LB7: Duramax not starting in cold

backtanner

Mr FNG to you
Jul 16, 2009
25
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Having a problem getting my 02 to start now that winter arrived. Thurs was high 30s and it started/ran fine. Fri was mid teens and it would just crank until batts started running low. Charged em up but get same results. No prob cranking, but doesn't sound like it even wants to go. I have had a P0107 (MAP snsr) that has been off/on but mostly on, that doesn't seem to have affected it for several months now. Fuel filter has less than 10k thru it. Glow plug light comes on for about 4-5 secs and then goes out.
 

MACKIN

Smell My Finger...
Aug 14, 2006
3,948
1
0
Connecticut
Have you tried plugging it in? Seems like the glow plug cycle is quick only 4-5 seconds at them temps unless you had it plugged in. From what I recall the truck needs to spin at 700 RPM so it might be time for batteries.

10K might be time for a filter change depending on quality of fuel you purchase. How do you get it started or does it finally start? Also you should make sure your not losing prime. Next time it gives you a problem pump up the primer and see if it helps.
 

ChevyTruckGuy78

Twins done Now for trans
Feb 7, 2010
694
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Ct.
hell its been 11 degrees here and i dont have my glow plugs hooked up or a grid heater and she fires up cranks a lil longer but fires up and a lil smokey but once warms up a lil goes right away not saying its the best thing but im just too lazy to get under the hood to reconnect the wires its too cold out and im runnin a single battery
 

MACKIN

Smell My Finger...
Aug 14, 2006
3,948
1
0
Connecticut
You aint bullshitting it's friggen freezing here and it sucks but I really shouldn't complain as it's been a good winter so far and we're day by day getting closer to spring!


Isn't 5-6 seconds a quick or to quick of a glow plug cycle in the teens? I think so as mine seems to cycle 5-6 seconds when it's 50 degrees out for a example.
 

ChevyTruckGuy78

Twins done Now for trans
Feb 7, 2010
694
0
0
Ct.
my light comes on for like 10 secs or so but i know its not hooked up somethign i forgot to do when i was messing with the twins and a few other things
 

backtanner

Mr FNG to you
Jul 16, 2009
25
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I'll check the fuel prime and the glow plug rails in the morning. Just seems odd that it would be perfect one day and dead in the water the next.:confused:
 

backtanner

Mr FNG to you
Jul 16, 2009
25
0
0
Checked the bleed port at the filter housing and no fuel. Pressed the prime button literally 500+ times with no fuel. plenty of fuel in tank. What is my next move?
 

MACKIN

Smell My Finger...
Aug 14, 2006
3,948
1
0
Connecticut
No lift pump? You might just have a bad primer and it isn't pumping up. We are assuming you are losing prime and thats why you have a no start. Your going to have to check for leaks . Probably right at the filter and or the housing,most likely anyway.
 

ChevyTruckGuy78

Twins done Now for trans
Feb 7, 2010
694
0
0
Ct.
X2 on the filter housing I yot a drip leak on the ttting on my lift pump but when I get time ill tighten it up in the mean time I'm stuck on the side of the road waiting for my buddy to bring me the lug nut socket ao I can tighten up my litany that mysteriously loosened up after a morning of plowing. Gonna kill who ever took it out of the truck and didn't put it back
 

MACKIN

Smell My Finger...
Aug 14, 2006
3,948
1
0
Connecticut
X2 on the filter housing I yot a drip leak on the ttting on my lift pump but when I get time ill tighten it up in the mean time I'm stuck on the side of the road waiting for my buddy to bring me the lug nut socket ao I can tighten up my litany that mysteriously loosened up after a morning of plowing. Gonna kill who ever took it out of the truck and didn't put it back

Tighten up your what? :rofl:
 

jet96

New member
Oct 20, 2010
84
0
0
Wideoming
I had that same deal before I put my lift pump on and it was one of the o- rings in the filter head, when it got down in the teens apparently they would stiffen up and allow fuel to drain back. My.02 worth
 

DonDeere

PROfessional Farmer
Jan 17, 2012
22
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upper midwest
Checked the bleed port at the filter housing and no fuel. Pressed the prime button literally 500+ times with no fuel. plenty of fuel in tank. What is my next move?

...you did tighten the bleed screw back up right??...

...I'm certain you did :thumb:

...if that is the case(dammit I said case :mad: ) then you may very well have an issue with the supply line/system coming from the tank "before" it gets to your filter base(sucking air instead of fuel)...

...or you primer has gone bad is another possiblity...unlikely but possible...

...did you take the filter off and refill it with diesel and then try it??...

...while diesels obviously need air to operate properly...when this air is in the fuel delievery system it is certain death for the starting of a diesel engine...

...I too have a 2002 Deere-A-Max with almost 200,000 miles and have yet to have any kind of starting issue even in much colder temps than you are experiencing...

...what have you found out??...let us know how it's going :thumb:
 

backtanner

Mr FNG to you
Jul 16, 2009
25
0
0
Yeah the screw was tight and had been since I changed out the filter about 4 months ago.

My plan is to reseat the filter and pull the line off the filter housing and check to see if I have suction at this point. If I don't have suction, I'm thinking of taking the filter head off and possibly rebuilding it. At least my problem seems to be from the filter mount back to the tank. Would have been a bad day if it were the other way.
 

MACKIN

Smell My Finger...
Aug 14, 2006
3,948
1
0
Connecticut
In most cases the problem of loosing prime will be right at the filter or filter housing. Could be a crack in the housing from vibration a O-Ring not sealing which can show up when it contracts do to the cold or even a stuck check ball allowing fuel to return to tank. But since your having a issue not being able to prime it I'd look more to a bad seal at the filter itself either top or at the bottom.

Put a lift pump on it ,best medicine plus it can prolong the CP3 as it wont work as hard. Not proven but suggested anyway keeping a constant flow to the CP3. Even if your 100% stock a lift pump has it's advantages.
 

backtanner

Mr FNG to you
Jul 16, 2009
25
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0
Took my filter/housing off and will check it out at work tonight....Had a bunch of dirty graphite looking stuff in the filter. What is there between the filter and the tank? I know from doing the injectors you can get fuel in the oil. But can you possibly get oil in the fuel???

Speaking of lift pumps, does anybody have a link to a write-up on installing one.
 
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backtanner

Mr FNG to you
Jul 16, 2009
25
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Rebuilt the primer and changed the filter and got her started right up. Damned if I know how it lost it's prime though.:D:D