Fuel Gelling in Winter?

Hi!

I have a 1984 Sierra with the 6.2L. Granted this is at least two generations away from your Duramax, but I'd think the extreme basics of the fuel systems wouldn't have changed that much. I'm located in Illinois where the winters can get downright bitter...and apart from the truck becoming extremely hard to start in the cold, I've never had to deal with fuel gelling or waxing on me.

I'm not real choosy about my fuel either. I can't be. Up until recently there was only one place to get Diesel fuel. This usually made things entertaining when I waited until the weekend to get fuel and found that one place to be closed.

Again, I've never had that problem. I have never taken any special precautions on my truck (except for a block heater) in cold weather.

Never used anything like one on my truck. (Notice a theme here?) Even in bitter cold (at least freezing, often less) on the highway, once warmed up my truck would stay right around 200 degrees F as per the gauge.

There are two different grades of Diesel fuel. I know that they are known as

1-D and 2-D. Beyond that I don't know much about them or what is best for winter use.

When it gets cold enough to need a winter coat, use it. That's about the best advice I could offer apart from saying that when your truck gets hard to start it is a good time to use it.

I don't know what, if anything the block heater will do to keep fuel from gelling. I doubt it can do very much as its purpose is to warm the block and the coolant/water mix inside it. But it will make cold starting MUCH easier and probably doesn't hurt the engine one bit.

One thing I can say--if you don't have a block heater, you probably want one and you certainly want to use it. It makes the difference between my old truck requiring quite a few tries to get started and it popping right off as though it were springtime outside.

Good batteries are also a very good idea. Get the best ones you can afford...no, scratch that. Get the best ones you can buy, even if you can't really afford them. I don't know if the new ones are any easier to start, but my old truck usually needs a lot of what the batteries can give...and I've seen times when dual 900 CCA batteries could not get it started before dying.

William The Guesser

You won't have waxing problems until the temps get into the 20'sF and by that time all of the stations have gone to winterized diesel which is normal diesel with a mixture of Kerosene. So do what your owners manual say to do when operating in the winter time. You should also keep the tank half full or more.

Ok,

Don't worry about it winterized diesel will resist solidifying on you. If you are really worried then get something like "Power Service" or some other type of diesel conditioner and add it to each tank full. I know the guys with the Power Strokes use this when it gets sub zero and nothing has a fuel system worse then a Ford Diesel.

I have no idea what you are talking about??? Are you talking about a engine blanket? If so I would not even worry about that unless you are in northern Canada or Alaska. You use engine blankets when the engine won't warm up during idling. Ok on second read though I get it. I would talk to your dealer, most of the time they don't want you to use grill blankets because it also blocks off cooling air flow to the intercooler, power steering cooler, trans cooler and so on. So it can void your warranty. I would check with them to make sure. You should not really need one but check with someone who can void your warranty to get GM's position.

Sure, not in the lines but the fuel in the tank. This is why you want a half tank or more because the flakes will settle to the bottom of the tank.

Should not be a problem unless you are using normal diesel or if the temps are consistently lower then 20F

Yes they add Kerosene to thin the wax to reduce solidification. The solid flakes are paraffin wax, same stuff as candle wax.

30F and lower but in most cases it is not necessary. I don't use additives at all and only plug the heaters in when I know I won't have enough time to let the engine warm up before I need to run. Most people get a good heavy duty electric timer and plug the block heater into the timer. At 30F you need to run the heater for 2 or 3 hrs and the time will increase as you get colder. At zero deg you should give it about 8 hrs or just leave it on all the time. I very rarely plug in my trucks and if I need to I just plug them in for 3 hrs before I leave. This works just fine for a 6.2 dsl and a Ford 7.3 power stroke. Never had either one not start or gel up on me here in the NJ/PA areas. Although at temps below 20 they really struggle. If you are constantly in the great lakes area or colder you may consider changing over the a diesel 10w30 engine oil. 15W40 has the consistency of thick shampoo at 20F...

The block heater will have nothing to do with the tank. As the fuel system send warm fuel back to the tank it will warm the diesel in the tank so just let the engine warm up. I have heard of a guy that worked in Alaska at one of the oil rigs. He used a small heating blanket/patch that he epoxied to the tank. Plug it in and it keeps the tank warm. But he was dealing with -40 or lower temps.

