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68

Both previous posts are pretty good. I'll add a few more considerations though. On a low tank, during hard cornering, some cars will uncover the fuel pump pickup and starve for fuel. There's been some discussion for years now about keeping 1/4 tank as your minimum as the fuel provides cooling for the fuel pump. Some people argue that additional cooling ...


46

Oil as it comes out of the ground is a mixture of hydrocarbon compounds that are the remains of deposits of algae and microscopic animals, also called phytoplankton and zooplankton. Scientists have already created synthetic fossil fuels. The efforts 1. There is currently a $300 million dollar (actually much larger) effort in San Diego, California by a ...


42

What's in fossil fuel that we can't reproduce is energy. We've been making synthetic fossil fuels in one form or another for about two centuries: town gas (a methane substitute), synthetic gasoline, biodiesel, and so on. With the exception of biodiesel, however, all of these take considerable energy to produce, whereas fossil fuels can simply be pumped out ...


40

There is an unexpected effect to running with a full tank all of the time: fuel is heavy. The actual weight per gallon depends on temperature (and thus on density) but it's on the order of six pounds per gallon (or about .7 kg per liter, if you like doing all your math in base 10...). Obviously, the total weight depends on your vehicle's tank. In my car, ...


37

If the car is equipped with a modern fuel injection system, it will likely use less if left in gear and allowed to run against the transmission with no throttle as modern fuel injection systems can and do shut down the injectors completely thus use no fuel whatsoever. If the engine is at idle in neutral, the ECU will have to use a small amount of fuel to ...


35

Lean and Rich Symptoms in Motorcycle Carburetors In your post you indicate that some of the symptoms you have read are contradictory. I will try and clarify between the two conditions and attempt to give you guidelines in troubleshooting between the two. Background Motorcycle carbs have a few circuits that effect different throttle positions. Idle ...


35

The other answers are right, technically. As they say, what's in it is energy, or hydrocarbons, or whatever you want to call them. Burnable stuff. Unfortunately, the first two laws of thermodynamics tell us that artificially putting energy into a substance would take more energy than you'd get out, so it couldn't possibly be profitable [which, as an aside, ...


30

The reason is that motorcycles traditionally have the fuel tank higher than the carburetor, and the fuel feeds with gravity alone. What risks does this introduce that necessitates a manual shutoff? Without the shutoff, if the carburetor float failed to close the valve tightly enough to stop the fuel flow, then gas would continue to trickle into the carb, ...


29

The main concern with using petrol in diesel systems is that diesel is used to lubricate the fuel pump, which petrol cannot perform adequately, which will shorten the useful life of the fuel system. I think it's fair to assume that in the 5-6 seconds the fuel bowser was able to deliver no more than 2 L of petrol. 2 L out of 60 L is around 3%. I wouldn't ...


27

Knowing that gasoline does not freeze (Ok, it will start freezing at -180 degrees, but this is more than you or your car can tolerate) but that a small amount of water can accumulate in yout tank over time. So, in cold winter weather condition, like here in Canada, if you have a low level in your tank, that accumulated water could freeze and cause some ...


27

Your fuel economy change is caused by the fact you're not using the same fuel. Fuel changes twice per year from summer blend to winter blend and back again causing a change in the Reid Vapor Pressure (RVP). In summer, the hotter temperature evaporates liquids easier causing more pollution, so it is blended to lower the RVP. This blend is more costly to ...


18

I would suggest that the original problem was not the use of E10 (the vast majority of all gas sold in the US is E10 fuel due to federal mandate), but rather you received a ration of bad gas which probably had water in it, or was old gas (had been sitting for a while without new gas infused in the mix). I don't think there are any remnants of the bad gas in ...


17

The ECON button is not a placebo, though the wording from that specific web page is a bit vague. The key is that the ECON button and the Eco-Assist system are two separate things. According to Honda, pressing the ECON button configures your car to improve mileage at the cost of performance. Turning it off will improve power and reduce mileage, which you ...


16

At a base level, carburetors meter the amount of fuel they let into the engine by the amount of air that is moving through them. Vacuum is created by the piston moving in the engine and creating an open space. As the piston moves down, it creates an empty volume which pulls in air through the only opening it can find, which is the passageway through the ...


16

The main problems from misfueling a diesel car with petrol stem from the fact that (as Zaid points out) petrol doesn't provide the lubrication effect of diesel fuel and as a solvent it can actually inhibit the diesel that is there from providing lubrication and this can do nasty, nasty things to the fuel pump which can then have knock-on effects to other ...


