I have a 2005 TB EXT. I replaced the head at 170K miles. At about 179K miles, it hit a classic case of a spun rod bearing on #3. I was just going to replace the bad connecting rod, crank including main and rod bearings, and rings, but after inspecting the cylinder walls I think I need to have them bored out. The bearings shavings did some damage. There are some very strange dig marks in the top end of cylinder walls and also a very strange stain on #6 that looks like a water jacket was leaking into the cylinder ???. Has anyone bored out and I6 without re-sleeving? I've called a few machine shops in the area and they have never worked on one of these blocks before which seems weird. I really wish I could just buy a short block because I just replaced the head, but now one seems to sell a short block.
Issues with boring the I6 .020 over?
- Thread starter brosenquist
- Start date
xavierny25
Member
m.mcmillen
Member
They do sell oversized pistons but the sleeves that are in there are already very thin. I don't remember where I read it but, someone had a machine shop start boring one and the sleeve started spinning in the block when they tried to bore it out.
littleblazer
Member
- Jul 6, 2014
- 9,265
What he said. Generally sleeved blocks end up being resleeved or exchanged in my experience.
I agree that for a faster ...but perhaps not an absolutely certain outcome that you will wind up getting a decent, serviceable, Low Mileage Engine Block that has NOT been All Beat to BupKas… Follow @cornchip & @littleblazer ’s suggestions and just find a Complete, Low Mileage Engine to replace the FUBARed One you have now.
But… it you want to know all about what is actually involved in performing a Complete Engine Block Overhaul with an On Topic Focus that answers all of your questions ( and then some ) about how this can be done… Visit THIS Link… and read from around Post #132 all the way down to around Post #142. This information will demystify The Procedures, The Tools and The additional Components that you would need to possess in order to completely recondition your Engine Block by installing All Brand New Cylinders in your Engine:
https://gmtnation.com/forums/threads/engine-swap-2004-for-2002-gm-atlas-4-2l-motor.15786/page-4
By the way… The ‘Stock as a Clock’ Cylinder Wall thickness… Right off the GM factory floor… is a mere 1.5 MM. Hence… there is not a lot of ‘meat’ to work with when boring them out in say... the usual “0.030 Over” ...which translates into being 0.762 MM ...or even when just honing out what appear to be ‘usable cylinders’. The other advantage of performing this Upgrade and Revitalizing work is that your New Cylinders will then be able to use the OEM Mahle Pistons in the Stock Bore Size.
These Centrifugally Molten Iron Manufactured, Cast Iron Cylinders are available from Melling for around $20 a Piece… and are finished to the point of only requiring a light, 400 Grit-Ball Stone Nodule Plateau Hone to be able to accept a Brand New Set of Stock Pistons and Rings. Melling also has an ORDER FORM that you can use to submit that should include all of the dimensions you require for your build… and they will Custom Make the Set to your liking as well... if you don’t like the flavor they sell as the OEM Stock Cast Iron Cylinder Sleeves for this Motor.
The only point of contention I would make about this particular repair… is that as long as you possess Good Mechanical Skills and some Critical Thinking when Following the Exact Procedures, The outcome of doing this will return the Block to its OEM condition. The Special Tool Set is of a very High Quality and is a Breeze to use. The Removal of the Old Cylinders and Installation of the New Ones is very straightforward, requiring no need to either Heat Up the The Engine Block ...or Chill the Cylinders and No Adhesives are required during their Installation.
All of the Tool Set Sub-species WILL need to be used to finish the installation by bolt-mounting a 1.6 HP DeWALT Drill Driven - Special Cutter Device that will literally shave down the Flange Tops above All of the Cylinders to just above Flush with the Upper Surface of the Engine Block. If You watch all of the videos in the link above… You’ll get a Better Idea of How these Tools Work… and then you can decide if all of this additional Time, Effort and Expense will be worth the trouble.
Anyhow… If you like being Challenged by the GM LL8 4.2L Engine as a Mechanic... It simply does NOT get any harder to do than this task demands because it MUST be done RIGHT...(6) Times in a Row. Bear in mind that my approach to the doing of the “Cylinder Honing OFF of the Block” Activity required a bit of 'Invention and Adventures in Wood-Working' to allow me the chance to perform this Task more like a Machine Shop would do the work… and eliminate the possibility of contaminating the ‘innards’ of the Engine with Metal Particles, and Abrasive Honing Detritus.
THAT portion of this R&R was (is) NOT an absolutely essential approach… but it was one I preferred doing ...with the idea of Using an Abundance of Caution and a desire for achieving uniformity with the 45 Degree Hash Line on the Cylinder Walls to improve the New Rings Seating and Sealing inside of all the Cylinders. My work on this Engine Build continues; albeit ...often in Fits and Starts and sometimes... at a Snail’s Pace.
