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Diesel / LPG - The first tank results are in!

General Tech Talk

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JK
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Joined: Tue Oct 22, 2002 9:00 am

Diesel / LPG - The first tank results are in!

Post by JK »

I’ve been looking around and there is very little in the way of actual feedback on Diesel Gas systems on the net – only the marketing hype from the installers which needs to be read with a little scepticism as far as the supposed power and economy gains etc.

Well, after taking the plunge and installing the LPG I have the first results on economy on the first tank(s) of fuel. I decided on a DieselGas Sequent II system installed by Hunter Gas at Dungog.

This is on a GQ Patrol TD4.2 with aftermarket turboglide Garret 25 and 2.5” exhaust. I’m setup with a 4" sus lift, 40mm bodylift and 35s running 4.1 ratios.

Before averaged 12.68L/100k over the last 40,000km (so includes all 4b trips, towing, beach driving, etc) with normal commute consumption being 12ish L/100k and with diesel at $1.379/L cost 17.49c/km in fuel.

First full tank of D+G returned 11.14K/100k diesel and 2.66 L/100k LPG included some towing, AC on, enjoying newfound power etc etc. With Diesel at $1.379/L and LPG at $0.609/L cost 15.87c/km so definitely cheaper to run. (save $16.20 over 1000km).

Power and torque definitely better - accel improvement is noticeable and the truck sits on 100km/h effortlessly. Also much happier in traffic.

I am v.happy with the LPG so far.

Oh yeah, and it smells better!

Keen to hear any other experiences with D/G.

Cheers, JK
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Post by Corgie Carrier »

What did the set up cost you and did it include a dyno?

Neale
1977 Range Rover Classic
1989 Range Rover Classic (Project)
1993 Discovery 200tdi (Project)
1995 Landcruiser Troopcarrier
1996 Discovery 300tdi (Daily Driver)
JK
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Joined: Tue Oct 22, 2002 9:00 am

Post by JK »

Corgie Carrier wrote:What did the set up cost you and did it include a dyno?

Neale
$4,900 less the $2000 rebate so $2,900 out of pocket.

Yes dyno incl - 15% incr in power and torque.
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Post by vanbox »

Your right about limited ACTUAL figures of these things, good to see.

My father has a gas system on his DTS aftermarket TD42 GU with 310 thou on the clock, and he went from avg 7.5km/L to 9 (combined gas and diesel). Mixtures is approx 10% gas.

cost him $3500 (44 L tank) less $2000 rebate.

Thats all the info i have on his.

PAUL
MUD BEERS and MAYHEM

DURAMAX POWERED GU
JK
Posts: 3229
Joined: Tue Oct 22, 2002 9:00 am

Post by JK »

vanbox wrote:Your right about limited ACTUAL figures of these things, good to see.

My father has a gas system on his DTS aftermarket TD42 GU with 310 thou on the clock, and he went from avg 7.5km/L to 9 (combined gas and diesel). Mixtures is approx 10% gas.

cost him $3500 (44 L tank) less $2000 rebate.

Thats all the info i have on his.

PAUL
Hey Paul,

That’s 13.3 L/100k down to 11.1 combined – he must be saving a few $ in fuel.

Is he happy with the performance change?

At 10% he would only be using 10 - 15L for the standard sized tank of diesel. Does this sound right? Means he would only need to fill the LPG every third diesel tank or so.

I’m using about 25% LPG to diesel. My 34L tank is perfect for my 145L long ranger diesel tank.

What system is he running? How long has he had it?

Cheers, JK
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Post by maverick01 »

im currently looking at the team green auto gas setup on a Standard 4.2 diesel GQ patrol and i was looking for actuall results

Would anyone recomend putting it on my truck
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Re: Diesel / LPG - The first tank results are in!

Post by thehanko »

JK wrote: Before averaged 12.68L/100k over the last 40,000km (so includes all 4b trips, towing, beach driving, etc) with normal commute consumption being 12ish L/100k and with diesel at $1.379/L cost 17.49c/km in fuel.

First full tank of D+G returned 11.14K/100k diesel and 2.66 L/100k LPG included some towing, AC on, enjoying newfound power etc etc. With Diesel at $1.379/L and LPG at $0.609/L cost 15.87c/km so definitely cheaper to run. (save $16.20 over 1000km).
sorry to burst your bubble a little but you got the maths a tas wrong, based on your figures $17.49 per 100km before, now your getting $16.98 combined not $15.87.

saving $5 per 1000km - negligable. 15% power and torque though :cool:

it is still better and your getting better power and no doubt putting your foot down to enjoy it.

