Sounds like the intake grid heater isn't doing its job. Mine wasn't starting well last year, so I check mine and found I was only getting about 3 volts to the grid heater. Cleaned my connections and all is well. My voltmeter in the truck now drops by several volts when the grid kicks in, before it was only dropping about 1/2 volt.
check you batteries first it needs to crank fast . also step on the throttle a little see if that helps . could also be your starter . and make sure your not getting air in the fuel system . mine will start with out waiting for the grids to kick in even when its in the 20s
- Intake heaters are malfunctioning
- Fuel is gelling (or beginning to)
- Fuel filter is begging to be changed
Down yonder in the deep south, your fuel probably has no anti-gel in it. Since that's the temp where #2 starts to crystallize, you could be on the ragged edge. You might ponder keeping a small supply of emergency anti-gel on hand for these occasions.
What do you mean it doesn't start ? Needs good spin up, probably the batteries.
Do you plug in the block heater at night?
Floyd
I know that the Cummins are excellent in the cold for starting. It dropped just below freezing last night and this morning my truck struggled to start. It did finally but took several minutes. The last time it did this was when it dropped below 20 degrees last year.
Where to start?
I added Seafoam to my tank last fill up and finally put a few miles on today.
My fuel filter is not that old... still several thousand miles from changing. Good thought though, I may change it just in case.
Your Cummins will spin up much faster and blow less white smoke if you switch to synthetic oil. This made a huge difference for me. I get easy starts down to 10 degrees and if it's colder than that I cycle the grid heaters twice and it starts right up. With the dino oil it would buck and shake and blow white smoke at 10 degrees; now it runs smooth at startup. I never use the engine heater.
Go to a good syn and run it year round.
I run dino oil in my Mule and Freightliner (Moose) and have no trouble with then firing up in cold weather (30 F to 28 F).
I have read post on hard starting in cold weather it turned out to be a lift pump. I woud do a fuel pressure test on the lift pump after the filter make sure you are getting at least 20 psi at idle. Rev the engine to 2000 and see if the pressure goes up.
Chris,
I have never owned and don't have any experience at all with 12 valves. They may have different characteristics.
I had to start my old '01 once when it had over 300k miles on it when the ambient temperature was -20*F. That's minus 20 degrees. I was transporting and spent an extremely cold night in a Motel 6, in western Nebraska if I remember correctly, might have been the Dakotas. I was not able to plug in the block heater.
I crossed my fingers for luck, activated the grid heater, then when it clicked off I restarted it for a second heat cycle. The starter strained and turned it over a little slower than normal but the old Cummins fired up on perhaps four cylinders. It rattled and shook for a minute or two until all six were firing evenly and smoothed out. That morning as I traveled west I saw probably a dozen 18 wheelers sitting on the sides of the highway waiting for roadside assist. Later that morning as I crossed the Rocky Mountains I saw - 28* on the overhead computer panel.
I have never used anything but ordinary petroleum base diesel lube oils in the prescribed 15-40 weight in 650k miles of use. I have never added anti-gel until I expected ambient overnight lows to get below 15* and then only used basic Power Service from Wal-Mart. I always carried a few quarts with me for that purpose. I have never experienced fuel gelling and never have had a Cummins fail to start.
If your batteries are not of excellent quality, not fully charged, or perhaps you have a loose or corroded connector somewhere in the loop you may not have adequate voltage to spin the starter and provide full current to the grid heater.
I know 32* seems cold in southern Louisiana but it is mild summer day for many who live farther north. Your Cummins shouldn't even notice it is cool at the freezing mark.
Seafoam is a solvent so if there was any trash in the system it has reached your filter. Personnally, after reading it's main ingrediant on their website, I wouldn't dump it into my fuel, or my oil for that matter. It has to get a lot colder than 30 degrees for gelling to affect the startup, so IMO you need to look elsewhere.