the typical contractor grows up to be a BMW driver.
On the other hand, I'm considering spending a few months commuting, and maybe buying a BMW for that. I'm considering a C1, on the basis that Galway traffic is a nightmare.
Does the 525 diesel have a (spit) common rail injector system? Or is it a proper distributor pump? This matters from the point of view of being able to use fatty acid esters to reduce your contribution to the Iraq War ... and may matter from the point of view of being able to afford any fuel at all in the future.
Of course using biodiesel merely means you are contributing to world hunger instead of the Oil Wars ... but at least biodiesel is more efficient than bioethanol.
I suppose the typical contractor grows up to be a BMW driver.
Now, now. There's no need for that. :-p It was quite simply one of few cars that fitted my criteria. RWD diesels are hard to find these days. :-(
I'm considering a C1, on the basis that Galway traffic is a nightmare.
I seem to remember you telling me a while back how the path to the dark side looks pleasant and smooth and is gently sloping downward. ;-)
Does the 525 diesel have a (spit) common rail injector system?
The E34 525tds has a distributor pump. The later models have a common rail system. But from what I have seen, the common rail systems can still be run on fatty acid esters with minimal modifications mainly needed for running it neat in the winter (modified injector nozzles and a fuel heater), which can be had as a kit for a few hundred euros.
It was quite simply one of few cars that fitted my criteria. RWD diesels are hard to find these days. :-(
It is a problem. I own 2 "RWD" vehicles: one is older than I am, and hasn't driven for 20+ years. The other is only optionally RWD, and spent most of the last year being FWD (until I got around to replacing the propshaft). Neither are diesel, although I'm planning to convert one of them soon, now I've found someone who will insure it afterwards. But even after conversion, it won't be particularly efficient: I'm expecting about 35mpg.
I seem to remember you telling me a while back how the path to the dark side looks pleasant and smooth and is gently sloping downward. ;-)
[Insert heavy breathing here.]
It would amuse me to park a BMW step-through next to the long line of korporate-drone-mobiles in the company carpark. The C1 doesn't even have credibility among the motorbiking crowd. The only thing it has going for it is that it's a motorcycle that's safe enough for commuting.
The E34 525tds has a distributor pump ... the
( ... )
so you might find you can only find, say "pork tallow ethyl ester" or somesuch, and that will be a quite different beast, having a higher proportion of saturated fatty acids, and a longer ester group.
The way I see it, the way forward is using the pre-cooked stuff. That way it doesn't reduce the amount available for food, while still being safely disposed of by incineration. :-) It's a bit thicker than the fresh stuff, but that's what the heater kit is for.
The pre-cooked stuff is worthwhile from an environmental point of view, but th eproblem is that there simply isn't enough to go around. Around here, the hippies all have rounds getting their local Abrakebabra to fuel their beat-up old Landys.
The US production was about 11,000,000,000 litres in 2000: call it 45 litres per person per year (source). It's possible that the USA uses less vegetable oil per head of population than Scotland, but not the UK as a whole.
How far would you get on ten gallons a year? I'd get about 600 miles, which is about 1/20th of my annual drive. But I don't do "spaceship mileage".
And, of course, the chemical composition of waste vegetable oil -- containing whatever oil was cheapest, plus the fats and oils produced by frying the food, all cooked into a polyunsaturated mess -- would be very variable. That's fine for old-fashioned engines, but on a common-rail system that depends on viscosity for accurate fuel metering, you may have a problem.
You'd be surprised how forgiving engines are to both the quality and quantity of fuel they receive. You have to get them WAY out of spec before things actually start to go wrong and stop working.
I'd be surprised how forgiving engines used to be. But the quest for ever-better fuel efficiencies and emissions controls has cut into the tolerance for poor-quality fuels.
That is how this happened, for example. No car built before 1990 would have suffered any problems with this. The lambda sensor for petrol engines is there for the catalytic convertor, which is part of the emission control system. Diesel engines have to do something similar.
Another example: when I first did the engine change on my Quantum, I first started the engine on a mixture of 5 parts petrol to 1 part diesel (which mixture passed MoT), then drove it from Egham to Bournemouth on a 50:50 mixture of diesel and petrol. It was fine. Try that in a modern diesel car. But not one you care about.
Most of your experience has been with older cars. Don't let that fool you.
There are only two things that are likely to cause a problem with petrol in diesel: Detonation and fuel pump wear. Fuel pump is the most likely thing to fail due to such abuse. You could work around that by putting half a gallon of 2-stroke oil into the fuel to make up the lack of libricating properties of petrol.