Not being a PIA but as you said their is little actual info on this online so I thought it best to have it correct fo other to read.
*there's a rock, drive over it :) there's a bigger rock, drive over it :twisted: there's an even bigger rock, oops broke it :oops: Upgrade broken bit :bad-words:
Goto *
JK
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Joined: Tue Oct 22, 2002 9:00 am

Re: Diesel / LPG - The first tank results are in!

Post by JK »

thehanko wrote:
JK wrote: Before averaged 12.68L/100k over the last 40,000km (so includes all 4b trips, towing, beach driving, etc) with normal commute consumption being 12ish L/100k and with diesel at $1.379/L cost 17.49c/km in fuel.

First full tank of D+G returned 11.14K/100k diesel and 2.66 L/100k LPG included some towing, AC on, enjoying newfound power etc etc. With Diesel at $1.379/L and LPG at $0.609/L cost 15.87c/km so definitely cheaper to run. (save $16.20 over 1000km).
sorry to burst your bubble a little but you got the maths a tas wrong, based on your figures $17.49 per 100km before, now your getting $16.98 combined not $15.87.

saving $5 per 1000km - negligable. 15% power and torque though :cool:

it is still better and your getting better power and no doubt putting your foot down to enjoy it.

Not being a PIA but as you said their is little actual info on this online so I thought it best to have it correct fo other to read.
Yep you are right... the fuel price for the first refill was $1.279/L (not $1.379) - didn't update my calcs :oops: so yep it would be costing the equivalent of 16.98/k after - my calcs for the first refill was actually $15.87/k based on the cheaper diesel.

Means it will take a loooong time to break even but people pay a lot of $$$ for 15% increase and usually burn more fuel after.

Oh yeah, meant to mention that engine temps are running higher on the big climbs at full boost but runs much the same normally. I don't know why this is... may need a tweak on the dyno now that it is run in a bit - could be running a bit lean??? I don't know.

Cheers, JK
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Location: Brisbane

Post by vanbox »

JK wrote:
vanbox wrote:Your right about limited ACTUAL figures of these things, good to see.

My father has a gas system on his DTS aftermarket TD42 GU with 310 thou on the clock, and he went from avg 7.5km/L to 9 (combined gas and diesel). Mixtures is approx 10% gas.

cost him $3500 (44 L tank) less $2000 rebate.

Thats all the info i have on his.

PAUL
Hey Paul,

That’s 13.3 L/100k down to 11.1 combined – he must be saving a few $ in fuel.

Is he happy with the performance change?

At 10% he would only be using 10 - 15L for the standard sized tank of diesel. Does this sound right? Means he would only need to fill the LPG every third diesel tank or so.

I’m using about 25% LPG to diesel. My 34L tank is perfect for my 145L long ranger diesel tank.

What system is he running? How long has he had it?

Cheers, JK

Ill find out some more next time i see him.

cheers

PAUL
MUD BEERS and MAYHEM

DURAMAX POWERED GU
JK
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Joined: Tue Oct 22, 2002 9:00 am

Post by JK »

maverick01 wrote:im currently looking at the team green auto gas setup on a Standard 4.2 diesel GQ patrol and i was looking for actuall results

Would anyone recomend putting it on my truck
Hadn't heard of team green til now - just checked out their website and they seem to have some experience in installations.

Do you know which controller they use?
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Re: Diesel / LPG - The first tank results are in!

Post by thehanko »

JK wrote:
thehanko wrote:
JK wrote: Before averaged 12.68L/100k over the last 40,000km (so includes all 4b trips, towing, beach driving, etc) with normal commute consumption being 12ish L/100k and with diesel at $1.379/L cost 17.49c/km in fuel.

First full tank of D+G returned 11.14K/100k diesel and 2.66 L/100k LPG included some towing, AC on, enjoying newfound power etc etc. With Diesel at $1.379/L and LPG at $0.609/L cost 15.87c/km so definitely cheaper to run. (save $16.20 over 1000km).
sorry to burst your bubble a little but you got the maths a tas wrong, based on your figures $17.49 per 100km before, now your getting $16.98 combined not $15.87.

saving $5 per 1000km - negligable. 15% power and torque though :cool:

it is still better and your getting better power and no doubt putting your foot down to enjoy it.

Not being a PIA but as you said their is little actual info on this online so I thought it best to have it correct fo other to read.
Yep you are right... the fuel price for the first refill was $1.279/L (not $1.379) - didn't update my calcs :oops: so yep it would be costing the equivalent of 16.98/k after - my calcs for the first refill was actually $15.87/k based on the cheaper diesel.

Means it will take a loooong time to break even but people pay a lot of $$$ for 15% increase and usually burn more fuel after.

Oh yeah, meant to mention that engine temps are running higher on the big climbs at full boost but runs much the same normally. I don't know why this is... may need a tweak on the dyno now that it is run in a bit - could be running a bit lean??? I don't know.

