Hi all. Picked up a 05 TB LT. No coolant in oil just starts to blow white smoke after it’s been running a few minutes. Wondering if it’s worth repairing or just grabbing another 4.2 and drop it in?
I6 Blown head gasket
- Thread starter Fishnbob
- Start date
Only if you are willing to do some preparatory Disaster Avoidance on the Donor Engine as follows:
(1) By now... MOST if not ALL Donor Motors will be fairly High Mileage and the chances to do any of these suggestions with some manner of convenience and extreme ease due to open access will disappear the moment the Donor Motor gets Dropped Under The Hood. If you think I'm KIDDING Watch what THIS Dude has to go through:
Uh... NEVER Use Thread Locker on Trapped Fasteners with *Floating Grommets" that only require 89 Inch Pounds of Torque.
If you READ EVERY RELEVANT THING ON THIS SITE BEFORE YOU PROCEED... You will be quite happy with these results.
(2) With the Engine Mounted on an Engine Stand, Pull the Crank-Case Oil Pan and the Front Timing Chain Cover to access the Oil Pan Pick Up Tube and R&R it to REPLACE THE ORANGE GEROTOR PUMP OEM OIL SEAL... and to perform a Lengthy Soak of the Pick Up Screen in a Bucket of Berryman's Chem-Dip to dissolve away all of the Awful Carbon Debris and Baked On Gas Gum Build-Up on that Screen:
(3) Spend the Bread for an OEM Quality Timing Chain Set Kit FROM CLOYES that will include a New Timing Chain, Timing Chain Guides, Timing Chain Tensioner. Replace the Front Timing Cover Seal while the Harmonic Balancer is OFF the front of the Engine.
(4) Pull the Intake Manifold off and replace the Three Pairs of Rubber "O" Ring Gaskets and clean out the upper Intake Ports from the Greasy Carbon and tighten the Trapped Fasteners down to ONLY 89 Inch Pounds. THIS Job alone is VERY Easy To DO B4 The Motor gets installed...and damned near impossible without a LOT of trouble afterwards.
(5) Replace the Valve Train Cover "O" Ring Gaskets and evacuate any Oil/Water from the Spark Plug Wells B4 performing a Plug R&R Inspection.
(6) WITHOUT FAIL...Replace the Old Motor Mounts.
(7) Replace the Water Pump, Serpentine Belt & Tensioner.
(8) Install New recommended ACDelco Spark Plugs.
(9) The OIL Collecting inside the Intake Ports comes from having Excessive Blow By due to the Piston to Cylinder Wear and having the Pair of Upper Compression Rings TRAPPED By Gas Gum. Follow the Threads that Cover filling the Cylinders up with ACDelco Top Engine Cleaner to dissolve the Carbon and Gas Gum Lacquer to allow the *Low Tension* Compression Rings to become FREE again.
If not... the Combustion Gasses and Carbon will continue to pressurize the lower Crankcase and the spaces leading to the underside of the Valve Cover where Motor Oil gets pushed out into the Air Stream through the small Pipe in the Valve Cover and out through the PCV Rubber Tube and eventually into the Intake Manifold.
(10) R&R the Throttle Body and Clean the Carbon-Greasy Dirt from inside. Replace the Rubber Throttle Body Seal.
Remember... Don't get TOO anxious to just DROP that Engine into the SUV... The LAST "Thing" you want to find out is that there is a SERIOUS Engine Problem...AFTER going to the trouble of Swapping in a *Stranger's Motor*.
(1) By now... MOST if not ALL Donor Motors will be fairly High Mileage and the chances to do any of these suggestions with some manner of convenience and extreme ease due to open access will disappear the moment the Donor Motor gets Dropped Under The Hood. If you think I'm KIDDING Watch what THIS Dude has to go through:
Uh... NEVER Use Thread Locker on Trapped Fasteners with *Floating Grommets" that only require 89 Inch Pounds of Torque.
If you READ EVERY RELEVANT THING ON THIS SITE BEFORE YOU PROCEED... You will be quite happy with these results.
(2) With the Engine Mounted on an Engine Stand, Pull the Crank-Case Oil Pan and the Front Timing Chain Cover to access the Oil Pan Pick Up Tube and R&R it to REPLACE THE ORANGE GEROTOR PUMP OEM OIL SEAL... and to perform a Lengthy Soak of the Pick Up Screen in a Bucket of Berryman's Chem-Dip to dissolve away all of the Awful Carbon Debris and Baked On Gas Gum Build-Up on that Screen:
(3) Spend the Bread for an OEM Quality Timing Chain Set Kit FROM CLOYES that will include a New Timing Chain, Timing Chain Guides, Timing Chain Tensioner. Replace the Front Timing Cover Seal while the Harmonic Balancer is OFF the front of the Engine.
(4) Pull the Intake Manifold off and replace the Three Pairs of Rubber "O" Ring Gaskets and clean out the upper Intake Ports from the Greasy Carbon and tighten the Trapped Fasteners down to ONLY 89 Inch Pounds. THIS Job alone is VERY Easy To DO B4 The Motor gets installed...and damned near impossible without a LOT of trouble afterwards.
(5) Replace the Valve Train Cover "O" Ring Gaskets and evacuate any Oil/Water from the Spark Plug Wells B4 performing a Plug R&R Inspection.
(6) WITHOUT FAIL...Replace the Old Motor Mounts.
(7) Replace the Water Pump, Serpentine Belt & Tensioner.
(8) Install New recommended ACDelco Spark Plugs.
