[Subninja]

Just wondering how many people have actually tackled this job on their own. I don't want to spend the small fortune on having someone else do this and was wondering a couple questions.

1. Any tips would be awesome. So far dropping the subframe seems to be the best way to gain access to this.

2. About how long did it take to complete the project?

3. I plan on draining the oil and coolant but anything else recommended?

4. Did you reuse the drain/feed oil lines again?

5. Did you have to do any coding for the new turbos? I have heard you have to do something with the wastegate but not sure.

6. If you did drop the subframe did you need an alignment afterwards?

7. I plan on buying the install kit from ECS but did you need anything else?

This is a daunting task but I really want to do it myself as I feel I would know the car better afterwards. Thanks for any advice. Also I live in southern Georgia and anyone who would want to help would be awesome. Thanks.

[v1rus]

I wonder about the same thing too. I thought about buying the Bentley service manual expecting to find some useful hints there.

No coding will be required, but you'll probably be better to reset ECU adaptations after you done.
Alignment will be a must after dropping the sub-frame.

[shushikiary]

From bently manual:

EXHAUST MANIFOLDS AND TuRBOCHARGERS
The N54 engine is equipped with two exhaust manifolds each with
an integral turbocharger. A pre-catalytic converter is attached
downstream of each turbocharger. Should the pre-catalyst need
replacing, it is removable and available separately. See Exhaust
Components in this repair group.
Exhaust manifold and turbocharger
(cylinders 1- 3), removing and installing
- Remove both pre-catalytic converters. See Pre-catalytic
converters (turbo) in this repair group.
- Release right side tie rod from steering rack. See 320 Steering and
Wheel Alignment.
- Remove intercooler. See 170 Radiator and Cooling System.
- Drain engine coolant and remove coolant expansion tank. See 170
Radiator and cooling system.
- Remove coolant pump. See 170 Radiator and Cooling System.
- Remove turbocharger vacuum reservoirs. See 130 Fuel Injection.
- Remove air box and air intake duct. See 130 Fuel Injection.
Remove fasteners on oil return line (1) and oil return line bracket (2).
Gently pull oil return line out of engine block in direction of arrow.
<Oil( Working between turbochargers, remove fasteners (1 and 2) and
remove coolant supply lines (3 and 4).
NOTE-
• If necessary grasp coolant supply line flange with pliers to remove.
Do not use pliers on pipes.
<Oil( Remove fasteners (1) at coolant inlet pipe (2) and remove pipe.
Remove coolant return pipe fasteners (1 and 3) and remove return
pipe (4).
NOTE-
• If necessary grasp coolant return line flange (2) with pliers to
remove. Do not use pliers on pipes.
~ Remove fasteners (1) at retaining plate (2). Remove heat shield
fasteners (3).
~ Remove heat shield (1) in direction of arrow. Make sure shield and
coolant pipes are not damaged.
~ Remove fasteners (1) from bracket (2). Lay bracket on top of cylinder
head.
~ Remove oil supply line bracket fastener (1). Remove oil supply line
in direction of arrow.
~ Remove fastener (1) and remove oil supply line.
NOTE-
• If necessary grasp oil supply line flange (2) with pliers to remove.
Do not use pliers on pipes.
Remove exhaust manifold fasteners (1). Detach vacuum hose from
wastegate valve and remove exhaust manifold I turbocharger
towards the top.
NOTE-
• Take care not to damage wastegate valve linkage.
~ If replacing turbocharger, remove fastener (2) for oil supply line (3)
and install supply line on new unit. Always replace graphite gaskets
(1 ).
- Remainder of installation is reverse of removal. Remember to:
• Use new 0 -rings, gaskets and hardware. Coat hardware threads
with anti-seize paste.
• Check and clear fault memory using BMW scan tool.
• Check air intake system for leaks.
• Check exhaust system for leaks.
Tightening torques
Bracket to cylinder head 9 Nm (7 ft-lb)
Coolant supply line to crankcase 9 Nm (7 ft-lb)
Coolant return line to crankcase 8 Nm (6 ft-lb)
Coolant return line to turbocharger 8 Nm (6 ft-lb)
Coolant supply line to supply line 8 Nm (6 ft-lb)
Exhaust manifold heat shield to crankcase 8 Nm (6 ft-lb)
Oil supply line to crankcase 20 Nm (15 ft-lb)
Oil pressure line to turbocharger 8 Nm (6 ft-lb)
Oil return line to crankcase 8 Nm (6 ft-lb)
Oil return line to turbocharger 8 Nm (6 ft-lb)
Turbocharger to exhaust manifold 20 Nm (15 ft-lb)