Cheers, JK
totaly right 15% is sweet. interesting re the higher temp up hills, is that a higher engine temp or higher exhaust temp?

gas is a dry fuel and does tend to run hotter in petrol cars - not sure about diesels. too much fuel in a diesel (the opposit from petrol) makes them run hotter, so it might be over fueling a little on hills - or maybe its just part of the system as it gets the extra power from the extra fuel.

if its engine temp rising, then i would get a pyro fitted to check if on the hills your getting exhaust temps that are too high, as under max boost you might be pumping out some pretty hot exhaust gas and risking turbo damage.

or get it dyno tuned and double check they use a pyro guage during the test.
*there's a rock, drive over it :) there's a bigger rock, drive over it :twisted: there's an even bigger rock, oops broke it :oops: Upgrade broken bit :bad-words:
Goto *
JK
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Joined: Tue Oct 22, 2002 9:00 am

Re: Diesel / LPG - The first tank results are in!

Post by JK »

thehanko wrote:
JK wrote:
thehanko wrote:
JK wrote: Before averaged 12.68L/100k over the last 40,000km (so includes all 4b trips, towing, beach driving, etc) with normal commute consumption being 12ish L/100k and with diesel at $1.379/L cost 17.49c/km in fuel.

First full tank of D+G returned 11.14K/100k diesel and 2.66 L/100k LPG included some towing, AC on, enjoying newfound power etc etc. With Diesel at $1.379/L and LPG at $0.609/L cost 15.87c/km so definitely cheaper to run. (save $16.20 over 1000km).
sorry to burst your bubble a little but you got the maths a tas wrong, based on your figures $17.49 per 100km before, now your getting $16.98 combined not $15.87.

saving $5 per 1000km - negligable. 15% power and torque though :cool:

it is still better and your getting better power and no doubt putting your foot down to enjoy it.

Not being a PIA but as you said their is little actual info on this online so I thought it best to have it correct fo other to read.
Yep you are right... the fuel price for the first refill was $1.279/L (not $1.379) - didn't update my calcs :oops: so yep it would be costing the equivalent of 16.98/k after - my calcs for the first refill was actually $15.87/k based on the cheaper diesel.

Means it will take a loooong time to break even but people pay a lot of $$$ for 15% increase and usually burn more fuel after.

Oh yeah, meant to mention that engine temps are running higher on the big climbs at full boost but runs much the same normally. I don't know why this is... may need a tweak on the dyno now that it is run in a bit - could be running a bit lean??? I don't know.

Cheers, JK
totaly right 15% is sweet. interesting re the higher temp up hills, is that a higher engine temp or higher exhaust temp?

gas is a dry fuel and does tend to run hotter in petrol cars - not sure about diesels. too much fuel in a diesel (the opposit from petrol) makes them run hotter, so it might be over fueling a little on hills - or maybe its just part of the system as it gets the extra power from the extra fuel.

if its engine temp rising, then i would get a pyro fitted to check if on the hills your getting exhaust temps that are too high, as under max boost you might be pumping out some pretty hot exhaust gas and risking turbo damage.

or get it dyno tuned and double check they use a pyro guage during the test.
Definitely engine temp. Checked water level when I gave it’s first post-LPG service on the weekend and the coolant level was down a bit – topped it up and will see how she goes after the service.

The engine oil was black as – they reckon they run cleaner with the LPG – I’ll see if that’s the case. Oil usually starts to darken up after 1,500k or so on diesel only.

The setup I have includes a pyro linked into the ECU which cuts LPG if EGT gets too high. I don’t know what temp it’s set at though. I might see if I can get it linked into a gauge in cab. I don't want to run 2 pyros if I can avoid it.

I think one of the reasons for running hotter is the extra ponies it is putting out. Pushing a 2.5Tonne lifted truck on 35s up Ourimbah Hill at 110km/h on a 32deg day is working pretty hard! My truck always ran quite war up this hill. Now I can pull an extra 10km/h or so it’s working even harder.
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Post by rojak »

When enquiring ask if they supply you with a coc - certificate of compliancy to ensure that the installation is to aus standards.

The converters here in Adelaide when I enquired could not furnish me with a coc if I went ahead, needless to say this may be a issue with insurance if something farks up.
JK
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Post by JK »

rojak wrote:When enquiring ask if they supply you with a coc - certificate of compliancy to ensure that the installation is to aus standards.

The converters here in Adelaide when I enquired could not furnish me with a coc if I went ahead, needless to say this may be a issue with insurance if something farks up.
Definitely! - Any reputable installer will give you a "pack" of all the paperworkd and certs etc that's needed to get your LPG rebate - if you have this you will have the coc. They won't give you the rebate with out all the paperwork in place.

