This is the first I've ever heard of this. What are your sources?drivbiwire said:Truck stop fuels generally have high sales and turnover. Diesel does NOT go bad like gasoline. "Fresh Fuel" is a myth and stems from the fact that diesel fuel will absorb water which places greater risk of triggering the CDI's fuel water sensor and requiring a filter replacement.
Truck stops have some of the worst fuel filtering systems, this can lead to more frequent plugging of your CDI's fuel filter.
H-TownBenzoboy said:This is the first I've ever heard of this. What are your sources?
The expected life of a diesel fuel is indicated by the oxidation stability test ASTM D2276. The test measures how much gum and sediment will be deposited after keeping the fuel at 120°C in the presence of oxygen for 16 hours. It roughly corresponds to one year storage at 25°C. A result of less than 20mg/L of sediment and gum after the test is considered acceptable for normal diesel.
The ageing process can be accelerated by the following conditions:-
• Contact with zinc, copper or metal alloys containing them. These metals will quickly react with diesel fuel to form unstable compounds.
• The presence of water. Water allows the growth of fungus and bacteria, these produce natural by-products such as organic acids which make the fuel unstable.
• Exposure to high temperatures.
• Exposure to dust and dirt which contain trace elements that can destabilise the fuel, such as copper and zinc.
Again the primary concern with ALL Diesel fuel is moisture. Contact metals are less of a concern because diesel fuel is stored in Diesel specific fuel tanks where these materials are NOT used. It is accepted that diesel fuel provided moisture is kept in check has a shelf life in excess of 5 years in certain cases. Often fuels stored for stanby generation get anti-microbial dosing to prevent algea and bacterial formation in the fuel. Typically these tank systems are kept full and use a sealed tank system to prevent the absorbtion of water from the air. Also these tanks use summer fuels with maximum BTU content, this presents the problem of gelling during the colder winter months. Fuels are dosed on anti-gel additives to lower the fuels gel point.PROLONGING THE STORAGE LIFE
Issued : February 7, 2002 ADF1402
Supersedes : February 14, 2000 Page 2 of 3
A.C.N. 004 085 616
Marketing Technical Services
• Ensure that the fuel is not in contact with any surfaces containing zinc or copper or compounds containing those metals (eg. brass). If those metals are present then a metal deactivator additive may help.
• Establish a regular fuel maintenance program to ensure that water and dirt is removed from storage tanks. This will also remove any chance for fungus to grow.
• Water should be drained from the storage tanks weekly. The frequency can be extended if the tank shows no tendency to collect water but should be done at least monthly.
• Tanks should be kept full to reduce the space for water to condense, maintaining tanks half full increases the water build up and promotes corrosion in the top half of the tank. Most water will come from condensation as the tank breathes, the rate at which water collects will depend on local climate and will be higher in hot humid coastal areas.
• Tanks should have a well defined low point where water will collect and can be drained. For example, cone down bottoms.
• Establish a system for filtering the contents of the main storage tank through a recirculating filter system. This can be made automatic and will reduce the potential for problems by removing sediment and gums. The filters should be checked and changed at regular intervals. When the filter change interval reaches a certain frequency then the fuel should be changed over.
• Tanks should be emptied and cleaned at least once every 10 years, or more frequently if there is a major contamination.
• Ensure that the fuel supplied conforms to a recognised specification and ensure the fuel matches the winter cloud point for the area to avoid filter blocking by wax drop out in cold weather. .
• Always purchase fuel to replenish stocks in the winter season April - August. This will ensure that the fuel will not cause wax problems whatever season it is used.
• Obtain assurances from the supplier that all components are fully refined to promote stability.
• Establish a monitoring program whereby samples are taken at regular intervals to monitor the condition of the fuel. The samples can be examined at the site visually for evidence of haziness, sediment, darkening or sent to a laboratory for testing.
• Regularly turn the fuel over. If possible, plan the fuel usage so that it will all be used within 1-5 years and replaced with fresh fuel.
Water level sensor attached to top side of filter
uses two electrodes located on bottom portion
of sensor If high water level sensed approx.
50% filter housing capacity, water level indicator in
instrument cluster illuminates
DBW ..drivbiwire said:It's just my opinion but I would tend to stay away from a used diesel. These are motors that you buy and keep, owners that turn them over in a year or two more than likley did not take care of them the way they need (Not that they need more care, but simply different care). If I were to buy one it would be thru a private party where you could meet and talk to the previous owner to get the scoop. If they can tell you the exact type of oil used verses some guy blurting out "Synthetic" additionaly when the last fuel filter was changed you may have a winner.
