6CTA8.3 Cold Weather Starting

[dodgemain]

Hi,
I had a question in reguards to starting my M929A2 in the cold weather. Now that the weather is in the 40's or 50's. It seems to be starting differently than in the summer. All summer the truck would start right up. Now in the cooler weather when it starts it seems to idle low for a several seconds then slowly the engines RPM's rise. During this time there is little throttle response. Does this sound normal? How should this engine behave in the cooler weather? Or, how should I be starting it?
Thanks

 

[CanonNinja]

Sounds about like this one:

[media]http://www.youtube.com/watch?v=lXN4Co5ZCFU&feature=related[/media]

 

[dodgemain]

Sounds about like this one:

Mine does not start that rough. That's one funny video clip.

 

[dk8019]

Dear Lord! Is something wrong with that truck? Not a single one of mine has ever taken that long to start, even when it's been cold outside. Someone needs to tell the guy to lay off the throttle when starting it as well!

 

[mudguppy]

i don't know if the 6C's use a grid heater like the 6B's do. do you have any kind of manifold heater or cold start switch?

 

[WillWagner]

The "C's" do have flame heaters but not on the aftercooled engines in the 900 series trucks. If it were charge air cooled, it would.
The throttle should still be there even in cold weather. There could be issues with the overflow valve or the fuel shut off not pulling up all the way.

 

[BKubu]

I have owned quite a few M939A2s and I never had any difficulty starting them in cold weather and I never noticed any unnusual sounds. I usually hit it with just a tad of starting fluid while I am cranking and it starts up all the time no matter the temperature. Admittedly, it does not get as cold in MD as in MI, but I have started it in the 12-16 degree range without any trouble.

 

[Earth]

As a life-long starter of diesels in cold weather, rest assured that some react differently than others to cold temps. I had an old JD 2440 that needed some quality time with the block heater anything below 50 degrees. With some heat it started awesome. On a cold morning recently, (18 degrees), I had one deuce fire right up, and one that didn't. They both have good batteries and start great in warm weather. One just needs heat when its cold, the other one will need heat when its even colder. Balking at a cold start doesn't mean anything is wrong.

 

[Blood_of_Tyrants]

What you must remember is that the fuel in a diesel is ignited by compressing the air to the point where it is hot enough to ignite the fuel. If the block is cold, it can actually absorb the heat in the compressed air to the point it isn't warm enough to ignite the fuel. Quick and easy fix, hit it with a shot of ether. The ether will usually warm up the cylinder enough so that the block won't absorb too much heat to ignite the diesel.

 

[dodgemain]

Thanks for all the great information. But, what is the correct way to start and harm up a 6CTA8.3 or NHC 250? Is the operator manual correct? When the engine starts cranking should I be pressing down on the gas pedal? Thanks

 

[dk8019]

That's a good point, my dash plate says something to that effect as well. All the talk a few weeks ago about keeping RPMs down when starting had me thinking that it was a bad idea.

 

[Earth]

The best thing to do is to warm up the block. Lots of ways to accomplish this, but it really works. Air temps from cool to minus 30, a warm block will start right up. That's how we handle the tractors anyways. No ether, no cranking away on starters, no pistons asked to start when the steel is icy cold and the oil puddin-like.

Just my 2 cents