01' hard start/knock/tons of white smoke after injector install

CATmech945 said:
Did he change the injector cups? Or at least clean the old ones up good before installing the new injectors? Sounds like some sort of issue with the way the o-rings are sealing. I've had them run rough after a fresh install but never as bad as you're describing unless something was installed wrong. O-rings flip flopped, etc.
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Thats exactly what i said but no one else has mentioned the cups... i thought it was recommended to change the cups in a powerstroke every time you replace injectors....arent they bad about cracking?

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They crack very easily if the injrctor hold down bolt aren't tight enough! Out of all the 7.3L injectors I've replaced I only had cup issues on one set and I fell it was caused by a loose hold down. Now that these trucks are coming in with well over 100K miles we're replacing cups more often.

Oil/fuel on the pistons will only cause problems on the initial start. We always leave the GPs out and crank the motor over by hand before we start them then we change the motor oil as well. If the engine is locking after it's ran awhile it can only be liquid entering the combustion chamber. If it's coolant there will be lots of pressure in the cooling system after you run it a while. If combustion gasses enter the fuel system all sorts of weird chit can happen but I've never seen one hydro lock. However it would be possible if it's leaking fuel badly enough that fuel enters the cylinders as soon as the key is cycled on...I would suspect this if there is a bad misfire that will not clear up and the cooling system appears fine. Cracked cups can also cause fuel/coolant cross contamination.
 
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Mudn_1 said:
Thats exactly what i said but no one else has mentioned the cups... i thought it was recommended to change the cups in a powerstroke every time you replace injectors....arent they bad about cracking?

sent from my damn phone
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No you dont have to replace the cups everytime you replace injectors. You should pressurize the cooling system thou while they are out and check the cup for leaks.. cleaning the cup should be a no brainer, spaying them with good parts cleaner is usually all it takes.Sometimes thou if the engine has been run hot the O-rings will stick and you can use an inj cup brush to clean them up nicely.
 
Would it be safe to assume that your buddy doesn't know much about these engines?? I'm not by any means taking a shot at your friend but I've seen people literally yank the old injectors and stick the new one's in without looking in the hole simply because they don't know any better. I would pull the injectors back out, check the order of the o-rings, pressure test the cooling system for leaks and clean the cups good. Check the oil and coolant too and make sure it doesn't have fuel in it. It's really easy for someone to screw the process up especially if this is their first whack at it. If the problem persists then go to bean's.
 
Just pulled injectors out of a 169K mile '00 F550 this morning with rough run issues, white smoke and low power. All the injector tips have major carbon buildup and one injector cup is cracked. ;)
 
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CATmech945 said:
Would it be safe to assume that your buddy doesn't know much about these engines?? I'm not by any means taking a shot at your friend but I've seen people literally yank the old injectors and stick the new one's in without looking in the hole simply because they don't know any better. I would pull the injectors back out, check the order of the o-rings, pressure test the cooling system for leaks and clean the cups good. Check the oil and coolant too and make sure it doesn't have fuel in it. It's really easy for someone to screw the process up especially if this is their first whack at it. If the problem persists then go to bean's.
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yes.....

I would have done things differently, although I am powerstroke stupid too.... but I have done enough injector installs on cummins to know precautions to be taken.....

and NO word on the truck, i havent spoken with him in a while..
 
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