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My Project

80K views 244 replies 29 participants last post by  sables91  
#1 · (Edited)
I decided to start a thread on my work which began the day after I bought the truck from the dealer. This is my 2nd diesel - I had an '07 Cummins 5.9 and modded it heavily, went through 3 trannies, and ended up trading it on a new GMC Sierra gas truck last year for my business.

Anyway, I got this white LML this past September and started with the little stuff - wheels and tires the first day, Banks CAI, Cognito UCA kit with Fox shocks among others.

I have PM'd Don and Ashley and one or two others and a couple of the vendors herewith questions and already I have had tremendous support and guidance, which is probably the underlying reason for these forums in the first place. Don encouraged me to post a thread on my process and I decided that if I could help any forum member in any way by doing so then I'd be happy to do it. So here goes.

The task I am attempting is something I have NEVER done before. I am very mechanically minded, but often bite off more than I can chew and get myself into all kinds of shyte along the way. The toughest thing I have ever done is replace a clutch plate on a 5 spd 1992 Toyota Celica GTS... alone... in my garage. And it ran pretty well for years afterward, so I can turn a ratchet if I need.

But this..? Definitely way beyond me. Especially with no instructions. So, I really need some help.
Please feel free to comment, chip in, donate, criticize, whatever... help, even. I still have lots of questions.

I am giving myself about 6 actual work days to do the work, and its not really "myself" its a diesel guy at a shop I really trust. His name is Jim, and he has worked on many LBZ's extensively, and the odd LMM a little, but never an LML. Did his apprenticeship as a diesel guy with a GM dealership (may not be a good thing :D ) The owner of the shop has a warmed up LBZ, & is a mate of mine, he did some of the work on my Cummins and maintains much of my business vehicles, and he is happy to have me work with Jim and let Jim get the experience of doing these mods using my truck as the test vehicle. Basically, its a big experiment being conducted by two idiot rookies who could destroy some really expensive gear in a minute. Fun!

So... Here's the game plan:
OUT COMES the exhaust, DPF, DEF tank, down pipe, up pipes, manifolds and about 80lbs of other unnecessary things I gather are not needed...
IN GOES new manifolds up pipes, down pipe, exhaust, Fuel Lift pump, and some other goodies.

In the first 2 days, Jim and I (me part time in between running a job site 8 miles down the road) got through the "OUT COMES..." part, drew blood a few times, and did not break anything we need to re-use. We did come up with questions which hopefully I have answered using Don's thread, but we shall see.

So here goes:

Wheel well liners out... Passenger side shows a clear path, but drivers side reveals a tough task ahead.

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#189 ·
So, today I changed out the passenger side charge IC pipe, among other things.

After disconnecting both batteries, the first thing I did was remove the Banks air filter box, intake plumbing, and sensor. After that I removed the entire CAI and at that stage I could see everything that I needed to get to today. Then I went down below and removed the wheel well liner and removed that, to get access to the bottom of the intercooler. Before I could get to the intercooler pipe though, I had to remove this air box base bracket, which also serves as a locator for the engine coolant reservoir.

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Then I released the IC pipe at the bottom and at the top where it connects to the "throttle body" thing. This is done by twisting the outer ring to the left about 1/2" and tugging on the tube, and it slips off. These twisting lock rings are on both ends of the bottom section of the IC pipe. Before removing this bottom half of the IC pipe, I disconnected the sensor plug and unscrewed the probe from it, then remove the pipe from the engine bay. Then I went to the battery area and I unbolted the fender brace to get easy access to the passenger side battery.

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#191 ·
The battery part of it is quite easy. Remove the red rubber protective cover and the big fuses are revealed. 13mm socket does it. Remove the nut on the middle one. But first make sure its the correct one by tracing that red cable all the way to the heater block on the throttle body.

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When you've done that remove the ring connector...

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Then trace the wiring loom back a ways - maybe 8 inches or so to where they are all bound together, and snip the sheathing with a pair of scissors. Then you can remove the cable for the heater block, and tape the remaining wires back together and replace the nut on the battery and the red rubber cover.

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#192 ·
Now for the fun stuff - pulling all that expensive GM metal out of the truck!
First thing to do is remove all the electrical sensors and plugs from this throttle body.
With the lower IC pipe out of the way you will see a metal bracket with 2 bolts which you need to remove. They are below and forward of the heater block of the throttle body. I kept all my bolts to one side just incase I needed them for something (like if this process didn't work and I had to put it all back together again).

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Now go to the dip stick support bracket and remove these bolts shown below.

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Then I went to the back end of the charge pipe where it turns down and meets the Y-bridge, and removed the 2 bolts that secure it to the motor. I also removed the hose clamps (1 fore and 1 aft) and the wire loom fastener that hangs under the pipe.