15

I think I have an answer But bear in mind that this is my assessment with the limited information at my disposal. I'll walk through my reasoning here. If someone finds a flaw in my logic then I'm all ears. Here is a summary of your data +-------------+-------+-------+-------+-------+ | Condition | LTFT1 | LTFT2 | STFT1 | STFT2 | +-------------+-------+-...


15

IMO you have a fuel starved vehicle. Perhaps some blockage in the gas tank at the petcock filter or an inline filter between your gas tank and the carburetor. When you run the bike the fuel might not be filling the float bowl at the rate that the engine is consuming fuel. When your bike stalls the fuel is trickling into the float bowl and then you can ...


15

Carburettors are very crude in comparison to EFI systems, and so the amount of fuel entering the engine is simply a factor of the amount of air going in, which is controlled by the position of the butterfly (and hence by the throttle position). At a completely closed throttle, there will therefore still be some fuel getting in, enough to keep the engine ...


14

Most modern diesel engines (ie: engines after mid-80s) require some electricity to run because they are electronically controlled. This is due to computers controlling the fuel charge and monitoring of the engine itself. Without this, the diesel engine has no control. They also require electricity to power the primary fuel pump, to move the fuel from the ...


14

You should be fine¹ The beauty of fuel-injection management systems is that they can compensate for slight deviations in operation via feedback. The amount of compensation is commonly referred to as "fuel trim" (because the fuel injector pulsewidth is controlled ("trimmed") by the fuel-injection management). It is not uncommon for vehicles to accommodate ...


14

The problem with running the tank low in older cars is that the fuel cooled the fuel pump. The fuel pump would just hang out in the bottom of the tank with all the fuel and the fuel would wick away heat. When the tank gets low the pump is no longer covered by the fuel. With little fuel covering the pump, the pump gets hot. The pump wears more when its hot ...


14

There's 2 possibilities here. The first is that you have an electro-mechanical fuel quantity meter, and that it may be sticking a bit due to a lack of movement. The good news is it did eventually react, and hopefully it will go back to normal. As long as it shows the fuel level accurately it doesn't matter if it moves a bit slow, the major concern is that ...


13

Background Multi-cylinder vehicles with multiple carbs To port this question over to applicability with cars. This is the same issue that has plagued older Ferrari and Jaguar mechanics over the years. The 'balancing act'. If you have a V12 and 6 or 12 carbs, getting them all balanced and uniformly restrictive in terms of allowing air into them can be ...


13

Seafoam is a fuel additive which has several uses. Its primary purpose is to clean the fuel system of varnish and fuel deposits. It also cleans carbon from your combustion chamber to help reduce emissions and allow your vehicle to run better. You can also run it in your engine oil to remove sludge deposits. The following describes how you utilize the product ...


13

It sounds like you're spot on for your car. Words of advice: If you only want to change the oil once a year, use something like Mobil 1 Annual Protection, which is a full synthetic oil. It's good for one year or 20k miles. Remember, oil is dependent upon time as well as mileage. Driving it once every 1-3 weeks for 20-30 minutes is spot on for less used cars....


12

The "correct" way to clean fuel injectors is to take them out and use some specialised equipment that also allows you to check the injector's spray pattern and flow, which I doubt Firestone will have - usually only FI specialists do have that sort of kit. My guess is that they were trying to sell you some overpriced additive that you can buy at the store ...


12

Higher octane fuel does not burn as easily as a lower octane fuel. Higher octane fuels are specified where higher compression ratios are present in an engine, or where forced induction (such as turbo charging) is used. By using higher octane fuel where lower is specified, you will create no problems with your engine. It does not (by popular belief) add any ...


12

As already stated, the ignition source between gasoline/gas engines and diesel engines are different and this is the primary reason for the difference in sound. I will try to explain those differences so you you'll understand why the sound is there with one, rather than the other. NOTE 1: There is a diatribe here, but bear with me as I attempt to answer the ...


12

He is mostly right and here's why ... There is an old saying about Harley Davidson Motorcycles. They call them the "Milwaukee Vibrator" because of they way they run. These engines are a 45 deg V-Twin engine (45 degrees is the angle between the two cylinders). In the HD engine, the two connecting rods attached to the pistons share a common journal or "pin" ...


12

It's a gasoline vent tube, serving three purposes. Gasoline vapors can be especially dangerous under pressure (pretty much why it is useful), and as the temperature fluctuates it is safer to relieve the vapor pressure than it is to potentially have it build up. The gasoline vapors should preferably not be ejected onto a potential spark source (battery) or ...


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