Gelled Diesel: How do I fix this?
 

A couple of nights ago the temperature dropped below zero and stayed that way until today. After that first night, my 1981 300D wouldn't start in the morning. It's hooked up to a block heater, but it doesn't seem to be doing much, as the car still won't start (actually won't even turn over:(). What does this mean and how can I fix it?

Thank you all!

How do you know the diesel is gelled? Where are you located and where did you get the fuel from? Around here, diesel from the pump is good down to -30F.

Me thinks the problem lies elsewhere. How are the glow plugs?

I'm located in Jackson, MI. I suppose I assumed it was the diesel gelling because I've always heard it tends to do so quite easily and I've read other posts about people with various diesel cars experiencing the same problems (no turning over after a cold night) and figured this was likely the problem as the car was running fine the day of that first cold night, but not the next morning.

If your engine isn't even turning over then you have an issue other than a fuel issue. Is the engine trying to start and just not catching or is it not even turning over.
If you do have a gel problem generally the filter is where gelled fuel will cause an issue. A new filter might solve the issue.

The engine isn't turning over at all. I've had problems nearly identical to this before when it's been cold out, where the engine will try to start but won't catch. Overtime as I would continue to try to start the engine, it would make less and less of an effort, until it wouldn't even turn over, just like now. In the past, plugging the block heater in has always fixed this problem, so I assumed it had something to do with the fuel.

If it won't crank/turn-over, the battery is the first problem. Charge or replace your battery. If it won't stay charged or won't charge from driving, you have electrical problems.

Fuel here in Michigan is fine at 0F, it has been well above that during the day also, so I doubt that is your problem.

Diesels fire from the heat of compression. The faster you crank, the more heat it produces and the more likely to start. Bad starter/battery/alternator/wiring can all contribute to slow cranking and that will often result in a no-start when it's cold.

Synthetic oil also helps in the winter as it allows the engine to crank more easily, and the block heater will help with heat and cranking speed.

I just recently replaced the battery. Is it possible for the battery to freeze or something of the sort? I'm just thinking outloud.

Batteries are just a chemical reaction. Lower the temperature and you lower the power output of the battery.
In cold weather you have many things working against you. Lower power from battery, viscous oil, lower combustion chamber temp. All these things make it difficult to start. I would start by putting a charger on your battery. Once charged, if it still won't turn over, take it to a parts place and have them test it.

Possible semantics problem here
 

I've noticed lots of car people have a different idea of what "turn over" means. To me if the starter motor is rotating the crankshaft the engine is turning over. But to some guys "won't turn over" means the fuel isn't exploding and the engine isn't starting to catch and run on its own.

It makes a big difference in troubleshooting, 'cause in one case it's a battery/cables/starter issue, in the other case a possible glow plug/air in lines problem.

Your owners manual says to add kerosene to prevent gelling.

Danny

X2.

We go off on tangents all the time because proper terminology of "won't crank" and "cranks but won't start" is not utilized.

"Turn over" has proper usage as well...........but not on a vehicle.:D

The manner in which im using the word (not sure if it's the appropiate one) refers to the engine not doing anything when I attempt to start her up. All that happens is a little "click".

Mmmm turnover.

That would be a dead battery or a bad starter. Not gelled diesel. We have winter diesel here in MI, good to down around -25F or so.

Not to winter blend diesel, only #2 diesel which you can't find in any northern states in the fall/winter.

Not gelled fuel. In fact there are a number of threads here on this problem in cold weather. It is often related to poor connections in the ignition circuit. There is a junction box on top of the passenger inner fender in front of the battery. Glow the plugs, then jump terminals 1 and 3 in that junction box. Your starter will most likely engage. If it doesn't, report back.

have you tried starting it in Neutral?

If it were a bad NSS, you wouldn't get a 'click" (I believe).

Ok, now I've seen everything with this car. I went to pop the hood and upon pulling the lever that pops the hood, I felt a slight electrical current buzing through my fingertips. I figured I was just crazy and continued about my business. However, as I went to lift up the hood by grabbing the grill, I got another nasty shock. I have no idea what this means, or if it's even related, but I figure someone might?

Was your block heater plugged in? If so, sounds like a short in the block heater circuit and thats what is giving you your shock. Just a thought, I'm no expert:confused:

First thing to check is the battery cables. See if they are tight on both ends and clean on the battery.

Will the horn or lights work? If not then the fault is the battery....

The block heater is shot or wiring is shorted if you got a shock from the car. I've had this before.

