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Discussion Starter · #1 ·
Well i feel like i have asked too many ?s on this subject but here goes again. First off, @ 2 weeks ago i was hearing an inj. knock, the dealer said it wasnt an inj but maybe a broke wristpin in #1 cyl. they pulled head and #1 cyl was scored a little,so they said they were gonna put in a new shortblock. Well 2 weeks later the new shortblock is in and running but it is still at the dealer. They say it has a miss in #2 and #6. They moved the injectors around to see if the missing followed the injectors, they did not, so they dont think its the problem. They have told me that too much fuel is being returned to the tank. They are gonna put 6 new injectors in on the 22nd, this is when the mech. gets back from his vacation. (sucks for me huh). I dont think the injectors are the problem,but i will take the new ones anyway. Now why does the new motor have these misses when the old motor that had a scored cyl. ran fine,didnt smoke,still had good power, only had a lil knockin not have these misses. I know im about to go nuts trying to figure this out. DOES ANYBODY HAVE ANY SUGGESTIONS !!
 

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Sounds to me like the tech screwed up when reinstalling the injectors.
 

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Discussion Starter · #3 ·
how so, I dont know much @ workin on the inside of em. He seems to know quite a bit, he was doing tons of tests the other day but nothing worked.I dont want to get too impatient w/em because of my mods and the fact that they are doing all this under warranty.
 

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He might have nicked an injector o-ring when installing them. They'll figure it out.
 

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Discussion Starter · #5 ·
Thanks Tech, i will find out in a week iguess, i will mention the o-rings to him.I did ask him if he torqued all the inj tubes right and he said yes, he even said the trq. specs he used. I dont recall wat they were but i assumed he looked them up. Thanks again.
 

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Thanks Tech, i will find out in a week iguess, i will mention the o-rings to him.I did ask him if he torqued all the inj tubes right and he said yes, he even said the trq. specs he used. I dont recall wat they were but i assumed he looked them up. Thanks again.
I'm not sure I'm just throwing stuff out there. Sounds to me like he knows what hes doing. Hey no prob.
 

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If any dirt or other debris get in the injectors when they are removed or upon removal it will damage them. Also the high pressure connector tubes need to be replaced when new injectors are installed. Make sure they do that or that will also cause excessive fuel return to the tank. Torque on the injectors are 133 in lbs on the connector tube nut, 89 in lbs on the injector hold down, and then 34 ft lbs on the connector tube nut. Hope this helps,
 

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Discussion Starter · #8 ·
They didnt replace the inj. yet they just swapped them around. I didnt know that the tubes needed to be new with new injectors.
 

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Discussion Starter · #10 ·
Got my truck back, new shortblock-6 new injectors, Under warranty. Truck seems to run fine now but ive only put @ 100 miles on it so far. Im gonna test it out and use it tomorrow to haul a load of pools about 250 miles. This is a bit heavier than i would like to put on it so quick. I have to get back to work tho. I will take it easy,55 mph and watching my guages more than the road probably. Anybody have any tips on what not to do while hauling so quick after a new shortblock.
 

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no tips but congrats on the new motor man:thumbsup
 

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Discussion Starter · #12 ·
Thanks, i got pretty lucky with the warranty. The dealer was waay cool about my mods. I know i should put a few more miles on it before towing heavy, but i will take it easy and hope everything works out.
 

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Keep your temps low and be easy. It won't be that bad for it they like to work. I would run it easy for 500-750 miles change the oil and then you should be able to start rollin' with it.
 

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Run it hard, don't baby the thing. Do you think the big truck drivers whether a company driver or independent go easy on a new truck. NO WAY, they get the truck find a load and time is money. The reason our owners manual tells us not to tow for 500 miles is the rest of the drive line not the engine.

BTW, if you got 6 new injectors and they are the latest version, you have a better injector now, so you win again. :)
 

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Discussion Starter · #15 ·
Whats this about the latest version of injectors? Whats the difference in them?
 

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The latest version have a coating on some internal surfaces of the injector that were eroding due to high fuel pressure and hard small particles in the fuel smaller than the filter can remove. This coating improves the wear resistance in the injector.
 

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Discussion Starter · #17 ·
do all of the new ones have a coating or do they still use some non coated ones? I have put about 800 miles on the truck so far and by tomorrow night it will have 1300, so im gonna change the oil this weekend. Then next week im gonna get on it a bit more. Should be fine the wek after to work it like usual.
 
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