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Discussion Starter #1
I thought it was a turbo coolant feed line or is it a return line? Or am I completely wrong? Either way it's leaking and I need to know what size and type of hose it is like high heat or high pressure.
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Fill out yer sig so we know what you've got. Hard to see with a big red marker thru it, BUT....the turbo coolant return line hooks into what I call a one way valve (others call it a T-stat) that screws into a port on the pipe that the top rad hose is hooked to. But the normal route for that goes down under the turbo neck/hot side pipe and not over it all.

With a screw clamp on it, it's already been replaced (OE has those spring clamps). What's leaking? The hose, or what it's hooked to on either end?
 

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Discussion Starter #3
The hose is leaking where it attaches to the turbo not the other end with that weird fitting and its in the red circle not through it I drive a 2001 chevy 2500hd
 

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A piece of 3/8" Silicone heater hose will hold up to the heat generated by that turbo
 

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Discussion Starter #6
Just got my truck back. they said headgaskets are a definite, quoted me at $5500 does that sound right? And he said the heads had to be machined even though he hasn't opened up the engine yet. I heard you don't have to unless its warped or has cracks.
 

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Do you have to order that type of hose or would an autoparts store have it
most parts houses dont carry it. online is where I foundit.

as for the Head Gaskets

In the morning before you start the truck. Squeeze the upper radiator hose. See if it is soft or hard like a tennis ball.

Hard is a nearly sure sign the head gaskets are leaking and need to be done.

Also pull you your dipstick and see if the oil is still black or milky. The milky color would be a sign of water in the oil.

You can also look for bubbles coming up into your surge tank when the truck is running and up to operating temperature

And last but not least a compression test will tell you if one cylinder or another is low, usually means head gaskets but can also mean valves or rings, or even a hole in your piston.
 

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Just got my truck back. they said headgaskets are a definite, quoted me at $5500 does that sound right? And he said the heads had to be machined even though he hasn't opened up the engine yet. I heard you don't have to unless its warped or has cracks.
Whoa, jumped from needing the coolant hose to the turbo to it needs head gaskets? Geez...
Something to keep in mind here, but an LB7 will present the same symptoms of a head gasket issue if an injector cup is lifted and not sealing properly. Has injector work been done on the truck recently? Has it been pushed harder than normal that could have increased cylinder pressures and cause a cup to lift.

The whole thing I try to get LB7 owners and people who work on them to understand is this- just because it has the same symptoms of a failed head gasket does NOT mean it needs head gaskets... It could be just an injector cup that is not sealed any more.
 

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Whew........I knew someone with more knowledge than I, about these engines, would pipe up sooner or later
 

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Discussion Starter #10
So is there any way to tell the difference? because $5500 is a shizload! How much would it be to fix injector cup?
 

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Discussion Starter #11
Sorry bout all the questions just love my truck and hate to see it go if I dont have to. I have serious trouble trusting mechanics especially when they know they could get lots of $$$$
 

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Sorry bout all the questions just love my truck and hate to see it go if I dont have to. I have serious trouble trusting mechanics especially when they know they could get lots of $$$$
LB7 injectors are located under yoru valve covers (Poor Design). When they leak, as in a raised cup, the leaking diesel goes into your oil.

Have you checked your oil level lately? See if the engine is "Making Oil", meaning the oil level rises as it becomes diluted with diesel (NOT GOOD). Others can chime in with even more info than I have.
 

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LB7 injectors are located under yoru valve covers (Poor Design). When they leak, as in a raised cup, the leaking diesel goes into your oil.

Have you checked your oil level lately? See if the engine is "Making Oil", meaning the oil level rises as it becomes diluted with diesel (NOT GOOD). Others can chime in with even more info than I have.
BUT a leaking/cracked injector body is not a lifted cup, and a lifted cup will not allow/cause fuel in the oil. They are two separate problems with two different corrections.

@Joelmichelle1 the only real way to know for sure is to do one of two things-
1- pull the injectors, pull the cups, reseal the cups and reinstall the injectors and see if that corrects the issue
2- pull the cylinder heads and go ahead and replace the head gaskets, and reseal the injector cups at that time as well
 

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BUT a leaking/cracked injector body is not a lifted cup, and a lifted cup will not allow/cause fuel in the oil. They are two separate problems with two different corrections.
Thanks for the education, my ignorance was on full display :confused:
 

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Thanks for the education, my ignorance was on full display :confused:
I'm not trying to belittle you or say you're ignorant or anything, just trying to help people know how it really works. There is so much misconception about the common LB7 issues, and I've been dealing with them for long enough that I just want to help people understand is all.
 

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Fear not, my friend, I did not take it that way at all. I was happy for the education.
 

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Just got my truck back. they said headgaskets are a definite, quoted me at $5500 does that sound right? And he said the heads had to be machined even though he hasn't opened up the engine yet. I heard you don't have to unless its warped or has cracks.
If you want to do a good head gasket job you most definitely want the heads machined. I wouldn't dream of doing a head gasket job on a diesel with blown gaskets without having the heads machined. I had a customer that had a head gasket replaced on a 6.7 Cummins and it started leaking again after less then a year...the shop that replaced it didn't have the head machined and it even had head studs. I had the head machined and no more issues.
 
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