Cheers, JK
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Re: Diesel / LPG - The first tank results are in!

Post by midi73 »

JK wrote:
thehanko wrote:
JK wrote:
thehanko wrote:
JK wrote: Before averaged 12.68L/100k over the last 40,000km (so includes all 4b trips, towing, beach driving, etc) with normal commute consumption being 12ish L/100k and with diesel at $1.379/L cost 17.49c/km in fuel.

First full tank of D+G returned 11.14K/100k diesel and 2.66 L/100k LPG included some towing, AC on, enjoying newfound power etc etc. With Diesel at $1.379/L and LPG at $0.609/L cost 15.87c/km so definitely cheaper to run. (save $16.20 over 1000km).
sorry to burst your bubble a little but you got the maths a tas wrong, based on your figures $17.49 per 100km before, now your getting $16.98 combined not $15.87.

saving $5 per 1000km - negligable. 15% power and torque though :cool:

it is still better and your getting better power and no doubt putting your foot down to enjoy it.

Not being a PIA but as you said their is little actual info on this online so I thought it best to have it correct fo other to read.
Yep you are right... the fuel price for the first refill was $1.279/L (not $1.379) - didn't update my calcs :oops: so yep it would be costing the equivalent of 16.98/k after - my calcs for the first refill was actually $15.87/k based on the cheaper diesel.

Means it will take a loooong time to break even but people pay a lot of $$$ for 15% increase and usually burn more fuel after.

Oh yeah, meant to mention that engine temps are running higher on the big climbs at full boost but runs much the same normally. I don't know why this is... may need a tweak on the dyno now that it is run in a bit - could be running a bit lean??? I don't know.

Cheers, JK
totaly right 15% is sweet. interesting re the higher temp up hills, is that a higher engine temp or higher exhaust temp?

gas is a dry fuel and does tend to run hotter in petrol cars - not sure about diesels. too much fuel in a diesel (the opposit from petrol) makes them run hotter, so it might be over fueling a little on hills - or maybe its just part of the system as it gets the extra power from the extra fuel.

if its engine temp rising, then i would get a pyro fitted to check if on the hills your getting exhaust temps that are too high, as under max boost you might be pumping out some pretty hot exhaust gas and risking turbo damage.

or get it dyno tuned and double check they use a pyro guage during the test.
Definitely engine temp. Checked water level when I gave it’s first post-LPG service on the weekend and the coolant level was down a bit – topped it up and will see how she goes after the service.

The engine oil was black as – they reckon they run cleaner with the LPG – I’ll see if that’s the case. Oil usually starts to darken up after 1,500k or so on diesel only.

The setup I have includes a pyro linked into the ECU which cuts LPG if EGT gets too high. I don’t know what temp it’s set at though. I might see if I can get it linked into a gauge in cab. I don't want to run 2 pyros if I can avoid it.

I think one of the reasons for running hotter is the extra ponies it is putting out. Pushing a 2.5Tonne lifted truck on 35s up Ourimbah Hill at 110km/h on a 32deg day is working pretty hard! My truck always ran quite war up this hill. Now I can pull an extra 10km/h or so it’s working even harder.
The engine would be running a little hotter because you have now got about 18% more diesel exploding in each pot. And like stated above it could be running a bit rich, or your gas percentage could be to high.
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Post by frp88 »

I know that this isn't the same but I was sick of watching me blow unburnt diesel out the so I add some unleaded a HUGE difference.I'll see how the economy is after this weekend at Noosa.
LETS GO BRONCOS
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Post by Mayhem Mat »

frp88 wrote:I know that this isn't the same but I was sick of watching me blow unburnt diesel out the so I add some unleaded a HUGE difference.I'll see how the economy is after this weekend at Noosa.
not a good idea!!!!
1 litre of petrol in 1000 litres of diesel drops the flash point of your diesel from 64 deg down to about 60 deg start down that path and your fuel will be preigniting and can cause detonation and yes that is as bad as it sounds
also it will raise combustion temp which will burn out your injectors quicker and will lower the lubrication proformance of the diesel as it travels throught your injectors and fuel pump causing wear
1/2 - 1 litre in 80-90 litre tank could cause major non repairable damage
Last edited by Mayhem Mat on Thu Jan 22, 2009 9:27 am, edited 1 time in total.
got GQ Lwb much cooler than my old XJ jeep
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Post by jessie928 »

Mayhem Mat wrote:
frp88 wrote:I know that this isn't the same but I was sick of watching me blow unburnt diesel out the so I add some unleaded a HUGE difference.I'll see how the economy is after this weekend at Noosa.
not a good idea!!!!
1 litre of petrol in 1000 litres of diesel drops the flash point of your diesel from 64 deg down to about 60 deg start down that path and your fuel will be preigniting and can cause detonation and yes that is as bad as it sounds
1/2 - 1 litre in 80-90 litre tank could cause major non repairable damage
it would probably not cause damage at all,
this is done regularly in europe in winter
its also done regularly here :)