Being a 1994, I suspect my 525 would do just fine with this. But I want to fit more gauges on it for oil pressure, fuel pressure and exhaust gas temperature before I start experimenting, so that I can be reasonably sure what the before and after effects are. One of the things I want to try is upping the boost on the turbo. In theory, it should give both better part throttle economy (running leaner) and more top end power. Assuming, of course, I don't find a 1992/1993 Sierra 1.8td hatchback some time soon...
It's not that simple. If the fuel is too thin, the fuel pump will not get enough lubrication and come apart pretty quickly. Much too thin and it won't be able to build up enough pressure to fire the injectors.
The other problem is that the natural rubber seals don't react well to vegetable oil. They tend to deform and deteriorate quite quickly. This is the most common cause of fuel pump failures in vegetable oil fueled diesels.
In short - 9 times out of 10, the thing that will fail when you start changing the fuel in a diesel is the fuel pump. If you can get one rebuilt with synthetic fatty acid resistant seals you've got half the battle won. As for compensating for the fuel being too thin, well, that doesn't really become an issue unless you want to run petrol/ethanol/methanol in a diesel, which I can't see much point in doing.
The fuel pump will die in the first few thousand miles. The fuel metering problem will occur within the first few revolutions. Basically, it won't start.
Natural rubber seals don't like vegetable oil and they don't like alcohol either. But nowadays they are replaced with synthetic "rubber" components that don't mind. You could always get some spare hose.
However, the trans-esterification process that turns vegetable oil into "biodiesel" uses methanol (sometimes ethanol) and it is hard to get the end-product to be completely free of it. That's where the "Top Gear" endurance team went wrong, and suddenly discovered they had a sump full of biodiesel and none left in the tank.
Buh? How on earth did the fuel end up in the sump, without there being holes in the pistons??
And biodiesel vs. vegetable oil argument is pretty pointless in the given case. If you're using it under race conditions, there will be plenty of heat generated to keep the oil thin enough to use raw.
My guess is that the fuel pump runs off the engine, and failed in such a way that it poured diesel down the duct containing the pump driveshaft. The other end of that will either be the camshaft or the crankshaft, and the result will be the same.
The reason to point at them is not to laugh at Clarkson say anything about race conditions. It is to point out that methanol can appear in the fuel even if the fuel is supposed to be "diesel".
I think you'll find that biodiesel = 80% waste chip fat + 20% methanol. The problem with that is that methanol, similar to ethanol, has less than 1/2 of the energy density of diesel/petrol/vegetable oil.
Actually, I'm pretty sure I'll find that good biodiesel is 100% fatty acid monoester, which has more than 90% of the energy density of dino-diesel, and better combustion characteristics. Yes, the production process might use chip fat and methanol, but there is a chemical change takes place. If you represent a fatty acid as
RC02H
then the fat (or oil) associated with it is
(RCO2)3C3H5
Fat reacts with a simple alcohol (in this case methanol) in the presence of an alkali to form a fatty acid ester (biodiesel) and glycerine: a process called "transesterification". These two are immiscible and separate (with luck).
(RCO2)3C3H5 + 3CH3OH -> 3RCO2CH3O + C3H5(OH)3.
The fatty acid ester might have a chemical formula like
C17H35CO2CH3OH
(methyl stearate) which is similar enough to the C18H38 that makes up a typical fraction of dino-diesel that one can replace the other
( ... )
On the other hand, I'm considering spending a few months commuting, and maybe buying a BMW for that. I'm considering a C1, on the basis that Galway traffic is a nightmare.
Does the 525 diesel have a (spit) common rail injector system? Or is it a proper distributor pump? This matters from the point of view of being able to use fatty acid esters to reduce your contribution to the Iraq War ... and may matter from the point of view of being able to afford any fuel at all in the future.
Of course using biodiesel merely means you are contributing to world hunger instead of the Oil Wars ... but at least biodiesel is more efficient than bioethanol.
Reply
Now, now. There's no need for that. :-p
It was quite simply one of few cars that fitted my criteria. RWD diesels are hard to find these days. :-(
I'm considering a C1, on the basis that Galway traffic is a nightmare.
I seem to remember you telling me a while back how the path to the dark side looks pleasant and smooth and is gently sloping downward. ;-)
Does the 525 diesel have a (spit) common rail injector system?
The E34 525tds has a distributor pump. The later models have a common rail system. But from what I have seen, the common rail systems can still be run on fatty acid esters with minimal modifications mainly needed for running it neat in the winter (modified injector nozzles and a fuel heater), which can be had as a kit for a few hundred euros.
Reply
It is a problem. I own 2 "RWD" vehicles: one is older than I am, and hasn't driven for 20+ years. The other is only optionally RWD, and spent most of the last year being FWD (until I got around to replacing the propshaft). Neither are diesel, although I'm planning to convert one of them soon, now I've found someone who will insure it afterwards. But even after conversion, it won't be particularly efficient: I'm expecting about 35mpg.
