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Discussion Starter #1
I just replaced the injectors in my 2006 5.9 Cummins. I was starting to have misfires and it was smoking even at idle, and at one point in the last two years, I had to retorque my crossover tubes, they were all loose. So I figured the injectors and tubes were just worn out.
The install went alright, but I had an issue with the #1 cylinder, and I thought maybe I just didn't follow the procedure just right, so i re-did the whole install on that. It turned out to be the fuel line. I got a new one, and that seemed to fix the issue.
600 miles later, Its got a vibration at idle, if you grab the intake horn, it feels like someone it thumping your hand. A Cylinder Contribution test shows that #1 is at 88-95% (depends on temp) and the rest are 100%. and an Injector kill test doesn't result in any change of RPMs.
To see if its the injector, I swapped #1 and #4, and now both of those are 95%(#1) and 92% (#4). I didn't run the kill test due to time, but I imagine it will be the same as before. The only thing I can think of, is I didn't install a new copper crush washer when pulling the newly installed injectors. Could that cause me to have a compression leak? Anyone got any ideas? TIA.
 

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What brand injectors thousands of issues with knockoff and or remans .
Only NEW Bosch or BBI with new connector tubes and washers, hopefully have not damaged engine

FWIW , should always use new washers and connector tubes that is what seals injector to cylinder and fuel connection to injector. 40+ft/lbs for dirty threads on head
 

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Clayton @ DDP Motorsports
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Like stated new washers/connector tubes are always recommended as well as cleaning out lines, fuel filter bowl and changing filters. i know most of the time customers are short on time but when dealing with the fuel system cleanliness is extremely critical when it comes to something as important as injectors.

What brand injectors did you go with my friend?

Clayton
 

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Send those injectors back to whoever you got them from for warranty replacement or just demand your money back if they're not Bosch factory or BBI's.
Run compression tests.
Always spray out the connector tube holes in head and injector mounting holes with brake cleaner. Final blow out with compressed air. Krap that breaks loose doesn't hurt anything in cylinder, will cause bad JuJu if left in the threads or holes

If you would have left a copper seal out, you would immediately know it. 2000 psi++ combustion gases would be blowing out of the engine crankcase every hole it could find. Look like a steam locomotive and sound like it
 

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Discussion Starter #5
The injectors are New Bosch. I got new tubes as well.

I know i didn't leave the copper washer out, but I've installed, pulled and re-installed two of the injectors, I guess my question is, do I need a new crush washer every time you pull an injector?

I made sure I was extremely clean when doing the install, I did not spray brake clean through the fuel return gallery, but I did blow it all out and make sure everything was damn near spotless before putting new parts in. Crossover tubes are new 6.7 style, SS. torqued to 44ft-lbs.
 

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Clayton @ DDP Motorsports
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The injectors are New Bosch. I got new tubes as well.

I know i didn't leave the copper washer out, but I've installed, pulled and re-installed two of the injectors, I guess my question is, do I need a new crush washer every time you pull an injector?

I made sure I was extremely clean when doing the install, I did not spray brake clean through the fuel return gallery, but I did blow it all out and make sure everything was damn near spotless before putting new parts in. Crossover tubes are new 6.7 style, SS. torqued to 44ft-lbs.
some people do not replace those crush washer and have great luck but many others have terrible luck. the crush washer is designed to be used once. ( crushed once if you will )
 

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Discussion Starter #7
Alright, So I pulled #1 and #4 and re-installed them again, this time with new crush washers. initial startup, nothing changed. I took it out on a test drive, and got it to operating temp, and it blew a bunch of crap out the tail pipe, and after that, it idled and drove correctly. However, sitting in the driveway, I reved it up to about 2500, and between 1700-1900 RPMs, it had a harmonic vibration. It shouldn't be the clutch, it a dual disk valair right after i bought it, and everything on the font of end of the engine is new(er), except the fan and power steering pump.

after shutting it down, I heard a few loud pings? almost like a spring is shifting back into position? Is that normal? Its never done that before, and I've had this truck for 40k miles. and I had a 05 for 80k miles, and I've never heard a ping while the engine is cooling down...
 

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I skimmed and didn't see it. You did do the valve lash right? And again after moving injectors around?
 

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Discussion Starter #9
I skimmed and didn't see it. You did do the valve lash right? And again after moving injectors around?
I lashed the valves to .010" for the intake and .025" for exhaust for everything while the engine was cold. Do i need to get the temp to 140+ and re-lash them?
 
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