Umm, a little help?? ALASKA, cold starting -55 Farenhiet in the winter
 

Ok, so where I live it gets down to -55 Farenhiet in the winter. My car will barely start at 20, after being plugged in for two hours and with a 200amp starting booster. Do I need to clean the carbon out of the motor and clean the injectors??? I have a brand new Gear Reduction starter on it. Please help!

First get the glowplugs working then take it from there.

Glow plugs must be working for reliable starts for sure but also you can:
check battery
check battery cables
check fuel filters
run biocide in tank
check air filter.
check compression if low
adjust valves
if still low a rebuild might be needed.

I thought you were joking about living in North Pole, Alaska, but I looked at Google Maps and sure enough, the town of North Pole is SE of Fairbanks.

For starters, (no pun intended) I would use synthetic oil. And the thinnest viscosity recommended in the owner's manual. There is a temperature chart in the manual. I do not have mine with me or I would make a recommendation.

If there are any diesel shops in Fairbanks, I would talk to the folks there. They should have some practical advice.

At -55 F you are going to want everything working in optimal condition. Glow plugs, injectors, good fuel. You might want to thin out your diesel fuel with some kerosene.

How many miles are on your car?

I'd agree with running some mix of kero in there with the diesel.

Welcome aboard and if you see Santa tell em I said thanks for the socks I got this past Christmas:).

Is this the car's first winter in Alaska?

I would be concerned that the car might not fully warm up at that temp, I know the big trucker guys like to block off their radiators with a WELL SECURED piece of cardboard or tarp or something of the sort. I like the idea of finding a diesel shop and talking to them - they will definitely know the "tricks" of the climate. As for the glow plugs, oil, etc...good advice.

The basics outlined by others are necessary to start at 20 on down to, say 0 deg F: fresh glowplugs, clean filters, healthy battery, valves properly adjusted. The low extreme you are talking about is severe service. I'm not sure if Mercedes even did product development testing down to that low a temperature on its cars.

Someone else asked how many miles are on your car. I would call the Canadian philosophy something like this: the more miles, the less compression you may have, the more heat you have to introduce to compensate.

How long does it stay down around -55 at a stretch?

Frankly at those temps I would consider just leaving the car running, never shut it down. That is what I understand is the general practice with diesel equipment in far-north situations like this. I do grant you that the Mercedes diesels aren't purpose-designed to idle for long periods, like some equipment diesel powerplants, but at that temp the startups are likely to be as damaging as any side-effects from extended idling.

Otherwise you are going to need a massive amount of auxiliary heat going into the motor prior to cranking at -55. I would suggest a block heater AND some form of coolant heater in use at the same time, and possibly even a low-power inline fuel heater under the hood (these are common in Europe -- not the heaters sold for vegoil cars, those are too hot).

And a battery blanket.

In my experience, you need to have the block heater (and/or other heat sources) active for at least four hours at regular winter temps, prior to startup. At -55 you would need to leave them on anytime the car wasn't going to be restarted within two or three hours.

This would be in addition to the other advice given already on valve adjustment, kerosene, grille covers, synthetic, fresh glowplugs, etc....

The coldest I've ever started a Mercedes at was my '79 300sd at -37 deg C (-35 F), with a battery blanket and a circulating coolant heater.

Ok
 

Well, I have brand new Bosch glow-plugs in it. I bought them in September, and hardly noticed a difference in the rough starting. I have no idea on the mileage. Odometer says 104,xxx but doesn't work. I don't plan on driving it when it gets to be -30 but would still be nice if it would start. I have Amsoil Diesel Synthetic oil in it. 5W 30 I believe. Was $14 a quart! I want to get a carbon reamer for the glowplug holes. I ran a can of Seafoam through in September, but didn't make a difference. Any ideas for decarbonising the motor? Something to mix with the fuel would be best. Thanks a bunch!!

You need to test the glow plug system to make sure it is working. You need to check the voltage to the plugs with the key in the glow position and the resistance of the plugs.

Do you park your car in a garage at night?

If you're not in a garage that you can keep warm and you trust the area
where you leave your car overnight, lock it up and let it run all night long.
You won't use much fuel just idling all night long. I've been in -40 weather
before and that was the only way to keep our gasser running.

What do other people in your area do?

Jeff

x2. if you are having trouble starting it at 20F with two hours of block heat you either have disfuncitonal glows or low compression. It is my understanding that testing glows with them in the block is not reliable.

You asked for a little help and here it is. You need to be sure your glow plugs work before you try anything else. Several people have correctly said it was a glow plug problem from your description and you seemingly refuse the advise

FYI
 

The OM617 in arctic condition testing for the military.


http://www.peachparts.com/shopforum/diesel-discussion/244785-240d-motor-snow-cat.html

BV-206 - Wikipedia

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