extreme cold and 300d's - PeachParts Mercedes-Benz Forum

texcl · #1 10-29-2013, 01:00 PM

It get's down into the -30's and -40's here and there will be weeks in the -20's. Will these mercedes diesels start without being plugged in if they are in good condition or is it a given that they won't. Also if they won't start in that cold, at what temp do they reliably start? There are plug ins in most places here but block heaters and plug ins fail. My old diesel dasher would start in -10 but not at -20. My 93 f-250 diesel won't start at 10, but it needs new batteries. My old TDI beetle would start at -30 but if you hit a chunk of ice on the road it would pop a hole in the oil pan (wife did it twice.) and was pretty bad in the snow since it was so low. I love old diesels but the whole extreme cold thing is a real caveat.

1project2many · #2 10-29-2013, 01:02 PM

Prolly better make sure you have the block heater installed and operational.

aieeegrunt · #3 10-29-2013, 01:04 PM

Making sure the valves are adjusted is a huge help on the old ones

texcl · #4 10-29-2013, 01:22 PM

yeah, I will install a new lower hose heater. I've had block heaters fail at really bad times and carry a magnetic heater to but it sorta sucks, not generating good heat. I try to get my diesels tuned where I can start them at -10 without a block heater, sometimes it can't be done. I'd like to hear from someone who has to deal with sub-zero weather on a daily basis like us to see how they fared.

JB3 · #5 10-29-2013, 01:42 PM

I was able to reliably start my 340k 300D at about -5 to -10 daily without a block heater during a cold snap while living in syracuse (think it went on for about a week to two weeks). Previously it would not start at any temp lower than 20F with 15w40, but I switched to 5w40 and it made a huge difference in cold starts.

I was cycling the glow plugs 5-6 times though before trying to fire every time. It would start first crank and sputter, but stay running, and id sit for 5 minutes and let it run

Zacharias · #6 10-29-2013, 09:31 PM

Quote:

Originally Posted by texcl

yeah, I will install a new lower hose heater. I've had block heaters fail at really bad times and carry a magnetic heater to but it sorta sucks, not generating good heat. I try to get my diesels tuned where I can start them at -10 without a block heater, sometimes it can't be done. I'd like to hear from someone who has to deal with sub-zero weather on a daily basis like us to see how they fared.

You say 300d, and I think everyone is answering assuming it's a w123, not a w124. Me too.

The only way to stack the deck in your favour at extreme low temps is to:

- have a reasonable amount of compression to start with
- have healthy and quality glowplugs (Bosch, NGK)
- adjust the valves
- have a strong battery (and keep it warm if possible)
- have a starter that's turning fast enough to start
- have synthetic oil in the crankcase
- add cold weather treatment, such as Diesel 911, to the tank before it gets really cold
- and get as much heat as you need to into the motor before you try to start, by whatever means available.

The way I see it, the more you move away from one of the above points being covered, the more you are relying on the others.

I have been driving these cars in Canadian winters in an area that has the distinction of being the second-coldest capital region in the world (after Ulan Bator, Mongolia) since 1997. I use a battery blanket or heating pad, a block heater and have just installed a lower rad hose heater as well. As of this year I now run synthetic year round, but prior to that ran it in the wintertime.

barry12345 · #7 10-29-2013, 09:46 PM

Good overall condition. I feel the 617 should start down to about zero or a little lower. The problem is the engines do not seem to enjoy that treatment nor the starter particularily.

Plug in a block heater when you can on cold nights. Put it on a timer to give the engine a couple of hours pre start heating time. Each engine will be a little different as they are so old and many have some deficiencies.

vstech · #8 10-29-2013, 10:04 PM

is there wind in the -30 to -40 nights? if so, in addition to the block heater, you should put a blanket around the motor... seriously. wind will draw away heat faster than the block heater can supply it if the radiator is in the breeze, and there is not blanket around the motor.

the fuel tank is INSIDE the car on the 123/124, so it's out of the wind, but it would still be a good idea to put a magnetic heater on the fuel tank.