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#193 ·
And now I had to reach for my sunglasses.

I put the hose on the bottom flange of the intercooler first and tightened that up, and then inserted the bottom section of the IC pipe from above and pushed it into the silicone hose. It went in really easy without any silicone or lubricant.
I used fine threaded 3.5" stainless steel clamps from my local Goodyear hydraulics supply store and everything seemed to go fine.

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The top section was even easier. I bolted the back end down tightly onto the Y-bridge after getting the hose coupled without tightening both clamps.

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Then I tightened the clamps and checked for clearances or possibilities of rubbing etc. Perfect. I then screwed the sensor back into the bottom section and plugged the other end of it back into its receptacle.

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#194 ·
Then I started putting everything back together in reverse order. The hex cap screw that calvin made for the MAF(?) sensor was too long and I had to cut about 1/4" off it. Otherwise everything seems OK.

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The only thing I didn't have was a nut for the dip stick support bracket which I found at Advance Auto. They couldn't find the right thread pitch, so I ended up getting a completely new bolt, nut and washer.

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All in all about 4 hours including a couple of other maintenance items. I washed my Banks air filter, tied up a few unused pre-delete electrical plugs that have been flapping in the breeze for the past 3 months, and removed my DEF tank brackets.

The engine bay looks even less cluttered now, although a little "flash".

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#196 ·
great write up! I'll be using this later today when I install mine :thumb
 
#198 ·
In the interests of temperature changes, here's what I have found so far:

Before today I could get up to 1305* on WOT 0 - 80mph hard runs.
This morning on 3 attempts highest I could see was 1209*
Maybe it was the coolness of the ambient temp outside or the fact that the previous time was on a tank without OptiLube... I dunno. But there is a difference.

Throttle response is a little more sharpish. Sounds a little like the old Yamaha FJ1200 when they first came out in the late 80s early 90's - "VOOOOOP!" and then the whistle as it comes back down. Nice.

I got my top pipe with only one port, and really I don't have anything to put in it, so I cut off an old thermocouple and screwed that in there to plug it up seeing that it is a tapered port.
 
#201 ·
For more clarity...

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Refer to the photo below...

1. The two Rubber hose lines indicated in yellow remain intact connected to the metal relief valve/device (indicated by the blue arrow) with the black plastic quick-connect. Or they can be connected to each other with a 3/16" 90* barbed fitting you can by from Grainger with clamps on both hoses.

2. The two ends of the 9th injector fuel line I snipped off and discarded (shown in red)

Report this image
Hey guys, I am trying to clean up this area. Are the lines marked in red common with the lines marked in yellow (post 110)? I see notes that you crimped the lines marked in red but will they have pressure through the cylinder? All I have is a brass 1/4" straight barbed connector and I am debating leaving the cylinder but I am not positive I can crimp the lines (shown in red) well enough to hold pressure.
 
#202 ·
Hey guys, I am trying to clean up this area. Are the lines marked in red common with the lines marked in yellow (post 110)? I see notes that you crimped the lines marked in red but will they have pressure through the cylinder? All I have is a brass 1/4" straight barbed connector and I am debating leaving the cylinder but I am not positive I can crimp the lines (shown in red) well enough to hold pressure.
The red/yellow lines do NOT appear to be common. I am going to pick up a barbed 90 and install when I do intercooler pipes. Sorry to jump in on your thread.
 
#203 ·
Quote:
Hey guys, I am trying to clean up this area. Are the lines marked in red common with the lines marked in yellow (post 110)? I see notes that you crimped the lines marked in red but will they have pressure through the cylinder? All I have is a brass 1/4" straight barbed connector and I am debating leaving the cylinder but I am not positive I can crimp the lines (shown in red) well enough to hold pressure.
The red/yellow lines do NOT appear to be common. I am going to pick up a barbed 90 and install when I do intercooler pipes. Sorry to jump in on your thread.
The Red and yellow lines are definitely not common. When I recently had my Suspension lift done I did some remedial work to that part of the "project". I got a 1/8" 90 degree elbow from a hydraulic store (Goodyear) nearby, and a couple of clamps and cut the hose lines marked in yellow, removed that whole device (fuel pressure return thingamabob) with the aluminum cylinder and its own bracket holding it in place. All gone now. I'll go take a pic...
 
#206 ·
Next question, if you will allow. What are you doing with all the leftover plug connections? Has anyone started cutting them out yet? I have them taped and tied but would love to get rid of them.
 
#208 ·
No, I was talking about all the unused wire plugs created from all the deletes. From following your thread it looks like you have them taped and tied like I do. I am thinking about cutting them back to the loom or further if possible.