I stopped owning gas cars a LONG time ago, gas motors are boring and insulting by virtue of the hopeless inefficiency of an otto-cycle, even my daily driver at work detests benzine... In thrust we trust
Yeah, but I've been up close with one. You can still tell it's a diesel, though it's not as loud as a OM61x is.drivbiwire said:Clatter? Whats that? The CDI is pretty darn quite!
I've seen a trend here in town that's the exact reverse. I'm now finding diesel fuel for less than regular unleaded for the first time in a good while.lear31a driver said:Third, it's a known quanity that diesel pump prices are going to remain higher than premium fuel prices. As the demand for diesel increases, more light diesel vehicles produced and sold will drive the prices. See the attached from a multi page study by the DOT supplied by fuel futures analysts:
It's the same here in Florida. Diesel is less than regular unleaded at many stations.H-TownBenzoboy said:I've seen a trend here in town that's the exact reverse. I'm now finding diesel fuel for less than regular unleaded for the first time in a good while.
The unexpected can change depreciation. For instance, 2004 and 2005 Volkswagen models with fuel-efficient diesel engines have appreciated, not depreciated, the past year as gasoline prices climbed, DeBacker says.
The diesel way
The ‘high-maintenance’ myth about diesel cars scares many away. They are cheaper to run, and it’s not just the fuel.
Veeresh Malik, Outlook Money
page 1 of 1
Diesel or petrol? Diesel, I’d say, if you can take the higher initial cost, know a bit about maintenance, can live with some noise and vibration, and do 2,000-plus kilometres a month in the city. I was a card-carrying member of the anti-diesel lobby till about a decade ago; now, I’m a happy convert. And I do about 1,000km.
All else being equal, a diesel car scores over its petrol cousin in the same category. Diesel cars give about 50 per cent better mileage at 30 per cent lower fuel cost. Also, owing to their popularity with taxiwallahs, diesel cars have higher resale values.
Warnings on maintenance, and wear and tear scare away many. But those perceptions are wrong; wear and tear as well as maintenance on diesel cars are comparable with petrol cars. Most diesel carmakers now specify a 10,000km interval between services and engine oil replacement, with minimal checks in the interim. One manufacturer claims that the new-generation engine oils work very well for a good distance in city conditions, but that in towns, factors like dust, weather, and frequent gear changes necessitate earlier oil changes. What about the smoke? Tip: wait for the glow plug to go off before starting the car. It takes only a few seconds. You could also keep the filters and mufflers in good shape–wonderful for fuel economy too–and get the injector nozzles checked for dribbles during servicing.
Now for the noise. While not quite a myth, it should not restrain you from going diesel. This is because refinements in cabin acoustics, anti-vibration dampers and suspension components mean that once the car has run for a few minutes, you can hardly tell from the inside whether it is diesel or petrol. In fact, when cruising the highways, a diesel engine sounds positively better than a straining petrol one.
Fuel quality, that old diesel car owner’s bugbear, has improved to a large extent. I could point to the range of premium fuels available, but their quality, on which I have held forth often enough, remains debatable. What I am talking about is the fact that diesel comes from new, privately owned, and increasingly sophisticated refineries making for visibly better performance. There are a string of these new private-sector filling stations on the highways, which truckers say sell decent-quality diesel.
Just a few RECENT factual tidbits to chew on.Owners of diesels are a club of sorts, they have history on the road, hybrids don’t. And with an eye on the past, we have serious questions about the hybrid’s future. The hybrid is a vehicle of science fiction. One can only wonder what sort of episode an owner will encounter when hybrid-drive refuses to kick in. Unfortunately the future cannot be seen in order to answer several begging questions. Where the diesel is proven, questions remain regarding the longevity of the hybrid’s electric motor and batteries. Personally I consider the hybrid to be a “one time use car.” In essence you are the last owner. Why is this you ask? Well, have you priced the cost to replace those high-tech batteries and assorted components? Also, who will be qualified to fix the car 10 years from now when the warranty has run out? Interested buyers should also talk with current owners of high-mileage hybrids about their fuel economy once the batteries lose their ability to hold a charge. It is quite dismal. With all of this you have to wonder if there will be a used market for cars past their warranty period. But today the public stands willing to trade the certainty of high MPG at the pump for uncertainty of a de facto “maintenance balloon note” in the future. In contrast the diesel owner banks on minimal inconvenience at the pump for a long-term future with known results. Given this the choice should be as clear as day.