I have never seen gelled fuel yet. This winter was nasty in Chicago and I had some diesel fuel in plastic bottle in my trunk just to see what it becomes at -10F. Still nice and liquid...

Unplug the blockheater and see if you still get shocked. My guess is the block heater is shorting out and not heating your engine block. Plug it back in and see if the shock comes back.

the solenoid wont click, but there is a relay or two behind the dash that'll click. some peeps may not know the difference.
I dont really think it's the NSS, but lets eliminate in anyways. it doesn't cost nothing to try to start it in N.

Yep, you're right.

Sounds to me like you need to charge your battery. That would give you a click. Do that first. If that doesn't help then it is something with the wiring/starter. When mine was clicking the wiring to the starter was loose.

Unplug the block heater and see if you still get shocked. If you don't then it obviously is the block heater causing the shock. :sun1:

You need to do a little research on cold weather starting.
Here is a checklist of things that can cause problems in cold weather, thus preventing the car to start.
Glow Plugs
Battery
Starter
Oil Weight
Fuel
Compression

Thank you for the advice everyone. Things have been crazy around here, so I haven't got to do much in the way of trying to fix this bad boy. I plan on testing all the areas you folks are mentioning (glow plugs, battery, etc.)

I tried starting her in neutral for kicks, but no luck.

I know how to test the battery (trying the heat, radio, lights, etc.), but what else can I do to test the other areas?

Thank you all so much. It's a little nerve-wrecking being a first time owner sometimes (especially when you don't know anything about cars:o).

I just tested the battery by trying the radio, lights, turn signal, heat, etc. and all work just fine. Just though I'd let everyone know!

That doesn't tell you whether the battery and/or its connections are good enough to carry the load necessary to operate the starter. Only a load test will confirm the health of the battery. Usually if the battery connections are poor, when the 'click' occurs, the battery disconnects and the idiot lights go out until the connection is re-established.

That doesn't mean there is enough juice to run the starter. You can get accessories that take little draw from the battery to work but major ones (like the starter and glow plugs) not to work. It may be is something else, but what you did doesn't eliminate a low charge on the battery as a contributor.

I would still charge the battery or try to jump it. When you try to start it next (and get the starter spinning) let the glow plugs go for 30 seconds before you try starting it.

Run a glow cycle and look at the dome light, if it fades away to nothing while glowing or cranking then your battery is shot.

Tried jumping the battery, no luck. Planning on trying to run a glow cycle and connecting terminals 1 and 3 tomorrow to charge the starter.

what? Charge the starter? I am not familiar with what you are planning here.

When you tried jumping it, did the clamps spark when you connected them?
They will only spark when they are transferring current. If the battery is fully charged when you connect, no spark. If the battery is drawn down, then they will spark. Do you have a volt meter? Real good tool for this kind of issue. My guess is that you have a weak/dead battery. Even if you just replaced it, doesn't make it good. For a car to suddenly not crank when the temperature drops is nearly always a bad battery. If it is recently replaced, then you most likely have a problem in your charging system, although it is not unheard of to get a defective battery, depending on what and where you bought. Check for loose wires on the battery, on the alternator, and on the starter. Starter could also be an issue, drawing too much current, then when the cold strikes and your battery loses some of it's cold cranking amps, it can't overcome the impedence of the starter.
First thing I would do if I did not have a meter would be to actually switch the battery with one that I knew was good. (ie from a different vehicle)
If the car starts, then you know that the battery is at least part of your problem. If it doesn't, then you can move to the next step.

Tested the battery with a meter and it is working exactly as it should. I tried connecting the 1st and 3rd terminals in the junction box on the passenger side terminal and then running a glow cycle, but nothing.:(

I'm new to diesel engines-save for a forklift and a garbage truck I drove for 3 years, so I have to ask....What is diesel fuel gelling mean? I have never hear that phrase before. Is it like when gas turn to varnish? How long does diesel last before going bad?

And please nobody reply, "Don't ask me, I'm just gellin!" >.<

You have the process reversed. Glow, then connect 1 and 3. When you connect them the starter should turn over. Did it spark when you connected them? Do you have voltage at 1 or 3?

When you say you tested the battery with a meter, what do you mean? You have to load test a battery to tell if it has enough power to work the starter. A voltage meter won't tell you, although if it reads 5 volts, it's not going to work. But a battery with 12 volts is not necessarily a battery with enough power to turn the engine over.

