06 Cummins cranking but no start

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Justin_case

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I have an 06 dodge 3500 that’s completely stock that turns over great but won’t start
-batteries are fully charged
-the engine will not do anything at all as far as trying to start, just cranks over
- for the last couple months I’ve noticed that after sitting for a few days I would have to crank longer than usual to start but it always started and ran fine. I’m pretty sure it’s not getting fuel but where should I start and what should I do??
Thanks (Also has no dash lights on )
 
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nlambert182

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Sounds like it's lost its prime. Try cracking the fuel lines open and cranking until you stop seeing air bubbles.
 

Smokeybear01

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Check your fuel pressure at the filter and make sure you have some. If you do you can eliminate the lift pump. Then look into your fuel pressure relief valve, that was my problem. Good luck, Smokey
 

Fast69Mopar

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Sounds like it's lost its prime. Try cracking the fuel lines open and cranking until you stop seeing air bubbles.
This is not one of the engines that you can bleed the fuel system by breaking the lines loose and cranking the motor over. While cranking the fuel pressure on tht fuel rail is very high. This motor requires at least 1700pei of rail pressure to even think about starting. On a healthy field system you will see 4500psi-75o9 pei right before it starts.

So, to reiterate, please DO NOT break the fuel lines loose and start cranking because you or someone else may get hurt.

Follow the proper service procedures for this particular engine and save your fingers and hands from bring cut off from fuel pressure.
 
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Justin_case

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Check your fuel pressure at the filter and make sure you have some. If you do you can eliminate the lift pump. Then look into your fuel pressure relief valve, that was my problem. Good luck, Smokey
To add to my post there are no dash lights on….. anyway I drained my filter housing then turned the key on and it filled back up with fuel and when I opened the drain with the key on fuel shot out pretty good so I’m assuming that’s fine. I found the fuel pressure relief valve, how would I check to see if it’s working correctly?
Thank you
 

Fast69Mopar

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To add to my post there are no dash lights on….. anyway I drained my filter housing then turned the key on and it filled back up with fuel and when I opened the drain with the key on fuel shot out pretty good so I’m assuming that’s fine. I found the fuel pressure relief valve, how would I check to see if it’s working correctly?
Thank you
The test the pressure relief valve removed the banjo from the top see if there is fuel inside. If there is fuel the valve is leaking.
 
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Justin_case

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The test the pressure relief valve removed the banjo from the top see if there is fuel inside. If there is fuel the valve is leaking.

The test the pressure relief valve removed the banjo from the top see if there is fuel inside. If there is fuel the valve is leaking.
I took that banjo fitting loose and before I even had the bolt out fuel was leaking out and dripping off the fprv so it was definitely full of fuel so I guess I’m off to town to get a valve and hopefully that does it. Thanks a lot!
 

nlambert182

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This is not one of the engines that you can bleed the fuel system by breaking the lines loose and cranking the motor over. While cranking the fuel pressure on tht fuel rail is very high. This motor requires at least 1700pei of rail pressure to even think about starting. On a healthy field system you will see 4500psi-75o9 pei right before it starts.

So, to reiterate, please DO NOT break the fuel lines loose and start cranking because you or someone else may get hurt.

Follow the proper service procedures for this particular engine and save your fingers and hands from bring cut off from fuel pressure.
Yep my bad... I forgot that 06 was a common rail.

OP - disregard what I said previously. What you can try instead, is to cycle the key to on and listen for the lift pump. If you don't hear it, check your fuses first. If they're all good, chances are the pump has been getting weak and is now dead.

If you DO hear it, turn they key off, place a bucket under the fuel filter drain, open the drain valve, and then start cranking the truck. You should be getting roughly a pint of fuel every 6 seconds of cranking. If you're getting less than that, it may have killed the injection pump.
 

Smokeybear01

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I took that banjo fitting loose and before I even had the bolt out fuel was leaking out and dripping off the fprv so it was definitely full of fuel so I guess I’m off to town to get a valve and hopefully that does it. Thanks a lot!
The valve torques in at 74 foot pounds and the banjo bolt at 18 foot pounds. DO NOT use any type of anti-seize or sealant on any of the threads and whatever you do, don't let any dirt get into the port where the valve screws in-IT WILL REACH THE INJECTORS AND CAUSE MAJOR PROBLEM. Good luck,
I should also add, this system will generate over 26,000 PSI in the rail. Let it sit overnight if possible before you remove the relief valve just in case it didn't mal-function and is holding pressure behind it.
 
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Justin_case

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The valve torques in at 74 foot pounds and the banjo bolt at 18 foot pounds. DO NOT use any type of anti-seize or sealant on any of the threads and whatever you do, don't let any dirt get into the port where the valve screws in-IT WILL REACH THE INJECTORS AND CAUSE MAJOR PROBLEM. Good luck,
I should also add, this system will generate over 26,000 PSI in the rail. Let it sit overnight if possible before you remove the relief valve just in case it didn't mal-function and is holding pressure behind it.
Ok great thank you for the torque specs and advice. The only place I could find a FPRV in the town closest to me was the ram dealership. They wanted 1384$ for it wtf ………. I ordered one on diesel power products for 140$ delivered and it’s a Bosch So the truck will sit till I get it in a couple days. I appreciate the help! Thank you very much. I hope this does the fix! Thanks again !
 

Fast69Mopar

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I took that banjo fitting loose and before I even had the bolt out fuel was leaking out and dripping off the fprv so it was definitely full of fuel so I guess I’m off to town to get a valve and hopefully that does it. Thanks a lot!
Sorry I didn't see this earlier. I have been diagnosing the relief valves this ways since their inception into Ram Trucks. There is a specific procedure in the service manual to test it but removing the banjo and inspecting for fuel has never failed me.
 

NonCents

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I have an 07 2500 with a 5.9L (500K miles) that started doing the same thing. Spray some starter fluid in the air filter... if it starts and runs it is really a simple answer just not a simple solution. If it starts then one of the injectors is leaking down. So you have to either try and figure out which one, or in my case if you are going to be that far into the engine, replace them all. I did that about a month ago and it fires up normal ever since. I would say since you say it runs fine if started, this is what is going on. It is not a hard job, just time consuming. #6 is kinda hard just because it is behind the lift hook. I replaced the injectors, tubes, lines, and valve cover gasket with all injector electrical when I did mine.
 

Aircommuter

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If you are trying to get fuel flowing after changing the filter you need to turn the key on and hear the pump running, then it will stop as a safety measure because the engine wasn’t started. You may need to do this several times. That part of the system may be tested with a pressure gauge as it is low pressure to supply the common rail pump. It’s the old first things first. That year model has a tank located pump. Common rail was started in 2003.
 

Smokeybear01

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I have an 07 2500 with a 5.9L (500K miles) that started doing the same thing. Spray some starter fluid in the air filter... if it starts and runs it is really a simple answer just not a simple solution. If it starts then one of the injectors is leaking down. So you have to either try and figure out which one, or in my case if you are going to be that far into the engine, replace them all. I did that about a month ago and it fires up normal ever since. I would say since you say it runs fine if started, this is what is going on. It is not a hard job, just time consuming. #6 is kinda hard just because it is behind the lift hook. I replaced the injectors, tubes, lines, and valve cover gasket with all injector electrical when I did mine.
You are absolutely correct, but hopefully it's just the pressure relief valve this time and when there is fuel in the banjo bolt, that's usually it. Much simpler than doing injectors. Thanks for the input, Smokey
 

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