Turbocharger and exhaust manifold
(cylinders 4-6), removing and installing
- Remove both pre-catalytic converters. See Pre-catalytic
converters (turbo) in this repair group.
- Release right side tie rod from steering rack. See 320 Steering and
Wheel Alignment.
- Remove intercooler. See 170 Radiator and Cooling System.
- Drain engine coolant and remove coolant expansion tank. See
170 Radiator and Cooling system.
- Remove coolant pump. See 170 Radiator and cooling system.
- Remove turbocharger vacuum reservoirs. See 130 Fuel Injection.
- Remove air box and air intake duct. See 130 Fuel Injection.
"'iii{ Remove fasteners on oil return line (1) and oil return line bracket (2).
Gently pull oil return line out of engine block in direction of arrow.
"'iii{ Working between turbochargers, remove fasteners (1 and 2) and
remove coolant supply lines (3 and 4) .
NOTE-
• If necessary grasp coolant supply line flange with pliers to remove.
Do not use pliers on pipes.
"'iii{ Remove fasteners (1) at coolant inlet pipe (2) and remove pipe.
Remove fastener (1) at coolant return line clamp and remove line.
NOTE-
• If necessary grasp coolant return line flange with pliers to remove.
Do not use pliers on pipes.
~ Remove fastener (1) and remove coolant return line (2) and coolant
supply line (3).
NOTE-
• If necessary grasp flange with pliers to remove. Do not use pliers
on pipes.
• Take care not to damage wastegate valve linkage.
~ Remove fasteners (1) at retaining plate (2). Remove heat shield
fasteners (3 and 4).
Carefully swing out heat sh ields (2 and 3) in direction of arrow.
Coolant supply pipe (1) can be removed along with heat shield.
~ Remove fasteners (1) from bracket (2). Lay bracket on top of cylinder
head.
~ Remove oil supply line bracket fastener (1). Remove oil supply line
in direction of arrow.
Remove exhaust manifold fasteners (1) . Detach vacuum hose from
wastegate valve and remove exhaust manifold I turbocharger
towards the top.
NOTE-
• Take care not to damage wastegate valve linkage.
~ f replacing turbocharger, remove fastener (2) for oil supply line (3)
and install supply line on new unit. Always replace graphite gaskets
(1).
- Remainder of installation is reverse of removal. Remember to:
• Use new 0-rings, gaskets and hardware. Coat hardware threads
with anti-seize paste.
• Check and clear fault memory using BMW scan tool.
• Check air intake system for leaks.
• Check exhaust system for leaks.
Tightening torques
Bracket to cylinder head 9 Nm (7 ft-lb)
Coolant supply line to crankcase 9 Nm (7 ft-lb)
Coolant return line to crankcase 8 Nm (6 ft-lb)
Coolant return line to turbocharger 8 Nm (6 ft-lb)
Coolant supply line to supply line 8 Nm (6 ft-lb)
Exhaust manifold heat shield to crankcase 8 Nm (6 ft-lb)
Oil supply line to crankcase 20 Nm (15 ft-lb)
Oil pressure line to turbocharger 8 Nm (6 ft-lb)
Oil return line to crankcase 8 Nm (6 ft-lb)
Oil return line to turbocharger 8 Nm (6 ft-lb)
Turbocharger to exhaust manifold 20 Nm (15 ft-lb)

On non XI models you can remove the pre-cats without removing the sub frame, but on XI models its easiest to drop the sub frame. Remember if you do drop it you must support the engine, and to fully remove it you will have to undo the control arms and power steering rack, it will make somethings easier, however if you remove the passenger side wheel well liner it will help so you can access a lot of those things easier as well. Most of the other things on the above list of things to do there are already DIY's on this site for. Note that you may also have to "tune" the waste gate actuator rods to the right length after you install the turbo, of which there is also a post on the site on how to do that if you need to.