Gelling means the fuel turns from a liquid to a solid. #2 diesel, with no additives will start gelling around 0 or so I think.

VICTORY! Tried tapping the solenoid with a hammer and wah-la! Thank you everyone.

The reason you have never heard about it is because it is something you don't have to worry about in Texas.

When it gets really cold, diesel fuel starts to cloud up and solidify. This is what 'gelling' means.

Here ya go -- some good basic informaiton and terminology for Diesel:

#'s 6, 7, 11, 17 & 18 are good info for this topic...

1. BIOCIDES killor inhibit microorganism growth and prevent the effects of microbiological growth. Serious problems that can arise from microbiological proliferation are: sludge formation, acid andsurfactant formation with subsequent water entrainment and fuel filter, screen, and line plugging.

2. BLENDED DIESEL FUEL is one that combines #1 diesel fuel (i.e. kerosene) with #2 diesel fuel. The ratio of diesel fuel to kerosene is typically found in the range of 80:20, 70:30, 60:40, or 50:50. See "Kerosene Blended Diesel Fuel" under Resources for additional information.

3. BRITISH THERMAL UNIT is a measure of the energy content of diesel fuel. Technically, a British Thermal Unit is the amount of heat required to raise the temperature of 1 lb. (0.4 kg) of water 1°F. Diesel fuel that has a higher BTU content will experience an increase in engine power and fuel economy.

4. CETANE IMPROVERS increase the cetane number of diesel fuel. Cetane number is the most universally accepted measure of the ignition quality of diesel fuel. Proper ignition during the combustion cycle is essential to optimum operation, economics, and durability.

5. CLOUD POINT is the temperature at which wax crystals in diesel fuel begin to form and the fuel goes from a clear appearance to a cloudy appearance. See Pour Point.

6. COLD FILTER PLUGGING POINT (CFPP) is a test to evaluate the effectiveness of diesel fuel additives in improving winter fuel operability. The CFPP test involves pulling a determined amount of fuel through a fuel filter in a given amount of time. The temperature is dropped in small increments and when the fuel fails to pass through the fuel filter in the given amount of time it fails the test.

7. COLD FLOW IMPROVERS are designed to depress the cold temperature operability limit of diesel fuel. Cold flow improvers modify the size and shape of wax crystals that form as the fuel is cooled below the cloud point. Crystals in untreated fuel have relatively large flat structures and tend to stick to one another to form a lattice structure or gel. The crystallization of wax in diesel fuel causes waxing/gelling. Cold flow improvers reduce the crystal size to 1/10 or less of the size of untreated crystals to reduce waxing/gelling.

8. COMBUSTION IMPROVERS increase fuel economy through improved combustion efficiency and/or reduce diesel exhaust emissions and smoke.

9. CORROSION INHIBITORS prevent oxidation (rust) on metallic surfaces due to moisture and acids.Corrosion inhibitors can protect against two of the three types of corrosion, typical oxidation on metallic surfaces due to moisture and internal corrosion of injectors. Microbial induced corrosion may not be addressed by typical corrosion inhibitors. See Biocides for more information on microbial induced corrosion.

10. CUMMINS L-10 INJECTOR DEPOSIT TEST is used to evaluate the effectiveness of diesel fuel additives in improving fuel injector performance. The test consists of configuring two Cummins L10 engines in tandem, connected by a drive shaft. For 125 hours, the engines alternate from power to idle in 15-second intervals, one engine pulling the other for 15 seconds, and then reversing roles. To pass, two criteria must be met. First, there must be a flow loss of less than six percent. Flow loss indicates a loss of power from a dirty injection system. Second, there must be a CRC Rating of 10 or less. The injectors are disassembled and the carbon build-up is visually rated by a trained technician. The technician assigns a numerical score of 1 to 40 with 1 indicating a new/clean injector and 40 indicating a very dirty injector. To pass the Cummins L10 test, all six injectors must have an average CRC Rating of 10 or less.

11. DEICERS reduce the freeze point of water that may separate from the fuel or disperse the water in such small droplets that ice crystal formation is precluded or inhibited.

12. DETERGENTS/DISPERSANTS prevent deposit formation or remove preformed deposits in the combustion chamber and on injector parts. Detergent/dispersant benefits include improved fuel economy, increased engine life, increased fuel system and fuel filter life, and reduced exhaust emissions and smoke.

13. DIESEL FUEL is principally a blend of petroleum-derived compounds called middle distillates, which are heavier than gasoline but lighter than lube oil. Diesel fuel is combustible and used for fuel in diesel engines.

