Originally Posted By: clinebarger
Originally Posted By: 4WD
Originally Posted By: clinebarger
The Timing Chain Tensioner is activated with OIL PRESSURE!!! If it was bad.....You would KNOW it. You weren't complaining of noise or Camshaft position/correlation trouble codes? There is a special tool that allows removal of the cylinder head without removing the Timing Cover......Kent Moore EN48464, It prevents the tensioner from ratcheting out of place.
Your Balance Shaft chain (If the vehicles was maintained) is probably Okay!!!!
Interesting comment from someone who is clearly a top notch mechanic … watched a couple Canadian mechanics change them without pulling the motor … so I’m puzzled ?
I was a GM Dealer Tech when the 4.2L Atlas engines first came out. I went through all service issue headaches that come with a all new engine design.
First off.....The Altas can be be completely overhauled with the Block in the vehicle, Even the Cylinder Bore Sleeves can be changed! Weather or not it's FASTER to do a "In-Frame" is up for debate?
The Oil Pump is bolted to/part of the front cover, To remove the front cover.....You must first remove the Oil Pan & Pick-Up Tube. Not a big deal on a 2wd model....Quite a bit more work on a 4wd model.
There are NO referencing Timing Marks on the engine ANYWHERE! The ONLY way to cull a Timing Chain is IF the PCM is setting Camshaft Position error codes P0014 &/or P0016.
Now....There are Timing Chain noise issues that can arise from worn out Timing Chain/Guides-Shoes/VTT Phaser Wear/Maxed out Tensioner. Although it's been my experience that this also sets P0014 &/or P0016.
As I stated already (Completely Ignored by most).....Free Play in the Timing Chain with the engine off is 100% normal!!! FACTS sure are pesky problems when they don't fit the narrative.
I have NO clue how the Balance Shafts Chain got brought up in this thread? Other than to "Pile-On" by the OP or the Mechanic/Shop Owner.....Or a combination of all three??
In the end......Using the Kent Moore tool, Having the cylinder head repaired along with some gaskets/head bolts/fluids would have got this truck back into service without a huge bill. I guess that doesn't make for a good DRAMA filled GM bashing thread?
Who is piling on? Wow, what a snowflake.
Again, if you read the GM TSB referenced, there is no repairing the head. It must be replaced.
Sheesh, people can't read these days.