(9) The OIL Collecting inside the Intake Ports comes from having Excessive Blow By due to the Piston to Cylinder Wear and having the Pair of Upper Compression Rings TRAPPED By Gas Gum. Follow the Threads that Cover filling the Cylinders up with ACDelco Top Engine Cleaner to dissolve the Carbon and Gas Gum Lacquer to allow the *Low Tension* Compression Rings to become FREE again.
If not... the Combustion Gasses and Carbon will continue to pressurize the lower Crankcase and the spaces leading to the underside of the Valve Cover where Motor Oil gets pushed out into the Air Stream through the small Pipe in the Valve Cover and out through the PCV Rubber Tube and eventually into the Intake Manifold.
(10) R&R the Throttle Body and Clean the Carbon-Greasy Dirt from inside. Replace the Rubber Throttle Body Seal.
Remember... Don't get TOO anxious to just DROP that Engine into the SUV... The LAST "Thing" you want to find out is that there is a SERIOUS Engine Problem...AFTER going to the trouble of Swapping in a *Stranger's Motor*.
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Thanks for all the tips!! Also, I’m thinking I’ll just stick with an I6 instead so I guess it’s best to follow these steps with a “strangers motor” too?
Mooseman
Moderator
Might as well just throw a good used motor in it. Head gasket R&R on these is a major undertaking. The head will require machining and reconditioning and head bolts WILL break in the block and it's usually the ones that are the least accessible in the back. Have seen some where all of them broke. When that happen, it requires a special tool to extract the broken bolts (Time-$ert). You also need some specialized tools like timing chain wedges and a cam retention tool.
This thread is a VERY long read that went through it all and ended in failure.
gmtnation.com
It can be done, have seen a few successfully do it, but the expense of the head work alone makes it more expensive than an engine swap.
Having gone through an engine swap myself on an 02, here are some tips:
- Remove the intake manifold for extra clearance
- Before committing to buying the used motor, take the intake manifold and valve cover off and inspect for coked oil. I didn't do that and mine was poorly maintained. I saw the inside of that motor too many times after with timing and cam phaser issues.
- Replacing motor mounts now is a good idea. Use only ACDelco
- Replace seals, gaskets, water pump, thermostat
- If 4x4, now is a good time to replace the seals of the diff and axles. Open up the disconnect, clean the congealed grease out and repack with a good quality synthetic grease. If damage is found, replace it.
- If 4x4, pull the diff and disco with the engine and swap them onto the replacement engine prior to install
- Keep track of all the connectors, hoses and bolts
- Use 3 feet of extensions to get to the top bellhousing bolts from the rear of the tranny
Either way you go, it's a b!tch of a job!
Edit: Also, for used engines, 02-05 are a direct drop in, 06-07 will drop in with minor modification of the coolant temp sensor wiring. DO NOT TRY TO USE AN 08-09 ENGINE! They will will NOT work with your older PCM.
This thread is a VERY long read that went through it all and ended in failure.
4.2L I6 Head Removal/Engine Restoration
What's up guys, my name's Lee and today I'm going to be starting a new thread based around the wonderful 4.2L's infamous misfiring issue "P0300--". I know the majority of us have all seen the discussions regarding this one particular issue before so I've decided to post my own input on the...
gmtnation.com
It can be done, have seen a few successfully do it, but the expense of the head work alone makes it more expensive than an engine swap.
Having gone through an engine swap myself on an 02, here are some tips:
- Remove the intake manifold for extra clearance
- Before committing to buying the used motor, take the intake manifold and valve cover off and inspect for coked oil. I didn't do that and mine was poorly maintained. I saw the inside of that motor too many times after with timing and cam phaser issues.
- Replacing motor mounts now is a good idea. Use only ACDelco
- Replace seals, gaskets, water pump, thermostat
- If 4x4, now is a good time to replace the seals of the diff and axles. Open up the disconnect, clean the congealed grease out and repack with a good quality synthetic grease. If damage is found, replace it.
- If 4x4, pull the diff and disco with the engine and swap them onto the replacement engine prior to install
- Keep track of all the connectors, hoses and bolts
- Use 3 feet of extensions to get to the top bellhousing bolts from the rear of the tranny
Either way you go, it's a b!tch of a job!
Edit: Also, for used engines, 02-05 are a direct drop in, 06-07 will drop in with minor modification of the coolant temp sensor wiring. DO NOT TRY TO USE AN 08-09 ENGINE! They will will NOT work with your older PCM.
I am guessing you live in Canada somewhere, not sure what else OC could be..
Got a few of our forum members from that neck of the woods, and can lead you in the right direction for good motors, and change over years.
Got a few of our forum members from that neck of the woods, and can lead you in the right direction for good motors, and change over years.
Mooseman
Moderator
OC: Orange County? No OC here AFAIK 
Pull the spark pugs and see if one or two look "washed". Then further confirm by pressurizing the cooling system and look with a borescope for water seeping in.
Are you loosing coolant? A leakdown test may also be useful. While running, look for bubbles coming out of the radiator.
Pull the spark pugs and see if one or two look "washed". Then further confirm by pressurizing the cooling system and look with a borescope for water seeping in.
Are you loosing coolant? A leakdown test may also be useful. While running, look for bubbles coming out of the radiator.
I thought it meant Ontario, CA...
Commyfornia ehh? I jest.. Cause I live in Commyfornia Lite (Colorado)!
Not a lot of active members out that way, but we should be able to handle it!
Yes Commyfornia. I’ll be moving from here in 2 years when I retire to Henderson NV. Getting bad there too but not as bad as Newsomland