Plentiful sources for fuel
Cheaper to maintain.
Made by a manufacture with a history of diesel motors.
Proven method in the long term
Can run Biodiesel
A normal car
Must remember to use diesel not gas
Not as fast off the line
Misperception as smoky and smelly
Misperception as unreliable
Fuel not available at every gas station
Misperception as loud
Consumers unfamiliar with maintenance and care differences.
Not available new in all markets.
Gasoline Hybrid car pro and cons
Cheaper fuel costs
Quiet when in electric mode
Positive public image.
Positive image of manufactures
Hybrid transition from gas to electric is seamless
Fuel available everywhere
Ideal in urban and low speed environments
Perception of Eco-Friendly caring owners
Must be serviced at the dealer
Long-term cost of operation is unknown.
Replacement costs of batteries are high
Few owner serviceable/repairable parts
Long-term reliability is unknown
Long-term residual value is unknown
Concessions of comfort and normalcy made for efficient operation
Resale value is unknown
Long-term durability unknown
5000 gallon fuel tank + Lack of water monitoring + lack of 2 micron fuel filtration + (maybe) High sulfur + low throughput off-road diesel = Mercedes Benz'z fault for poor reliability and 7 major fuel system repairs? Just wanted to see if I am reading that right...lear31a driver said:I owned a '98 300TD, have addresses out of the State of Calif , bought out of state and drove the car for 113,000 miles. Used it as a company vehicle. We had two diesel trucks, a 5000 gallon diesel tank on the shop property which compelled the purchase of a diesel MB. I had seven major repairs done to the engine by MB, most involving the high pressure pump, two involved bearings.
Without getting into the specs for European Rapeseed and un-regulated US Soy Based biodiesel, lets just say Bosch already knows B100 can and does work in the CDI WITH approval. The concern for Bosch is the lack of consistent production guidelines leaving greater than 2000ppm unreacted Methanol, higher oxidation (lower stability) as well as a host of other factors. Biodiesel when properly produced has very similar characteristics to #2 diesel fuels, again the key is properly produced...DBW ... put 50-100% biodiesel in your CDI .. watch how long it runs before leaks start sprouting. You forgot the corrosive nature of biodiesel to the fuel supply system.
You can add all the oil filters in the world and you know what? It aint gonna do a darned thing! You see soot formation occurs in the nanometer range....15 gallon oil sump and two aftermarket filters...The oil filters come from experience as to what a diesel does to lubricating oil. Go ahead and let your Mobil 1 go to sludge, MB doesn't expect you to own the car for more than 4 years anyway.
Well, based on your use of 15 gallons of oil in an engine that only requires 4 gallons of a 5w40 CI-4+ lube I can understand how the economics plays against your poor choices in engine servicing. Given the fact Mercedes uses 2 gallons and goes 13,000 miles between drains (Oil is certified for 19,000miles/30,000km from the factory). We can blame US dealerships for not using properly rated synthetic oils a few years back (See the $23Million dollar lawsuit) thus why we are limited to 13,000 miles between changes. If the US could come to grips with going 45,000km between oil changes using properly rated lubes imagine how cheap owning a modern vehicle can actually be, Again we can thank the mentality you apearantly share for this situation...Diesels are fine engines, when maintained and cared for far and above their gas counterparts. They will deliver higher MPG, but the economics come out in favor of gas engines most every time. Again, experience speaking .. no cut and paste.
26mpg is what I get romping around town...Trust me it's nothing to brag about! Hell I get 26mpg driving at 110 mph in the CDI Benz and trust me the motor is FAR from straining! I guess you keep confusing your older 300 IDI which used the same low pressure rack system as the original diesels. This motor would in fact struggle up the hills as you suggested, the CDI is a different beast all together! Just today I was driving up the autobahn at 200 clicks outside of Frankfurt...yup in an E320 CDI By the way I even caught the scent of Biodiesel outside the terminal building, guess these oil burners over here really do have it figured out.By the way, my last trip in the S500 was almost purely highway, tank to tank. I got 26MPG and at 70MPH, the engine was barely hitting 1700 RPM. Now that is a far cry from straining its power range.