I seem to remember you telling me a while back how the path to the dark side looks pleasant and smooth and is gently sloping downward. ;-)
[Insert heavy breathing here.]
It would amuse me to park a BMW step-through next to the long line of korporate-drone-mobiles in the company carpark. The C1 doesn't even have credibility among the motorbiking crowd. The only thing it has going for it is that it's a motorcycle that's safe enough for commuting.
The E34 525tds has a distributor pump ... the ( ... )
Reply
The way I see it, the way forward is using the pre-cooked stuff. That way it doesn't reduce the amount available for food, while still being safely disposed of by incineration. :-) It's a bit thicker than the fresh stuff, but that's what the heater kit is for.
Reply
The US production was about 11,000,000,000 litres in 2000: call it 45 litres per person per year (source). It's possible that the USA uses less vegetable oil per head of population than Scotland, but not the UK as a whole.
How far would you get on ten gallons a year? I'd get about 600 miles, which is about 1/20th of my annual drive. But I don't do "spaceship mileage".
And, of course, the chemical composition of waste vegetable oil -- containing whatever oil was cheapest, plus the fats and oils produced by frying the food, all cooked into a polyunsaturated mess -- would be very variable. That's fine for old-fashioned engines, but on a common-rail system that depends on viscosity for accurate fuel metering, you may have a problem.
Reply
Reply
That is how this happened, for example. No car built before 1990 would have suffered any problems with this. The lambda sensor for petrol engines is there for the catalytic convertor, which is part of the emission control system. Diesel engines have to do something similar.
Another example: when I first did the engine change on my Quantum, I first started the engine on a mixture of 5 parts petrol to 1 part diesel (which mixture passed MoT), then drove it from Egham to Bournemouth on a 50:50 mixture of diesel and petrol. It was fine. Try that in a modern diesel car. But not one you care about.
Most of your experience has been with older cars. Don't let that fool you.
Reply
Being a 1994, I suspect my 525 would do just fine with this. But I want to fit more gauges on it for oil pressure, fuel pressure and exhaust gas temperature before I start experimenting, so that I can be reasonably sure what the before and after effects are. One of the things I want to try is upping the boost on the turbo. In theory, it should give both better part throttle economy (running leaner) and more top end power. Assuming, of course, I don't find a 1992/1993 Sierra 1.8td hatchback some time soon...
Reply
Reply
The other problem is that the natural rubber seals don't react well to vegetable oil. They tend to deform and deteriorate quite quickly. This is the most common cause of fuel pump failures in vegetable oil fueled diesels.
In short - 9 times out of 10, the thing that will fail when you start changing the fuel in a diesel is the fuel pump. If you can get one rebuilt with synthetic fatty acid resistant seals you've got half the battle won. As for compensating for the fuel being too thin, well, that doesn't really become an issue unless you want to run petrol/ethanol/methanol in a diesel, which I can't see much point in doing.
Reply
Natural rubber seals don't like vegetable oil and they don't like alcohol either. But nowadays they are replaced with synthetic "rubber" components that don't mind. You could always get some spare hose.
However, the trans-esterification process that turns vegetable oil into "biodiesel" uses methanol (sometimes ethanol) and it is hard to get the end-product to be completely free of it. That's where the "Top Gear" endurance team went wrong, and suddenly discovered they had a sump full of biodiesel and none left in the tank.
I suppose they were lucky it didn't catch fire.
Reply
And biodiesel vs. vegetable oil argument is pretty pointless in the given case. If you're using it under race conditions, there will be plenty of heat generated to keep the oil thin enough to use raw.
Reply
The reason to point at them is not to laugh at Clarkson say anything about race conditions. It is to point out that methanol can appear in the fuel even if the fuel is supposed to be "diesel".
Reply
The problem with that is that methanol, similar to ethanol, has less than 1/2 of the energy density of diesel/petrol/vegetable oil.
Reply
RC02H
then the fat (or oil) associated with it is
(RCO2)3C3H5
Fat reacts with a simple alcohol (in this case methanol) in the presence of an alkali to form a fatty acid ester (biodiesel) and glycerine: a process called "transesterification". These two are immiscible and separate (with luck).
(RCO2)3C3H5 + 3CH3OH -> 3RCO2CH3O + C3H5(OH)3.
The fatty acid ester might have a chemical formula like
C17H35CO2CH3OH
(methyl stearate) which is similar enough to the C18H38 that makes up a typical fraction of dino-diesel that one can replace the other ( ... )
Reply
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