I've done the pre-cats my self, with 2 friends for help it took 6 hours. You'll also need the special "short" socket for the oxygen sensors (oxygen sensor socket). The water pump most people say is a 2 hour job as well if you know what you're doing, the inter cooler is another hour or so, and then make sure you follow the re-fill procedure which you can find on this site if you look up replacing the oil filter housing gasket.

All in all you're looking at, IMO, by your self first time doing all this stuff, 25 hours of work, so know that going in. That's also assuming nothing major goes wrong likes striping a bolt and that you have all the correct tools before hand.

Also, if you're going to all this work, I'd seriously consider some RB turbo's with down pipes and a custom COBB access port tune for the RB's. Might as well pick up 200 wheel torque if you're going to do all that work.

[Bavarian Tech]

1. Any tips would be awesome. So far dropping the subframe seems to be the best way to gain access to this.
Dropping the subframe is a must, Working around it is annoying, and will add hours of unnecessary cussing, if yours in RWD just swing it out of the way, leaving the steering rack connected. AWD subframes can be removed completely from the vehicle alot easier than RWD

2. About how long did it take to complete the project?
It took me 6 hours to do mine, including an hour lunch. Warranty pays 8hrs for RWD. More for AWD obviously. But I also had access to a lift, trans jacks and air tools, etc...

3. I plan on draining the oil and coolant but anything else recommended?
Your going to loose oil when you pull the turbo return lines out of the block so I'd suggest doing an oil change to make sure the oil level is correct. Coolant will go everywhere anyways so might as well flush it.

4. Did you reuse the drain/feed oil lines again?
I replaced both return lines and the feed line. BMW says your to clean the lines whenever you do a turbo job. I've always replaced them or tried to upsell with CP jobs.

5. Did you have to do any coding for the new turbos? I have heard you have to do something with the wastegate but not sure.
Come already adjusted out of the box


6. If you did drop the subframe did you need an alignment afterwards?
I dropped the subframe, but didn't touch the tie-rods. Just removed them along with the control arms from the knuckle. Steering wheel was straight and true. Subframe can only go in one spot, theirs no adjustment possible. I'd personally see no point in an alignment afterwards, your personal choice tho.

7. I plan on buying the install kit from ECS but did you need anything else?
Not familiar with ECS kit but gaskets for the turbos, (Lines, exhaust,coolant pipe gasket. V-clamps,intake grommets, Header nuts ) new bolt for water pump. Downpipe nuts


This is a daunting task but I really want to do it myself as I feel I would know the car better afterwards. Thanks for any advice. Also I live in southern Georgia and anyone who would want to help would be awesome. Thanks.

If you do decided to tackle the, I'd highly suggest u label EVERY bolt you remove. You will have alot. Especially the ones on the block.

[4doorbmwpower]

thanks for the insight. i will be doing a Vargas upgrade walnutshell blast and a bunch of custom work when i return home!

[chris y]

hi
ive just had the turbo 123 replaced on bmw 335 twin turbo and water pump which cost £3355.00 had car back 3 days and had water leak car was sent back to garage and they are saying it was the bung plug damage and they replaced no cost.
i have had car nearly 2 years no problems or leaks
i picked up car and 3 days later only doing 52 miles in it not the power steering has gone car is back in garage and saying i need a steering rack which is another fortune to replace.
the garage are saying its another fault nothing to do with any works they have done.
they tell me when replacing the turbo they removed it from the top of engine and not botton so didnt remove sub frame or anything to do with steering

can anyone give me any advice on the procedure

thanks