DON"T USE DIESEL 911 unless you have water in your tank... it's NOT FOR COLD WEATHER!!! Power Service WHITE bottle is for cold weather. red has ALCOHOL in it, and it's bad for the fuel system. 911 is right... emergency water removal ONLY!!!

when I lived in SD, there were several winters well below -30... and if your battery was left out, and the block heater was not plugged in, no car would start. not diesel, not gasoline... ever seen frozen gasoline? not pretty.

perhaps investing in a webasto would be wise?

kerry · #9 10-29-2013, 10:15 PM

I've started my 85 300TD at 35 below zero fahrenheit without assistance of a block heater. I wouldn't recommend it as a regular practice. I usually plug in if temperatures are predicted to be below 5 degrees. I use antigel at those temperatures. You get one chance to start it at those temperatures. Second attempts almost always fail. Keep the starter cranking until a cylinder starts firing and keep the starter engaged until enough cylinders start firing to keep it running with your foot to the floor.

vstech · #10 10-29-2013, 10:31 PM

Quote:

Originally Posted by kerry

I've started my 85 300TD at 35 below zero fahrenheit without assistance of a block heater. I wouldn't recommend it as a regular practice. I usually plug in if temperatures are predicted to be below 5 degrees. I use antigel at those temperatures. You get one chance to start it at those temperatures. Second attempts almost always fail. Keep the starter cranking until a cylinder starts firing and keep the starter engaged until enough cylinders start firing to keep it running with your foot to the floor.

yup, the ONE AND ONLY TIME a diesel starter can be cranked extensively is in emergency situations when it's supremely cold like this. and just imagine the strain and damage this puts the starter in... a block heater, (NOT A HOSE HEATER) is the best prevention... keep the motor feeling like it's 60F outside, and the starter will last you a long time... crank it like this with supremely cold weather and no heat assistance, and you'll be changing that sucker much sooner than you'd like!
but if you are in this situation, you have to ignore ALL the advice you are remembering, and follow this one rule... you've got ONE shot at starting the car... ONE! so be sure you are totally ready and committed to the start attempt. glow the FULL 30-45 seconds depending on your controller and model car. WATCH THE DOME LIGHT FOR THE BRIGHTENING EFFECT when the relay clicks off IGNORE THE GLOW INDICATOR LIGHT IT"S USELESS FOR THIS!!! the instant the dome brightens, turn the key off and back on again to restart the glow cycle. do this at least 5 times, then on the last sequence, HIT THE STARTER, AND HOLD THE KEY ON UNTIL THE MOTOR IS RUNNING ON AT LEAST 3 CYLINDERS!!! and do not let the motor stall... keep your foot on the floor until the motor revs up indicating the other cylinders have fired.
next, wait for the oil pressure to build up then give it another 10 seconds or so, and go. do not let the motor idle, just GO! idling is NOT good for a diesel motor in the cold.

kerry · #11 10-29-2013, 10:40 PM

Not so sure about how hard it is on the starter. The MB handbook says to use it this way in cold weather. I've done it many times in the 10 yrs I've owned my TD and the original starter is still spinning away.

whunter · #12 10-30-2013, 12:22 AM

Quote:

Originally Posted by texcl

It get's down into the -30's and -40's here and there will be weeks in the -20's. Will these mercedes diesels start without being plugged in if they are in good condition or is it a given that they won't. Also if they won't start in that cold, at what temp do they reliably start? There are plug ins in most places here but block heaters and plug ins fail. My old diesel dasher would start in -10 but not at -20. My 93 f-250 diesel won't start at 10, but it needs new batteries. My old TDI beetle would start at -30 but if you hit a chunk of ice on the road it would pop a hole in the oil pan (wife did it twice.) and was pretty bad in the snow since it was so low. I love old diesels but the whole extreme cold thing is a real caveat.

My best extreme low temperature suggestions are:

#1. Synthetic 0W40 engine oil...................