JEs
ATTACH BROKEN TOYOTA HERE--->
DUCATI <-----Worlds best warning label
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Location: mornington peninsula

Post by Mayhem Mat »

jessie928 wrote:
Mayhem Mat wrote:
frp88 wrote:I know that this isn't the same but I was sick of watching me blow unburnt diesel out the so I add some unleaded a HUGE difference.I'll see how the economy is after this weekend at Noosa.
not a good idea!!!!
1 litre of petrol in 1000 litres of diesel drops the flash point of your diesel from 64 deg down to about 60 deg start down that path and your fuel will be preigniting and can cause detonation and yes that is as bad as it sounds
1/2 - 1 litre in 80-90 litre tank could cause major non repairable damage
it would probably not cause damage at all,
this is done regularly in europe in winter
its also done regularly here :)

JEs
well how about a word from someone smarter than me

--------------------------------------------------------------------------------

TDReprint
MIXING GASOLINE AND DIESEL
(Issue 26, pages 14 – 15)

My wise old mechanic who has worked on Mercedes for years told me that if I put one gallon regular gas to a diesel tankfull after about every four tanks that it would perform essentially the same job as a fuel injector cleaner at a fraction of the cost.

I would like to hear a technical opinion.

Bill Carson , e-mail

Bill, I’ll turn the answer to your request for a technical opinion over to Brian Kmetz. As a mechanical engineer, Brian’s daily task at work is to extract BTUs through oxidation from mass quantities of methane and fuel oils. Needless to say, he knows how the fuel “stuff” works. Brian writes:

We hear this one all the time. Another version is to add one gallon of gasoline to 20 gallons of diesel fuel as a cheap easy anti-gel for winter fuel. I’ll include alcohols in this discussion because a lot of guys add it instead of gasoline. Both fuels have the same detrimental effect on diesel fuel and are very close in weight and BTU content.

The mechanic meant well and probably never saw a fuel pump or injector failure due to improper blending of fuels. But that doesn’t mean one is not risking damage, even in small dosages.

Gasoline and alcohols hit diesel fuel right where it hurts the most. Those light thin fuels will lower the cetane number and lubricity. To explain how octane and cetane DO NOT work together, I’ll have to review more crude oil and fuel fundamentals.

The light distillates that gasolines are made from have a natural high-octane index. The middle distillates that diesel fuels come from have a high cetane index. The octane and cetane indexes are INVERSE scales. A fuel that has a high octane number has a low cetane number, and a high cetane fuel has a low octane number. Anything with a high octane rating will retard diesel fuel’s ability to ignite. That’s why each fuel has developed along with different types of engine designs and fuel delivery systems. Gasoline mixed in diesel fuel will inhibit combustion in a diesel engine and diesel fuel mixed in gasoline will ignite too soon in a gasoline engine.

A lot of old-time mechanics added some gasoline to diesel to supposedly clean the carbon deposits out of the cylinders. I have never read anything that said it worked. Gasoline will make the fuel burn hotter, and hotter burning fuels burn cleaner. That’s probably where the theory got started. In the older diesel engines that belched lots of black smoke even when properly tuned, the result of adding gasoline was probably more white smoke instead of black. This might lead one to believe the engine was running cleaner. Maybe so, probably not. Here’s what happens.

Gasoline will raise the combustion temperature. This might or might not reduce carbon deposits in the cylinder. This also might or might not overheat the injector nozzle enough to cause coking on the nozzle. That’s a clogged injector tip in layman’s terms. The fuel being injected is the only thing that cools the nozzle. Diesel fuel has a lower combustion temperature than gasoline. The fuel injectors depend on the fuel burning at the correct rate and temperature for a long life. If the combustion temperature is raised long enough, the gums and varnishes in gasoline will start to cook right in the fuel injector and turn into carbon. These microscopic carbon particles will abrade the nozzle. High combustion temperatures alone will shorten fuel injector life, gasoline makes the problem worse.

Gasoline and alcohols do have an anti-gel effect on diesel fuel, but these fuels are too thin and will hurt the lubricity. Alcohols work as a water dispersant in small amounts, but also attract water in large amounts. Diesel fuel is already hydrophilic (attracts water) so why add to the problem. The old timers got away with this because high sulfur diesel fuel had enough lubricity to take some thinning. Today’s low sulfur diesel fuels have adequate lubricity, but I wouldn’t put anything in the tank that would thin out the fuel, reduce lubricity, or attract water.

