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2004 G35, 2019 Nissan NV200
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Discussion Starter #1
This is my first "how to" thread so please bear with me!

So before attempting to replace the turbos on your 3.0 Q50, you must make sure you have the proper Tools... if you're attempting a job like this I will just assume you have the basics (sockets, ratchets, wrenches)
What you may not have though is:
  • Lift Table
  • Vehicle lift
This job requires lowering the subframe WITH the engine and trans assy. The vehicle body will be lifted up and the table will be holding the assembly.

Ok first, let's pop the hood, and do a quick visual inspection. It may be a good idea to take a few pictures, in case you get confused on the re-installion portion and forget how or where a harness or coolant line lays etc...

Mine looked like this
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And with the engine cover off
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I forgot to take a picture of this step, but one of the first things you need to do is drain the coolant. There are 2 separate cooling systems on this model. The engine cooling system. And the intercooler cooling system. Drain them both.

Once that's done, we can get to business.
The way I do things is Top, middle, and then bottom. That refers to where you are regarding workspace on the vehicle.
So for the top, we must remove EVERYTHING that attaches to the engine bay from the engine assembly.
This includes:
-Coolant hoses
-Engine room harness
-Air filter box with intake hoses
-Evap line
-Fuel line
-Both A/C lines to the compressor
-2 Ground straps
-Brake Booster vacuum hose
-2 Heater hoses

First thing I like to do is the air filter boxes with intake hoses, it clears up a lot of space and grants you access to a/c lines etc.
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Here is a picture of the coolant hoses at the top
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Can't forget to recover the a/c system before you pull those compressor lines
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A look at the 2 lines going to the compressor
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Since we are on the driver side, you can remove the ground straps now. 1 is removed from the frame. The other is removed from the engine block.
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Next thing to do is disconnect the Engine room harness. This is next because whats left after the harness is located towards the back and being able to move the harness out of your way is a blessing.
I didn't take a before pic of this, but the battery covers must be removed to gain access to the harness.
Sorry for the bad picture.

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The harness also goes down towards a few connectors and a ecu

馃槺馃槺馃槺馃槺 did not realize we can only attach 10 pics to a thread. I am a noobie to forums. I will attempt to continue this in comment form!
 

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The 10 picture limit is only per post I think, with that said someone give this mans thread a sticky!
 

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2004 G35, 2019 Nissan NV200
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Discussion Starter #3
The harness also goes down to a few connectors and a ECU
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Ok now the Evap line, located towards the pas rear of the engine bay
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Once that is out of the way, you can remove the brake booster hose
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And then finally, the heater hose for the pas side
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Don't forget the heater hose to the driver side!
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Now the fuel line. Located at the pas front of the engine bay. Just unclip that yellow portion and pull up. Some fuel may come out but don't be alarmed.
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Ok i thinks that's it for the top. I usually life it up to waist level and work the wheel well portions next.
The steering knuckle and lower control arm stay with the subframe. We will disconnect the suspension at the upper ball joint and sway bar end links. The brake caliper will also stay with the frame. Dont forget to remove those, i didnt take a picture of that step. So Starting with the upper ball joint
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Make sure to remember there is a speed sensor on the knuckle that must be removed
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Then the top half of the sway bar end link. Which doubles as the bolt to the shock.
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Now the bottom half of the sway bar end link. Removing this nut will allow you to pull the end link out.
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Thats pretty much it for suspension and the wheel area. Except when you do the driver side, do not forget the steering gear linkage. And always mark the 2 in a way that will allow you to assemble it back at the same mating surfaces you removed them from. Forget to do this and you will have a serious alignment issue.
 

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2004 G35, 2019 Nissan NV200
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Discussion Starter #4
Thats pretty much it for suspension and the wheel area. Except when you do the driver side, do not forget the steering gear linkage. And always mark the 2 in a way that will allow you to assemble it back at the same mating surfaces you removed them from. Forget to do this and you will have a serious alignment issue.
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Ok now that this middle section is taken care or, we can work on the bottom side!
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Not the best picture I know...
Now comes the exhaust system (from the cat back) and the drives haft
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The gear shifter linkage that goes from the shifter to the transmission just Has a 12mm nut, cant forget that. I forgot to edit this picture with a red label but you should be able to see it
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Now that we have the bulky stuff out of the way, just a few more little things and down goes the sub frame.
Let's move to the trans cooler lines that go to the radiator. There are only 2
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I forgot to take a pic. But obviously disconnect the lower radiator hose at the radiator. This next harness is for the steering system. If you're equipped with dast you will have 2 connectors at each wheel well. This electric system only has 1 and its located on the driver side wheel well. Just follow that harness that goes along the front of the subframe to it.
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Ok now its time to lower the subframe! Prepare the table!
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You must position the vehicle and the table to your preference. I prefer to keep the vehicle some what low, so that I can grab a stool and look at the top for anything that I may have forgot to disconnect as I lower the subframe. Usually every few inches I will take a peek at the engine bay.

