sugar equals engine death?

Jarvis,

Despite rumors to the contrary, the old sugar-in-the-gas-tank trick doesn't do a whole lot. Regular granular sugar does not readily dissolve into gasoline. Basically the larger grains will end up clogging the various fuel filters and not much more. If the sugar has a large quantity of finer powdered particles, then some may escape being trapped by the filter. Any sugar that makes it into the combustion chamber will be rapidly caramelized by the combustion event. This will result in baked on carbon deposits. That's about it.

The biggest hassle with sugar in the tank is usually fuel starvation caused by intermittently clogged filters. On older vehicles with poor filtration and fitted with a carburetor, then some amount of carb damage/sticking may occur. This may be why the legend continues to this day.

Good Luck
Bryan Carter

Leads to an interesting question. Sugar is basically carbon so if you dissolve it in say acetone would it make a good fuel ??

Dave

not for a gasoline engine!

Jay Maechtlen

I don't know about mixing sugar with acetone, but I do know you can readily make ethanol from sugar. Also it's been shown that you can get hydrogen (for fuel cell cars) by exposing a sugar/water solution to a heated platinum catalyst. Other than that, I have no clue.

Bryan Carter

I have heard from those who fix sugar tampering the same story. Clogs the filters. They did say if there is water in the tank such as from condensation, it can make a gummy sticky mess that wreaks havoc on EFI fuel pumps and clogs injectors and the return valve on the fuel rail. Haven't heard of any damaged engines.
Ken

Remember that many of the 'sugar-in-the-gas' stories are very old. That makes me tend to favor the 'caramelization hypothesis' -- since engine stickiness and not just a transient 'potato-in-the-exhaust' stoppage is supposed to result.

Sugar is a carbohydrate -- containing carbon, oxygen, and hydrogen. Take a look at an organic-chemistry textbook to see what the ends and center of a typical sugar molecule contain. There isn't an objective reason why such a material couldn't qualify as an 'oxygenated fuel' -- the problem is that it's a solid, and tends to react rather than igniting under the transient combustion conditions in an automobile engine -- particularly the long-stroke and indirect-ignition conditions in older F- and L-head auto engines of the '20s and '30s...

Sugar under some conditions can make an excellent -- and clean-burning -- fuel. There's an old demonstration of this: Take a sugar cube, dip the corner in ash, and light that corner with a match. The sugar will proceed to burn with a blue, smokeless flame, until it's gone. But it takes a while to do that, and I've noticed that some attempts to speed up the process (like blowing on the tiny flame) result in caramelizing or blackening -- which cuts off oxygen to the flame region and can actually stop the burning. The high surface area of the compacted grains is essential to burning, too: I've never succeeded in cleanly igniting a piece of rock candy successfully, even with pure oxygen...

Actually, I found the gas cap off of my car once, and traces of sugar around the filler, and some in the filler neck. I was unable to determine how much had gotten down the filler neck.
I ignored it. (well, I did clean the area around the filler and make sure the filler cap was in place).
I had no problems with the car that I could relate to fuel contamination. (luck? maybe...) I did get rid of the car at 84k miles for other problems. The powertrain was solid, though.

That was an '80 Fairmont, with the 200 cid inline 6.


Jay Maechtlen

I'm just curious as to what legitimate reasons you might have for asking this question?
Hmmm?

Hi
I purchased a toyota V6 Dually delivery van from our local Dunkin Donuts because an ex employee apparently put sugar, or maybe a sugar/water solution in the gas tank.
I am not sure what it did to the motor cause I sold it to a stranger whom I had informed as to the uncertainty of the motor.
What I CAN tell you is that when I pulled the tank, it was F**KED up beyond use, ditto for the fuel line. There was a thick cakey rust layer in the tank, and lines.

I installed the engine of my liking and
converted the truck to propane

Typically your average sugar vandal won't put enough sugar in the tank to make much of a difference. Now if you get a determined sort of fellow, who pours a 5 pound bag into your tank, then you most assuredly will experience some degree of problems. In real large quantities, sugar will simply fill the tank well from which the pump draws in the fuel. The vehicle will start, idle for a bit, then die.

If all of your vehicle's fuel filters are intact and functioning, then sugar in the tank will only prove to be a minor annoyance. You drop and flush the tank and lines, replace the filters, fill her up, and you are on your way. Hopefully you'll be on your way to your nearest auto parts vendor to purchase a nice locking gas cap.

In a former life I worked for a Honda dealership, and from time-to-time we saw this issue. It never resulted in engine damage. Granted, it is possible, but it's usually not the case. I can remember several times dropping the tank on a car for a completely unrelated issue, and finding some quantity of sugar/sand in the tank. With the owner of the vehicle having been unaware that it was even in there.

Bryan Carter

Thanks for all the replies.

Rob45
I asked this question because I hear stories of it wreching an engine....this did not make sense to me. I figured it should only gum up the fuel system and maybe introduce carbon buildup. I figured I'd ask about it here since you all seem like knowledgeable people. If I had in mind trying it out, I would do just that and not ask. I can think of many other sure fire ways of disabling someones vehicle.