Opposites do not attract in this case. Use any of the diesel fuel additives available to clean out carbon deposits, not gasoline or alcohols.

While we’re on the subject of fuels, let’s discuss another common question. What is cetane?

Cetane is to diesel fuel what octane is to gasoline. It is a measure of the fuel’s ignition quality and performance. Cetane is actually a hydrocarbon chain, its real name is 1-hexadecane. It is written as C16H34, or a chain of 16 carbon atoms with 34 hydrogen atoms attached. All HC chains are also referred to as paraffins. Cetane is a hydrocarbon molecule that ignites very easily under compression, so it was assigned a rating of 100. All the hydrocarbons in diesel fuel are indexed to cetane as to how well they ignite under compression. There is very little actual cetane in diesel fuel.

All the hydrocarbons in diesel fuel have similar ignition characteristics as cetane. Cetane is abbreviated as CN. A very loose way to think about cetane is if the fuel has a CN of 45, then the fuel will ignite 45% as well as 100% cetane. Diesel engines run just fine with a CN between 45 to 50. There is no performance or emission advantage to keep raising the CN past 50. After that point the fuel’s performance hits a plateau.

Diesel at the pump can be found in two CN ranges: 40-46 for regular diesel, and 45-50 for premium. The minimum CN at the pump is supposed to be 45. The legal minimum cetane rating for #1 and #2 diesel is 40. Most diesel fuel leaves the refinery with a CN of around 42. The CN rating depends on the crude oil the fuel was refined from. It varies so much from tanker to tanker that a consistent CN rating is almost impossible. Distilling diesel is a crude process compared with making gasoline. Gasoline is more of a manufactured product with tighter standards so the octane rating is very consistent. But, the CN rating at the diesel pump can be anywhere from 42-46. That’s why there is almost never a sticker on a diesel fuel pump for CN.

Premium diesel has additives to improve CN and lubricity, detergents to clean the fuel injectors and minimize carbon deposits, water dispersant, and other additives depending on geographical and seasonal needs. More biocides added in the south in summer, more ant-gel added in the north in winter. Most retailers who sell premium diesel will have little brochures called POPs (Point of Purchase) at the counter explaining what’s in their fuel. Please don’t ask the poor clerk behind the counter any technical questions after reading this discussion. All they need to know how to do is sell you beer, milk, cigarettes, lottery tickets, and take your money.

Texaco and Amoco are two big names who sell premium diesel in limited markets. Amoco primarily sells its Premier to specialized industrial and agricultural markets. I cannot get either in my area. Most fuel retailers buy additives or buy treated fuel. In the Northern plains states, Koch is a well-known marketer of premium diesel. I buy it when I travel into Northern Wisconsin.

Because there are no legal standards for premium diesel yet, it is very hard to know if you are buying the good stuff. I have good news. An ASTM task force has drafted standards for premium diesel. When the new specifications are accepted, information will have to be posted on the fuel pump. Retailers will no longer be allowed to label cheap blended diesel as ‘premium.’ They will have separate pumps with clear labels on both informing the customer what is being sold. The marketing and labeling will be the same as with regular and premium gasoline. Retailers selling the real thing use this system now. Enforcement of all fuel standards is done at the state level in the USA.

Diesel fuel is an international commodity for industry. Therefore, you should be picky about where you fill up. Shop for price from a large volume retailer so you have the freshest fuel. That’s about the best advice I can give.

The 1994 legislation and reformulation of diesel fuel in North America is due to an international effort for lower emissions. Cleaner diesel emission laws are on the way. Diesel fuel is going to be reformulated into a cleaner fuel in general. Without getting too technical (this is over-simplified and very generalized), diesel fuel for the most part is made up of two different hydrocarbon families: paraffins and aromatics. The paraffins have a naturally high cetane index, burn clean, but cause the annoying gel problem in winter. The aromatics have a naturally high lubricity, low cetane index, and cause a lot of diesel emissions and soot. Reformulated diesel will have a higher paraffin content, higher cetane number, and a much lower aromatic and sulfur content. It will also be more prone to jelling and have a lower lubricity. Big oil is working on improved additives as I type this.

The reason nothing has happened yet is because of infighting in the EPA on its new Tier II Emissions standards for gasoline and diesel. Ultra-clean technology for gasoline and diesel engines is almost ready to go, but the refiners have to lower the sulfur level drastically in both fuels. The EPA should formally set something by year 2000.

