Cold Start Question
 

83 300CD
Hit -10F last night, it's only 6F now. The car started yesterday at 5F with a little patience but won't start today. I've just plugged in the block heater, don't know if it works. Charging the batt to to help warm it up a little. Are the any other SAFE things to try to get it running? Is spray start dangerous with a diesel, i.e. do I risk blowing the head gasket? Should I just kick back for an hour and let the heater do its thing? I'm thinking the hood pad insulates this motor so well, it still thinks its -10. The hood pad looks nice but the snow never melts!

Thanks

My block heater makes a hissing noise kinda like an electric kettle just seconds after it's plugged in (if the engine is cold). The top rad hose is warm after an hour or so . I've heard never to use 'starting aids' on the MB diesel because of the pre-chamber design. The battery has to be in great condition once the temps start to drop. I have cranked mine for up to 30 seconds to get it going when my GP relay was hooped. I usually use the block heater for 3-4 hours before starting, have it on a timer.

had a neighbor that would bring pans of hot water outside and pour over his engine. I thought he would crack something but never did. Later he started putting an electric space heater in the engine compartment. He was very proud of this set up. Told all the neighbors of his genious idea. I'm glad he never had a fuel leak (gasoline).

If your block heater is working, it should solve the problem. 11 below in Denver this past week and the block heater worked nicely on the 77 300d. You could also try blowing a heat gun or hair dryer into the intake as you try to start it. A propane torch is also an option.
Another alternative is just to take a taxi and wait until it gets warmer. It's not worth putting a lot of work into it at that temperature.

You could also try blowing a heat gun or hair dryer into the intake as you try to start it. A propane torch is also an option.

Wow! Even double WOW!! And if that doesn’t work how about a phosphorus grenade shoved down the fuel tank? Now that will be sure to get something going!

Geeze!

You write as though the suggestion is unusual. Some older diesels were designed to be started by a fire in the intake system. I think some modern diesels also use a similar system

My Cummins engine actually has two rather large electric heating screens in the intake manifold that act just like a hairdryer or propane torch would. Glow plugs aren't really all that much different either--just smaller and more cylinder specific versions of that hairdryer...

rmmagow,

did you get it to fire?

a nice drive upto sturbridge mass to the gtg today would get it warmed up nicely
:D

Kerry,

I tried the hair drier trick up at Tahoe once without much success. I thought as I'm sure you did that I could help the air temp in the combustion chamber get up to the 900* required for ignition. I don't have much need for cold weather starting tricks in the Bay Area. I only need help if I take my 83 wagon up to Tahoe to ski. I'll be going up for a weekend here soon so I might try a heat gun which puts out way more heat than a hair drier. A friend who has had a lot of cold weather experience says that synthetic oil makes the difference. I wouldn't normally waste my money on synthetic oil, but I may put it in on this oil change coming up to see how it does at high altitudes and cold temps.

Peter

The "thermostart" system used in some diesel tractors places an element in the intake manifold that looks something like a cigarette lighter element.

Power is applied to that element to make it glow red hot, then diesel fuel is slowly dripped onto the element and burns.

Works quite well - glow plugs not required.

Ken300D

Since part of the original question was never answered.... You should NEVER use starting fluid (ether) in a diesel with glow plugs. The glow plugs run from 900-1100*F and could ignite the starting fluid, not a good thing.... While I'd be hesitant on using it on a normal diesel some like my dad's backhoe has "ether injection" system built in from the factory, but it also does NOT have glow plugs! I heard spray oil works as a less harsh starting fluid but still shouldn't be used with GPs.

Car is starting on first glowplug burn at -5F with the block heater plugged in all night. Guess that's what the things for :o
At work, I go out at lunch and drive it a few blocks to keep it startable, Probably over-doing it but who the hell wants to screw around with jumper cables at night and at 0 degrees.

I have a set of jumper cables in my trunk... and I hope I'll never have to use them. :D

All night is a bit much isn't it? Mine made a world of difference in 45mins near that same temperature, if you want to be safe double that and add some. So if you got a timer set for 2hrs it should be fine but use 1/4 of the electricity. (saving 42kw-hrs per week assuming 1kw which it is probably a little higher.) Just for the sole purpose of never wearing the heater out I'd consider it, ever hear how much fun it is to break that plug loose after 25 years...?

the way it's been out here i think that you need at least 3 solid hours plugged into the block heater to make a difference. i plugged in this a.m. (about +2 deg F ) for about 1.5 hours after sitting all night unplugged and it started 1st crack but took twice as many revolutions of the starter to fire up.
also the warmup time was greatly increased. took about 40 minutes on the highway (at 70-80 mph) to get the temp needle barely past 80.

the other day at a lower temperature i plugged for 4 hours and it was much easier for the initial start and quicker warmup.

While I think 3-4hours is a little excessive for 0+ temperatures, that would still save about 120kw-hrs a month!