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Once the table is in place, you can remove the sub frame bolts. There are only 6 total. I took pictures of 3. The other 3 are on the same spot, opposite side.
Starting with the rear of the sub frame.
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Move up about half way
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Now the front
 
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Discussion Starter #5
Now the front.
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Now just remove the 3 on the other side. But wait! There is more!
The transmission is still secured to the frame. There are 4 bolts to the trans mount that remain. Then the assembly will be ready to drop.
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Ok now we can lower the engine and transmission assembly. The picture makes it look like a swift drop, but like I said, I will periodically inspect everything to.make sure nothing is catching. I suggest you do the same.
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At this point, we can raise the vehicle and have FULL access to the exhaust system, including the turbos.
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Front view, idk why because we don't touch it but her it is.
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Ok now to business.
First thing we need to do is remove the sensor on the turbo and the heat shield. This turbo is of the newer part number, its been updated so the exhaust gas temperature sensor has already been deleted.
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Now
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Ok now to remove the cats
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All it takes to remove them is the turbo band and the brackets holding the cats.
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Sorry I forgot to circle again. But there are 2 brackets.
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With that gone we can move to the turbo. This style of turbo doubles as the manifold so the turbo literally mounts to the head. It also has the waste gate installed as 1 assembly from the factory. So we will replace them as an assembly. There are a few coolant lines and vacuum lines and a connector for the electric waste gaye that must be removed.
 

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Discussion Starter #6
With that gone we can move to the turbo. This style of turbo doubles as the manifold so the turbo literally mounts to the head. It also has the waste gate installed as 1 assembly from the factory. So we will replace them as an assembly. There are a few coolant lines and vacuum lines, oil feed lines, and a connector for the electric waste gaye that must be removed.
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The mounting bolts and for some reason I circled a coolant line and an oil feed line. Well they all need to be removed.
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And thats it!
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Here is the old turbo. Sorry, not much visual defect to see. This turbo wasn't replaced for an oil leak but for a faulty waste gate. (1st time I've seen 1 go bad)
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There are a few parts that must be swapped over to the new turbo. And also the new turbo will not come with an exhaust gasket. DO NOT forget to install one. Or you will regret it.
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And there it is!! Installation is the same steps, just reversed! Except I will say that the intercooler cooling system needs to be bled manually.

I hope this helps somebody out there, or at least will be enjoyed by a reader. It took a lot more effort than I expected to create this thread. And I should have documented the process more with more pictures but the "hustle" started taking over as I was eager to finish this car and move to the next.

Any questions, you can comment below or pm me. Thanks!!
 

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Absolutely awesome and much appreciated! (y)
 

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Wow, that is some serious wrenching !! I wouldn't even dream of attempting to do this, but it makes for a great read and is good info for future use/other purposes. Thanks for posting !!
 
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Fascinating. I will never, ever, attempt a repair such as this - but I enjoyed all the detail!

What were the symptoms that identified the waste gate needing replacement?
 
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I can also understand wanting more pictures and it being hard to document every little thing while trying to get the job done. I always try to take as many pictures as possible when I put together service/rework kits for the factories or dealerships, but the real work begins with the markups and explanations.

Also I think you did a good job on the explanations. I think the hardest part is trying to convey the procedure to someone else who has no experience in the process. Especially hard when you just got done eating, drinking, and breathing it and might skip the minor things that you would naturally do without a second thought.

Thanks for the great read!
 
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Sweet! Really glad you joined the forums 馃憤
 

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2017 Q50 Red Sport 400 RWD
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Ummm.... speechless.

Let me help you rename the thread title:

How To: Replace turbos on the 3.0

-------->

How To: Convince yourself to let the Professionals Replace Your turbos on the 3.0
 

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Fantastic write up sir, we can tell a lot of effort went into this!
 

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Great write up and pics. One tip, you really should make step 1 to disconnect the battery. You're disconnecting ground straps to the block and messing with the factory harness. You do not want to risk arcing during this lengthy process.
 

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I think another thing missing here is the wastegate relearn process via Consult. At least 99% of us here don't have access to Consult. But these are all good info!
 

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2018 Q50 Red Sport 400 AWD
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This is a good example of why bean counters should not have their way on every little cost savings debate during the engineering design process.

I'm curious @MobileTechGundam , how many hours of labor from beginning to end of this job? And once disassembly has made it to this point, is there anything else you would replace "just in case" if this were your car you were working on?

One final thought...tile and grout floor in a service shop??????

Thanks for the time and effort you put into educating us. A "vehicle lift" and a "lift table"...those two tools will rule out 100% of us unless someone is a professional mechanic.
 

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This is a good example of why bean counters should not have their way on every little cost savings debate during the engineering design process.
Agreed, sometimes its literal penny's saved on parts that end up costing thousands in repairs. Heck one of the most annoying repairs I had to do on my G37 was replacing the cheap plastic tabs on the brake pedal that depressed/released two switches behind the pedal.

Broke them when bleeding my brakes and it effectively put my car in limp mode and forced my tail-lights to stay on, I could only image what would have happened if that broken during a panic stop on the highway. They were soon replaced with steel bolts for $2 so I'd never have this problem again. Hah
 
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