Brian Kmetz


I still say not smart
got GQ Lwb much cooler than my old XJ jeep
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Post by Mayhem Mat »

anyway wasn't this about diesel and gas
got GQ Lwb much cooler than my old XJ jeep
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Post by love ke70 »

unleaded fuel may lower the ability of the diesel to burn due to the cetane and whatever whatever, but LPG has a octane of 102+
somewhere up to 130 from the right servos. but it makes the diesel burn better...why? because it makes it burn sooner and faster. which is why you have to be careful with the tune to avoid knocking.
and LPG is gonna create all the issues he is talking of unleaded creating.
except maybe the lubricity issue in the injectors, but will be the same in the head though...

ive just got D-GAS fitted up on my ute, for less than the rebate, buying the unit direct and finding a friendly gas fitter to do the lines, and tuning myself, was going to get tuned a workshop who was keen to learn, but no dyno and a bad attitude has put me off.

before the gas, diesel usage over the past 30,000km had been averaging 12.36.
in driving since new year to install, which was only 1600 km had averaged 11.77 over 3 fills.

upon install, wacked a big 60 thou jet in and running about 17psi gas pressure, which is then boost matched.
did 2 days driving and used 10.3L/100km of diesel and 3.26L/100km of gas. yes, thats nearly 32% gas.
diesel was at 107.9 and gas was 55.9, need to find cheaper gas, havnt shopped around yet haha.

so not that much money saving, it knocks a bit in 4th especially below 1500, so i need to drop a smaller jet into it, but ill do that after the next fill, so i have a full weeks travel to be sure of my figures.

a bit less LPG and getting off the loud pedal a bit mroe will help my economy a bit further, but im happy with the system.

fucking rocks on the highway.

around town its still a bit of a pig as it doesnt come on til 1psi of boost, so i need to tune the diesel a little to get more spool as im lucky to see any boost in first, and it takes a while in second too.

also feel it cutting in and out as you float around the 1psi at 60/70/80 cruise speed, so it can make it hard to maintain a speed, but i can put a microswitch in so it comes on at .75psi or something. should fix that issue.

how do the dieselgas systems work in this regard?

the engine of course runs hotter with the LPG, as its more fuel going bang, so more heat produced, mine spools much better now, with factory NA diesel tune, or near enough to it, it was a prick, but with the gas on it now spool is much improved :) my temps used to max out at 470 on a lonngg climb with plenty of boot in 4th, ill now see 550 easy, and then get a little worried and get off the pedal a little.


hmm, ive totally lost my train of thought....

where was i going with this?
any questions?
ill be back with my info on monday or tuesday as thats when ill be filling up again.

oh, btw, 45L tank under the tray on my ute, as i already had it, and had been dated recently so that was one of my key reasons for going diesel gas, as they still run a liquid pick up, whereas alot of the others run a vapour pick up and can create issues further along the track.

and PS, dieselgas is post turbo, how much of a difference this makes to life on everything i think is fuck all, but it makes me happy...



whats the deal with the new dieselgas systems? my mechanic mumbled something about them mixing the lpg with hte fuel...didnt see how, but with liquid injection on dedicated gas cars i guess its possible?..

sorry, ill go back to my box now :lol:
97 GQ patrol coilcab. TD42, safari turbo kit with fiddled turbo, D-GAS kit. dyno results to come...
4inch lift, king springs, efs and procomp shocks
315/70R16 cooper ST's
found fuel economy...
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Post by pongo »

Mayhem Mat wrote:anyway wasn't this about diesel and gas
Bahahaaha, You got owned while being a smart ass then you say its off topic.

My TD patrol hasnt seen a drop of diesel in about 2.5 yrs but sees petrol in its belly on a daily basis, Its still working better and harder than ever.

Next time just admit you have been corrected and thank them rather than act like a Bitch on heat.

Cheers

P.S. Bloody Kids
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Post by love ke70 »

what do you mean you TD hasnt seen diesel in two years?
you running a diesel on straight petrol or have i missed a step?
97 GQ patrol coilcab. TD42, safari turbo kit with fiddled turbo, D-GAS kit. dyno results to come...
4inch lift, king springs, efs and procomp shocks
315/70R16 cooper ST's
found fuel economy...
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Post by frp88 »

Mayhem Mat wrote:
frp88 wrote:I know that this isn't the same but I was sick of watching me blow unburnt diesel out the so I add some unleaded a HUGE difference.I'll see how the economy is after this weekend at Noosa.
not a good idea!!!!
1 litre of petrol in 1000 litres of diesel drops the flash point of your diesel from 64 deg down to about 60 deg start down that path and your fuel will be preigniting and can cause detonation and yes that is as bad as it sounds
also it will raise combustion temp which will burn out your injectors quicker and will lower the lubrication proformance of the diesel as it travels throught your injectors and fuel pump causing wear
1/2 - 1 litre in 80-90 litre tank could cause major non repairable damage
how can a diesel pre-ignite it compresses air and then adds the fuel as where a petrol engine does it with fuel. well the big test will be tomorrow when we tow the too noosa.
LETS GO BRONCOS
JK
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Post by JK »

love ke70 wrote:
around town its still a bit of a pig as it doesnt come on til 1psi of boost, so i need to tune the diesel a little to get more spool as im lucky to see any boost in first, and it takes a while in second too.