#2. Replace the glow plugs if they are even slightly less than PERFECT.

#3. Keep the valves adjusted.

#4. Test the charging circuit, and replace the voltage regulator if it is less than PERFECT.

#5. Check the battery date, if it is over four years old Replace it, carry a second battery in the trunk or find a way to mount 2 in the engine compartment.

#6. Replace the battery cable ends with automotive battery quick connect terminals, so you can carry it inside at night.

#7. Replace the starter with a gear reduction unit = double your cranking speed.

#8. Add 1 - 2 gallons of kerosene to the tank at every fueling.

#9. Carry a case of Sterno canned heat, it can cook engine oil up to nice starting temperature, and may save your life in a blizzard = one case is 24 hours of continuous heat or longer depending on your need.

Sterno Non Toxic Biodegradable Chafer Buffet Heating Cooking Fuel 6 Pack | eBay

#10. Move to the tropics.

These are nice if you can buy or build a metal belly pan MB# 1235200342 for road ice impact.

Hot Pad Heater Engine Block Diesel Truck Cold Oil Start Winter | eBay

Here are more of the best answers, covering many years and vast experience of forum members.

Cold weather starting links

http://www.peachparts.com/shopforum/diesel-discussion/85227-engine-heater-ideas.html

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texcl · #13 10-30-2013, 08:13 PM

It would only be started without the block heater in emergencies, since becoming a diesel fanatic I have had a couple of these emergencies, once when my block heater failed and a couple times when the plug in failed. It really sucks being stuck at work because your car is frozen at least we have enough supplies at work to survive a few days. The worse is being stuck in a car that broke down in sub-zero weather, it's down right scary.

Graham · #14 10-30-2013, 09:02 PM

Quote:

Originally Posted by texcl

It would only be started without the block heater in emergencies, since becoming a diesel fanatic I have had a couple of these emergencies, once when my block heater failed and a couple times when the plug in failed. It really sucks being stuck at work because your car is frozen at least we have enough supplies at work to survive a few days. The worse is being stuck in a car that broke down in sub-zero weather, it's down right scary.

Tex,
You asked for people with experience. Well, I have owned my 85 300D for 23 years and when I was working, it was my daily driver. This in Eastern Ontario, Canada where it is not as cold as your area, but still pretty cold at times!

I would agree with everything Zach wrote and he is in a colder part of Ontario than I am. Don't want to start an oil war, but I don't use 0W40 on my 300D. It is aimed at newer cars. For our old diesels, I would rather use Mobil 1 Turbo Diesel Truck 5W40.

Overnight, you need to park indoors, if you can. Or at very least have a working block heater plugged in any time temperature is below freezing and even higher. Even indoors, you should use the block heater (on a timer) although I have got by with a magnetic heater recently. I need a new heater cable! I sometimes would supplement block heater with a 100 watt light bulb under hood and if it was really bad, drape a small tarp over car and even run an electric heater under engine for an hour or so.

During day, I usually had to leave car exposed to frigid weather all day with no heater. On very cold days, I would go out at lunch time, start engine and perhaps go for short drive. Nevertheless, I had a few occasions when car would not start at all and I had to get towed. This with a well maintained car with everything up to snuff.

I never modified car in any way. Still has original starter. But I did always buy the biggest battery with maximum cold cranking amp rating. This explains CCA

I wouldn't even think about not having a block heater for any temperature below freezing. These are not good winter cars!

Brian Carlton · #15 10-30-2013, 11:58 PM

Quote:

Originally Posted by vstech

yup, the ONE AND ONLY TIME a diesel starter can be cranked extensively is in emergency situations when it's supremely cold like this. and just imagine the strain and damage this puts the starter in

When you change delivery valve seals on a 603 and need to crank it for 120 seconds total time, you'll realize how erroneous the above statement is.

Also, holding the engine at a fast idle (1000 rpm) for a few minutes does wonders for driveability. Using your advice and immediately driving away in the bitter cold is a royal PITA because of the very low power levels available.