LB7: #1 injector shorted

2004LB7

2004LB7

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I swapped out three on my LB7. Ran great with good balance rates after.

Keep all of the small parts, etc below the solenoid in place and only swap the coil. After unscrewing the solenoid, carefully lift it straight up and all of the other parts should remain.

If you are not comfortable with it then replace the whole injector. But dont use the one from Pensacola
 
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Tylerrc34

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I will heed the warnings of Pensacola FI. Thank you.

2004LB7 I found your post in a thread about replacing an injector solenoid without removing the injector. You said...

"I have done this to two injectors so far. I had to make a special socket from a metal tube to fit the solenoid. I didn't have any issues with the return line or injector twisting much that caused any leaks."

Then bmc1025 said...

"You will have better luck soldering than messing with taking off the solenoid. There is a very small ball bearing that can come out of its seat and make your life a living Hell. I have good eyesight and this ball is so small you need a magnifying glass just to confirm if it is still in place."

I found a breakdown of the injector in this thread...

https://www.dieselbombers.com/lb7-performance/111843-duramax-lb7-injector-disassembly.html

and it looks like the tiny ball bearing that bmc1025 is talking about is further down into the injector and I wouldn't have to worry about it if I'm just replacing the solenoid.

How tight was the nut to remove the solenoid off the injector and do you have a picture of the tool you used to remove it?
 
2004LB7

2004LB7

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Tylerrc34 said:
I will heed the warnings of Pensacola FI. Thank you.

2004LB7 I found your post in a thread about replacing an injector solenoid without removing the injector. You said...

"I have done this to two injectors so far. I had to make a special socket from a metal tube to fit the solenoid. I didn't have any issues with the return line or injector twisting much that caused any leaks."

Then bmc1025 said...

"You will have better luck soldering than messing with taking off the solenoid. There is a very small ball bearing that can come out of its seat and make your life a living Hell. I have good eyesight and this ball is so small you need a magnifying glass just to confirm if it is still in place."

I found a breakdown of the injector in this thread...

https://www.dieselbombers.com/lb7-performance/111843-duramax-lb7-injector-disassembly.html

and it looks like the tiny ball bearing that bmc1025 is talking about is further down into the injector and I wouldn't have to worry about it if I'm just replacing the solenoid.

How tight was the nut to remove the solenoid off the injector and do you have a picture of the tool you used to remove it?
Click to expand...

I know very well of that little ball he is referring to. By the way, that thread of the injector disassembly is my thread and those are my photos.

Yes, if you drop the ball good luck finding it. But if you are careful as mentioned above, you should have no problems with it. And yes it is further down and not right under the coil.

The part about "soldering" was for fixing a broken stud on the coil as apposed to replacing it. There have been a few instances of tightening the nuts to much and breaking the studs. This was a way of dealing with that

As for the nut holding the coil, it didn't seem too tight but it was snug. I'll see if I can find the tool I made. I'm not sure it is still around as I sold my LB7 and got me an LMM
 
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Tylerrc34

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Oh man you are all over the web with injector info! :thumb:

I will totally take a whack at the solenoid before going for the whole injector replacement.
 
2004LB7

2004LB7

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Here is a picture of the tool I made. Nothing fancy. Just some one inch EMT and connector

The one on the left is the first one I made but it didn't grip too well. I made the one on the right when the 3rd went out on me. I heated it up witb a torch until red and tapped it over another (bad) injector to for the shape. To use it you tap it onto the injector solenoid nut and use a pair of channel locks to loosen it up. Not complicated at all
 

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Tylerrc34

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Brilliant. I would ask if I could buy it from you but it would be faster if I made my own. I just need to get a hold of a bad injector.
 
DAVe3283

DAVe3283

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Tylerrc34 said:
Brilliant. I would ask if I could buy it from you but it would be faster if I made my own. I just need to get a hold of a bad injector.
Click to expand...
There's also the one currently in your truck with the bad solenoid. That's what I'd do. Stuff rags around it in case metal scale flakes off as you hammer the "tool" on.

Sent from my Cat S60 using Tapatalk
 
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Tylerrc34

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So major breakthrough this morning...

but first I adjusted my valve lash which I quite enjoyed. I wasn't going to remove my driver side valve cover for nothing. I'm looking forward to hearing how quiet she runs after that.

I was worried about having to remove my lower valve cover which I know could be done with lots of patience but those bolts were so tight and one was even changed to a philips screw head in the past so there was no way I was getting that one off without a grinder or welder.

With the possibility of being able to remove the solenoid with the lower valve cover still on, I first tried gripping with a vice grip, no luck. I knew I was going to have to make a tool so I headed to Home Depot on my OneWheel and rode home with a 10' long piece of conduit and forged away.

Sure enough, the tool worked!!!:woott: Thank you 2004LB7!

So I'm going to button up the driver side, reinstall my drive belt, clean some parts and get ready to install the solenoid when it gets here Friday.
 
2004LB7

2004LB7

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Tylerrc34 said:
so I headed to Home Depot on my OneWheel and rode home with a 10' long piece of conduit and forged away.
Click to expand...

This is the image I get reading that :roflmao:
0974%20%20Tightrope%20Unicyclejpg.ashx
 
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Tylerrc34

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I wish I could send a picture of the actual event. You're not far off, just modernize the image.
 
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Tylerrc34

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picture.php


Perfect gadget for when your Silverado breaks down. Fortunately I have a Home Depot and Advance Auto right down the road.

That's not me.
 
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Tylerrc34

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Update...

I received the solenoid last night, installed it with seemingly no complications and reassembled the engine. I bought a new fuel hose because it was old and worn (FICM to fuel filter) and new banjo bolt washers for the FICM (they were pretty beat up) and started priming the fuel.

I took the priming bolt out (I have a metal one) and primed until fuel came out, tightened it and the truck wouldn't start on the first try. I did this about 10 times, each time the truck sounded like it was almost there and light white smoke would come out of the tailpipe.

Finally the truck started but ran very rough and THICK white smoke came pouring out of the exhaust. I have a crankshaft position sensor code coming up, P0335.

Every time I prime I see the milky air/fuel mixture coming out, that's with the primer bolt lightly threaded in but I have been priming for AGES! I mean I primed so much I had to check my fuel gauge I thought I might run low and the milky mixture is STILL coming out.

What's going on?
 
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Tylerrc34

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I should add that if I prime rapidly with the primer bolt removed, I do see larger bubbles. If I prime very slowly I don't see any bubbles.
 
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