Yes, use winterized diesel, plug it in when possible, and use some type of fuel conditioner (like power service from walmart) and always let it warm up a little before you move off and don't panic unless you hear a noise the makes you spine hurt. And as always pay attention to the owners manual.

sure the most important thing is to be gentle when starting it when cold and give it some time to let it warm up. And remember diesels hate cold weather so you will hear some weird noises when starting when cold. One of the coolest things about the 6.2 was they would always start if you could get it turning. The service manual said 50 rpms at full throttle and it would fire.

Hope this helps, I don't own a 6.6 but in case no body answers you then you have some information from two guys with 6.2's.

mark

Add gasoline to the fuel. Check with Ford to see how much gas to add when filling with Diesel fuel. You can also diesel additive.

I live in The Netherlands and have been using a lot of diesels. Normally, I wouldn't worry for dieselwaxing if the temps are down to

-5C. At that time gasstations start to use winterdiesel. When making my own winterdiesel I added one liter of petroleum or kerosene to 100 liters of diesel.

The battery seems to be a bigger problem than the fuel, make sure you have a big fat battery which is not to old.

Timo

Dom wrote:

Most filling stations go to a 60/40 mix (diesel/kerosene) as soon as the cold weather comes. Make sure you got to stations that sell a lot of volome or you'll have Septembers fuel in December. Fuel gels when temps get to around 20 degrees. It will always gel at the narrowest part of your fuel line. The gelling is actually wax formations in the fuel itself. There are some good additives that prevent this as well. KD fuel supplement is one and CRC makes another good one. I run the CRC year round as it is also a conditioner. cleaner. As far as plugging in your block heater I put mine on as soon as the weather startes dipping below freezing. It is much easier on the engine/starter, and you will get instant cab heat. Beware these block heaters are not cheap to run electricity wise. Some people put them on timers(hot water heater timers) and have them come on two hours before they are to leave the house. This is plenty. Im in New England too and I have done this for years. Good luck Farmers Almanac calling for a ton of snow and bitter cold temps again like last year. Brrrrrr

Just one more item ...

Is it possible for me to be riding down the highway at 65mph, and my fuel lines freeze? What temp would that be at? (The truck doesn't know wind chill factor, does it?)

If the fuel lines do freeze, does the engine die at that point? I go into neutral, coast to the side and wait until I can heat the engine compartment up?

Thanks again,

Dom

Hi!

I don't know for sure, but I've never had it happen even in some very bitter winters. Make sure you have appropriately winterized Diesel fuel and you should be fine. You'll have to worry more about the fuel waxing than you will an actual freeze.

It would seem much more likely that the enigne would start to suffer from a lack of power and produce more smoke than normal before it actually died.

compartment

My own truck is very difficult to control if the engine is shut off (it has never just "died"). The front end is extremely heavy and when the power steering quits this becomes painfully evident. I also lose power brakes, and while I would hope that the manual brakes have perhaps improved over time, I wouldn't bet on it. My truck is difficult--if not near impossible--to stop when the power brakes fail.

William

Dom, I've had it happen on a semi with dual tanks and an exposed crossover line between them. The crossover line gelled up, effectively cutting my fuel capacity from 600 to 300 gallons. This was Idaho in February several years ago. Winter blend diesel fuel with no additives.

I'm not sure about the Duramax setup, but every other diesel I've owned pumped more fuel to the engine than was actually used. The excess was returned to the tank after being warmed slightly in the engine compartment, so the fuel in the tank and fuel lines is actually warmer than the ambient temperature (wind chill or not )

OTOH, it doesn't take much water in your fuel to freeze when it hits the fuel filter. I've had this happen in Missouri mid winter and it wasn't nearly as cold as the incident in Idaho. That WILL shut you down in a painful manner because it doesn't freeze sitting in the driveway, it takes a few miles and clogs the filter with ice at the most inconvenient point on your travels.

Greg

I do not think adding gasoline to diesel is a good idea, unless you want the diesel engine to suffer damage (lowers cetane rating of the diesel fuel). Use 1-D diesel fuel manufactured specifically for cold weather regions, or use diesel fuel additives specifically engineered to prevent gelling/paraffin separation, or use kerosene in a crunch but read the owner's manual first as to the maximum ratio allowable for the diesel pump/engine to operate safely (kerosene will lower the lubricity of the diesel fuel).

Add an in-line fuel filter (e.g., Racor 645) with the 12V heater option.