also feel it cutting in and out as you float around the 1psi at 60/70/80 cruise speed, so it can make it hard to maintain a speed, but i can put a microswitch in so it comes on at .75psi or something. should fix that issue.

how do the dieselgas systems work in this regard?

and PS, dieselgas is post turbo, how much of a difference this makes to life on everything i think is . all, but it makes me happy...

whats the deal with the new dieselgas systems? my mechanic mumbled something about them mixing the lpg with hte fuel...didnt see how, but with liquid injection on dedicated gas cars i guess its possible?..

sorry, ill go back to my box now :lol:
My setup is almost invisible, feels much the same to drive but more grunt, very smooth and turbo spools up nicely from abut 1200rpm.

I have the Diesel Gas Technology kit with the Sequent II electronic controller. Automatically injects LPG depending on engine load and revs. Makes for a very smooth throttle curve, can’t feel it cutting or out, probably because it doesn’t.

LPG is injected pre-turbo and the turbo acts as a mixer. Certainly doesn’t mix with the fuel until in the chamber.

Cheers, JK
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Post by love ke70 »

frp88 wrote:
Mayhem Mat wrote:
frp88 wrote:I know that this isn't the same but I was sick of watching me blow unburnt diesel out the so I add some unleaded a HUGE difference.I'll see how the economy is after this weekend at Noosa.
not a good idea!!!!
1 litre of petrol in 1000 litres of diesel drops the flash point of your diesel from 64 deg down to about 60 deg start down that path and your fuel will be preigniting and can cause detonation and yes that is as bad as it sounds
also it will raise combustion temp which will burn out your injectors quicker and will lower the lubrication proformance of the diesel as it travels throught your injectors and fuel pump causing wear
1/2 - 1 litre in 80-90 litre tank could cause major non repairable damage
how can a diesel pre-ignite it compresses air and then adds the fuel as where a petrol engine does it with fuel. well the big test will be tomorrow when we tow the too noosa.
because there is a delay between injecting the fuel and it combusting, change this, and you can make it pre-ignite
97 GQ patrol coilcab. TD42, safari turbo kit with fiddled turbo, D-GAS kit. dyno results to come...
4inch lift, king springs, efs and procomp shocks
315/70R16 cooper ST's
found fuel economy...
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Post by KiwiBacon »

frp88 wrote: how can a diesel pre-ignite it compresses air and then adds the fuel as where a petrol engine does it with fuel. well the big test will be tomorrow when we tow the too noosa.
A diesel can't preignite until you add a fuel that's present before ignition. Like LPG fed in through the intake.

BTW, the main point in that whole novel up higher about mixing petrol and diesel was reduced lubrication, preigntion didn't feature, instead the opposite was noted. Gasoline in diesel can inhibit combustion.
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Post by mike_nofx »

pongo wrote:
Mayhem Mat wrote:anyway wasn't this about diesel and gas
Bahahaaha, You got owned while being a smart ass then you say its off topic.

My TD patrol hasnt seen a drop of diesel in about 2.5 yrs but sees petrol in its belly on a daily basis, Its still working better and harder than ever.

Next time just admit you have been corrected and thank them rather than act like a Bitch on heat.

Cheers

P.S. Bloody Kids
Are you serious? You run a diesel on straight petrol?

Either you are full of crap, or a complete moron (who has so far been very lucky)...
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Post by jessie928 »

mike_nofx wrote:
pongo wrote:
Mayhem Mat wrote:anyway wasn't this about diesel and gas
Bahahaaha, You got owned while being a smart ass then you say its off topic.

My TD patrol hasnt seen a drop of diesel in about 2.5 yrs but sees petrol in its belly on a daily basis, Its still working better and harder than ever.

Next time just admit you have been corrected and thank them rather than act like a Bitch on heat.

Cheers

P.S. Bloody Kids
Are you serious? You run a diesel on straight petrol?

Either you are full of crap, or a complete moron (who has so far been very lucky)...
so your actually believing that it would be indeed possible that he could be running his mq on straight petrol? ( a lucky moron)

assumtion is the mother of all F@@#ups.

muhuahaha

Jes
ATTACH BROKEN TOYOTA HERE--->
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Post by KiwiBacon »

mike_nofx wrote: Are you serious? You run a diesel on straight petrol?

Either you are full of crap, or a complete moron (who has so far been very lucky)...
Hook, line and sinker. :lol:
I suspect he's running veggie oil or something similar which is thinned with petrol.
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