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Discussion Starter · #1 · (Edited)
I have purchased my first diesel on Monday, an 06 LBZ, 90k miles. Issue is that it has already failed to start twice now. Batteries were tested by Oreilly auto and they said they were good but im not sure I believe them. First failure was in the morning at 40 degrees, other was 70 degrees in the afternoon both being first start in the day. Both times it started sputtered then quit and failed to start. The truck runs smoother than any other I have seen and always starts up easy after its been run.

My two thoughts are

1) Gelling fuel pluging filter- But it did not get very cold, maybe 20*
2) Batteries not up to par- I put my fluke across a battery and watched the VDC as it cranked and it diped low every time (10-11 VDC). Also took amp draws from each battery cable when nothing is on and I get nothing, 1 micro amp does not even register on my meter, so I dont think there is a draw on the battery when its not running

Both times I did not have someone to jump me so I pluged in the heater for an hour and then it started hard

The thing runs like no other once its started, no smoke and I really dont think its any thing major but I would like opinions on this forum.
 

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Discussion Starter · #3 · (Edited)
I dont really know what a fuel filter primer is. I know the dealer said they replaced the filter last week, maybe they messed something up? Do you think its loosing its prime or something along those lines?
 

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When they checked the batteries did they disconnect one from the truck? other wise tester is gonna read both.
 

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I have purchased my first diesel on Monday, an 06 LBZ, 90k miles. Issue is that it has already failed to start twice now. Batteries were tested by Oreilly auto and they said they were good but im not sure I believe them. First failure was in the morning at 40 degrees, other was 70 degrees in the afternoon both being first start in the day. Both times it started sputtered then quit and failed to start. The truck runs smoother than any other I have seen and always starts up easy after its been run.

My two thoughts are

1) Gelling fuel pluging filter- But it did not get very cold, maybe 20*
2) Batteries not up to par- I put my fluke across a battery and watched the VDC as it cranked and it diped low every time (10-11 VDC). Also took amp draws from each battery cable when nothing is on and I get nothing, 1 micro amp does not even register on my meter, so I dont think there is a draw on the battery when its not running

Both times I did not have someone to jump me so I pluged it in for an hour and then it started hard

The thing runs like no other once its started, no smoke and I really dont think its any thing major but I would like opinions on this forum.
Does it crank over slow/barely or does it crank over pretty fast/strong?
And, when you say that you plugged in for an hour -are you referring to a block heater or a battery charger?
 

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On my Lb7 I had a problem where it was loosing prime and it was the little plastic screw to bleed it. I would doubt it's glow plugs because they really don't even need to glow to start them. At least my starts really good when it's cold. Next time it does it pump the primer and see if it lost its prime. When i parked mine with the front end pointing up it always would lose prime. If i faced downhill it didnt do it as much. Also the batteries should obviously be at 12 volts. But that probably isn't the issue


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Discussion Starter · #7 · (Edited)
1) when we tested the batteries one was disconnected, previous owner thinks they are 2 years old and had no problem to speak of. Although he lived in Mississippi and I live in Nebraska- different temps I would assume. Reads 12.3 VDC when not cranking / 10-11 when cranking

2) Initially it cranks fairly fast and strong, then dies down with tries.

3) I did not have a battery charger with me, I pluged in the heater, whether or not it made the difference it was all I had to try at the time.

4) After a little bit of quick research on the fuel filter primer I checked mine and it feels very firm now but I have just gotten home, its still hot. Maybe that bleeds down? It is pointed up hill currently so ill have to check in the morning.

And thanks for the quick help, any other forum takes days to get an answer
 

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Ya normally mine would do it in the mornings. Is that how yours is? Or after it sits for a few hours? It won't bleed down that fast. I'd try to start it in the morning and if it doesn't check the primer. And if your getting 12 volts then I would doubt the batteries are an issue but it does sound like they are getting week. Have you load tested them?


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Other problems you can have besides a loose bleed screw is the filter head may be leaking. You can buy the kit and fix. You may want to check into that if you're losing prime also


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Your truck should fire within 5 seconds of turning the key, even at 20 degrees and no block heater. If you are having to crank it more than once for that time, there is something other than the batteries causing you trouble. Do you turn the key and give it a moment before you crank it over? Do you know about the glow plug warming light on your dash that lets you know when to crank?
Just checking.... --Mike
 

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Just checking in to see if it started this morning. Let us know what happened


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Discussion Starter · #13 ·
I do know about the glow plugs and I let the cycle till the light goes out, seems like 2-4 sec when its cold.

Well it started this morning, easily. I drove 150ish miles today and everything was flawless. I checked the bleeder screw and it was already tight last night. I also checked the primer this morning before starting it and it was very firm.

When you guys replace your fuel filters does it lose its prime the first few day or days after? Im sure priming issues fit my situation.
 

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^^^ No, that doesn't happen.
As Larson mentioned above, you may need to rebuild the filter head.
It's a cheap & easy place to start.
 
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