LB7 Drivers Side Head Gasket Replacement & Turbo Removal

[Bill Brayman]

I have torn down a LB7 diesel on my 2002-Chev K3500 PU for the purpose of replacing all the injectors, injector sleeves, and head gaskets. My source for removal/installation procedures are the 5 factory books/manuals from Chev, the Diesel Page/members/duramax/ LB7 Fuel Injector Replacement Article and the Diesel Page/members/duramax Head Gasket Replacement Article. I have removed all the ducts, hoses, valve covers, etc and the removal of the injectors. I have stumbled into a big problem. The drivers side intake manifold's bolts are inaccessible because of the turbo charger. I have tried to remove the turbo charger but the back bolts are very tight and I can not get a wrench or socket on the 12 sided bolt heads / no room. Also the small flex underside exhaust duct bolts are very difficult to remove.
My question #1: Do I have to remove the engine from the vehicle in order to get to the bolts to remove the turbocharger? The turbo charger is blocking my access to the left & right sides intake manifold bolts which is necessary before removing the head to replace the head gasket...
My question #2: Is it possible to open the turbo charger up (into two pieces) at the 6" dia clamp while unbolting the bottom two bolts holding the duct to remove the turbo and get to the intake manuifold? I have removed the three big bolts that hold down the turbo bottom feet but the turbo does not want to come loose.
Can anyone help me resolve the problem about the removal of the Turbo in order to get to the intake manifolds and final head removal and gasket replacement?

[Kennedy]

When doing a project like you are into I prefer to do one of 2 ways:

1) Remove engine and do the job on an engine stand

2) Lift the cab and have complete access to engine using the frame as an engine stand.


It's just no fun when you have to lean over and have suck limited access to bolts and viewing.

To answer your question about splitting the turbo yes I have done this, but it is not easy. The turbo drain bolts are probably the hardest part. I did mine several times to do parts swaps several years back. I took a 12mm wrench and bent about 90° and added an extension handle to get the drain bolts.

[More Power]

The GM service manual indicates the turbo has to come off first, but I've spoken to GM mechanics who told me the turbo can remain in place when doing head gaskets.

I've also talked to mechanics who recommend what John does - remove the cab or pull the engine... These recommendations likely come about because of the use of ARP head studs, which does make it harder due to clearance issues with the firewall. Soaking any rusty hardware overnight with a product like WD-40 is a common recommendation.

Jim

[9365turbo]

I didnt remove the turbo when I replaced my head gaskets on my 02 lb7

[9365turbo]

check this page out. http://www.mastertechmag.com/pdf/2009/november/200911mto_gmcduramax.pdf