14. DIESEL FUEL ADDITIVE isa chemical added to diesel fuel to enhance one or more of its properties.

15. EMULSIFIERS chemically react one liquid with another liquid. An emulsion is a suspension of one substance in another substance. Emulsifiers have the ability to remove water from diesel fuel and do not allow water to settle out.

16. FLASH POINT isthe temperature at which a liquid will yield enough flammable vapor to ignite.

17. GELLING/WAXING is a thickening of diesel fuel caused by wax crystals which form as the temperature of the fuel is reduced. Gelled/waxed diesel fuel is difficult or impossible to pump and will plug fuel filters, preventing fuel from reaching the engine.

18. ICING isthe formation of ice crystals in diesel fuel caused by free water within the fuel. Icing occurs whendiesel fuel is cooled to 32°F or below. Ice crystals will plug filters in the same manner as wax crystals. See Gelling/Waxing.

19. KEROSENE isa class of middle distillate diesel fuel used for blending winter diesel fuel. Kerosene is also referred to as #1 diesel fuel. See "Kerosene Blended Diesel Fuel" under Resources for additional information.

20. LOW SULFUR DIESEL FUEL FEDERAL SPECIFICATION
a. Dates: 1994-2006
b. Sulfur Content: 500 ppm Maximum
c. Cetane Rating: 40 Minimum
d. Percent Aromatics:35% Maximum
e. Note: For important changes currently in effect, see Ultra Low Sulfur Diesel.

21. LUBRICITY refers to the ability of a fluid to reduce the friction and wear between two moving surfaces. Diesel fuel lubricity refers to the ability of diesel fuel to prevent wear on contacting solid surfaces found in fuel pumps and injectors.

22. LUBRICITY IMPROVERS protect against wear of the engine fuel system (e.g., injection pump, injectors, etc.) by forming a protective layer on metal surfaces. Lubricity improvers prolong the life of critical wear parts in the fuel system, reduce downtime, and reduce maintenance costs.

23. POUR POINT is the temperature at which diesel fuel will no longer flow. The difference between the cloud point and the pour point is generally from 0°F to 15°F.

24. STABILITY IMPROVERS prevent fuel degradation by preventing various reactions. Stability improvers prevent fuel from degrading and eliminate gum deposits from forming in the fuel filter and on engine components.

25. THERMAL STABILITY refers to the ability of diesel fuel to maintain its chemical properties at high temperatures. Thermal stress (high temperatures) can cause diesel fuel to degrade and form insoluble materials that can restrict fuel flow through fuel filters and injection systems.

26. ULTRA LOW SULFUR DIESEL FEDERAL SPECIFICATION
a. Dates: 2006 - Present
b. Sulfur Content: 15 ppm Maximum
c. Cetane Rating: 40 Minimum
d. Percent Aromatics: 35% Maximum

Lot's of good reading there, but it doesn't mention home heating fuel, my car's favorite food.
Same as #2 diesel from the pump, just without the dye and taxes.
That and they deliver.

Not true. Heating oil is not tested for cetane, it may or may not be 40 or above. Heating oil also has no lubricity spec. It may or may not lubricate as well as diesel. Diesel meets all of the specs for heating oil but not the other way around.

It may run just fine in an old MB, but it is not the same thing.

Plus there could be hefty fines in your state like there is in mine for the use of non highway fuel over the highways. Here in Washington State we have one of the highest gas taxes in the nation and if you get caught under law prescribed in R.C.W. you are punishable by up to a $10,000 fine

yuk!

The fact that it worked after hitting the starter points to a worn out starter but it is not conclusive. Others have found that increasing voltage or amperage to the starter by putting a solenoid relay in the system, stops this kind of problem so it is still possible that the existing wiring is old enough with poor enough connections to reduce power to the starter and your hitting the starter allowed it to get better enough connections to function with the reduced energy. I only point this out because some people have replaced their starters only to have the problem continue. If you are certain that there was power when you crossed terminal 1 and 3 and the starter still did not turn, this would point even more at a sticky solenoid or bad starter.

Also doesn't explain the alternator & battery problems mentioned.

Check the ground strap to the engine.

He said...


"VICTORY! Tried tapping the solenoid with a hammer and wah-la! Thank you everyone."

GWB also said mission accomplished.

... and as Kerry said, it is not conclusive, so no "wah-la" (viola).

Wrong thread on the alternator though (sorry).