Injector hot torquing.
#1
Injector hot torquing.
Hey guys. There has been debate, small and civil, but still debate about whether or not hot torquing our injectors is necessary. Well a good while back I did some work on my truck. Radiator water pump rebuilt my oil cooler and injector orings. I wrapped it all up cold, torqued my injectors cold and called it good. 1000 or so miles later my 7.3 was back to being loud with knocking and clattering and ticking so I decided I would go back in a re torque my injectors, but do them hot. Doing so I was able to get a complete round on the hold down bolts. And of course it's much quieter, no knocking or ticking, just the normal 7.3 sounds. I just wanted to throw this out there. It is a fact that injectors should be torqued with the engine hot rather than cold. And yes I'm sure they were torqued properly the first time.. only on a cold engine. Thanks for reading.
#2
^^ yes it's true I also learned that the hard way when I first starting messing with the 7.3 engines at work along time ago, I also notice that if you clean the bolt and threads with brake cleaner and blow dry them the torque on the bolts almost always stay with in spec when hot torqued just an FYI.
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Tee shirts! Get your "I have a loose screw" tee shirts here! No need to push, I have plenty of 'em.
I figured as long as there's a crowd, I'd sell off some of my excess inventory. I had a hard, miserable lesson sorting this one out - I couldn't find anybody at the time who knew this issue before me.
I figured as long as there's a crowd, I'd sell off some of my excess inventory. I had a hard, miserable lesson sorting this one out - I couldn't find anybody at the time who knew this issue before me.
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I then hot torqued the lowers to something north of factory spec which as we all know is 120 in/lbs. I don't want to start the old torque spec war of words here again; however, I watched/assisted a very experienced diesel tech install eight injectors. He allowed me to check the torque values post HIS install. I was a little surprised by the value that I found.
His thought is that the FORD/International torque spec is not high enough to properly compress/seat/seal the copper washer between the injector and cup and that this is what leads to loose/loud injectors.
I saw this engine crank and run immediately after the injector install and it was considerably quieter than most 7.3's at that point. I then saw it again after about 5k miles and it was still a very quiet engine. I now use that spec.
When I was at BTS in Feb'17, Brian stated the same exact thing totally unprompted by me while we were watching one of his techs do an injector install.
An added bonus is that the truck in my sig is quieter than it has ever been.
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I used 243 on the upper hold down bolts after thoroughly cleaning the bolts and holes when I changed injectors in Dec'16 because that is where my loose hold down bolt problem was.
I then hot torqued the lowers to something north of factory spec which as we all know is 120 in/lbs. I don't want to start the old torque spec war of words here again; however, I watched/assisted a very experienced diesel tech install eight injectors. He allowed me to check the torque values post HIS install. I was a little surprised by the value that I found.
His thought is that the FORD/International torque spec is not high enough to properly compress/seal the copper washer between the injector and cup and that this is what leads to loose/loud injectors.
I saw this engine crank and run immediately after the injector install and it was considerably quieter than most 7.3's at that point. I then saw it again after about 5k miles and it was still a very quiet engine. I now use that spec.
When I was at BTS in Feb'17, Brian stated the same exact thing totally unprompted by me while we were watching one of his techs do an injector install.
An added bonus is that the truck in my sig is quieter than it has ever been.
I then hot torqued the lowers to something north of factory spec which as we all know is 120 in/lbs. I don't want to start the old torque spec war of words here again; however, I watched/assisted a very experienced diesel tech install eight injectors. He allowed me to check the torque values post HIS install. I was a little surprised by the value that I found.
His thought is that the FORD/International torque spec is not high enough to properly compress/seal the copper washer between the injector and cup and that this is what leads to loose/loud injectors.
I saw this engine crank and run immediately after the injector install and it was considerably quieter than most 7.3's at that point. I then saw it again after about 5k miles and it was still a very quiet engine. I now use that spec.
When I was at BTS in Feb'17, Brian stated the same exact thing totally unprompted by me while we were watching one of his techs do an injector install.
An added bonus is that the truck in my sig is quieter than it has ever been.
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Originally Posted by jstihl
im about to do my orings and was interested in this torque spec. Would like to do this, but is there any negative aspects? Any nightmare stories of bolts breaking or anything?
#15
Things mentioned here make me wonder...is it a 'hot' torque that is required or is it a 'retorque', which is needed after running? If it's this big of a problem why wasn't it an issue when these things were fresh off the line?
And one other thing...is it supposed to be a dry torque? A dry torque won't be as snug as a wet torque. The thought of oil there would lead us to believe that it might be inclined to loosen itself up but it also changes the pressure that is applied by the bolt head.
And one other thing...is it supposed to be a dry torque? A dry torque won't be as snug as a wet torque. The thought of oil there would lead us to believe that it might be inclined to loosen itself up but it also changes the pressure that is applied by the bolt head.