Best of Luck with All Your Repairs. :>)
But… it you want to know all about what is actually involved in performing a Complete Engine Block Overhaul with an On Topic Focus that answers all of your questions ( and then some ) about how this can be done… Visit THIS Link… and read from around Post #132 all the way down to around Post #142. This information will demystify The Procedures, The Tools and The additional Components that you would need to possess in order to completely recondition your Engine Block by installing All Brand New Cylinders in your Engine:
https://gmtnation.com/forums/threads/engine-swap-2004-for-2002-gm-atlas-4-2l-motor.15786/page-4
By the way… The ‘Stock as a Clock’ Cylinder Wall thickness… Right off the GM factory floor… is a mere 1.5 MM. Hence… there is not a lot of ‘meat’ to work with when boring them out in say... the usual “0.030 Over” ...which translates into being 0.762 MM ...or even when just honing out what appear to be ‘usable cylinders’. The other advantage of performing this Upgrade and Revitalizing work is that your New Cylinders will then be able to use the OEM Mahle Pistons in the Stock Bore Size.
These Centrifugally Molten Iron Manufactured, Cast Iron Cylinders are available from Melling for around $20 a Piece… and are finished to the point of only requiring a light, 400 Grit-Ball Stone Nodule Plateau Hone to be able to accept a Brand New Set of Stock Pistons and Rings. Melling also has an ORDER FORM that you can use to submit that should include all of the dimensions you require for your build… and they will Custom Make the Set to your liking as well... if you don’t like the flavor they sell as the OEM Stock Cast Iron Cylinder Sleeves for this Motor.
The only point of contention I would make about this particular repair… is that as long as you possess Good Mechanical Skills and some Critical Thinking when Following the Exact Procedures, The outcome of doing this will return the Block to its OEM condition. The Special Tool Set is of a very High Quality and is a Breeze to use. The Removal of the Old Cylinders and Installation of the New Ones is very straightforward, requiring no need to either Heat Up the The Engine Block ...or Chill the Cylinders and No Adhesives are required during their Installation.
All of the Tool Set Sub-species WILL need to be used to finish the installation by bolt-mounting a 1.6 HP DeWALT Drill Driven - Special Cutter Device that will literally shave down the Flange Tops above All of the Cylinders to just above Flush with the Upper Surface of the Engine Block. If You watch all of the videos in the link above… You’ll get a Better Idea of How these Tools Work… and then you can decide if all of this additional Time, Effort and Expense will be worth the trouble.
Anyhow… If you like being Challenged by the GM LL8 4.2L Engine as a Mechanic... It simply does NOT get any harder to do than this task demands because it MUST be done RIGHT...(6) Times in a Row. Bear in mind that my approach to the doing of the “Cylinder Honing OFF of the Block” Activity required a bit of 'Invention and Adventures in Wood-Working' to allow me the chance to perform this Task more like a Machine Shop would do the work… and eliminate the possibility of contaminating the ‘innards’ of the Engine with Metal Particles, and Abrasive Honing Detritus.
THAT portion of this R&R was (is) NOT an absolutely essential approach… but it was one I preferred doing ...with the idea of Using an Abundance of Caution and a desire for achieving uniformity with the 45 Degree Hash Line on the Cylinder Walls to improve the New Rings Seating and Sealing inside of all the Cylinders. My work on this Engine Build continues; albeit ...often in Fits and Starts and sometimes... at a Snail’s Pace.
Best of Luck with All Your Repairs. :>)
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Hey all.. thanks for the input. I was mulling my options and was pretty much set on purchasing a rebuilt long block.
BUT I went to pick n pull yesterday to get some parts for another car and happened upon a wrecked 04 TB that someone had already pull the trans, front diff, and BOTH CX axles. The engine turned over freely and was complete. So I took that as a sign and pulled the short block. So far I've pulled the pan and all looks good. I think I'm just going to throw a ring kit, a new timing set, and replace the main seals on this block and use my freshly rebuild head. New TTY bolts of course.
I'll make sure to look it over real good before reassembling. Is there anything in particular I should checkout. I've seen some of @MRRSM articles and videos on how to check for a warped crank and such, but I'm not sure if that's needed here since the engine turns over quite nicely.
BUT I went to pick n pull yesterday to get some parts for another car and happened upon a wrecked 04 TB that someone had already pull the trans, front diff, and BOTH CX axles. The engine turned over freely and was complete. So I took that as a sign and pulled the short block. So far I've pulled the pan and all looks good. I think I'm just going to throw a ring kit, a new timing set, and replace the main seals on this block and use my freshly rebuild head. New TTY bolts of course.
I'll make sure to look it over real good before reassembling. Is there anything in particular I should checkout. I've seen some of @MRRSM articles and videos on how to check for a warped crank and such, but I'm not sure if that's needed here since the engine turns over quite nicely.
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I should NOT steer you towards my Two Tomes on this subject for anything other the First Two Pages of "The 85,000.00 Engine ...." Thread to find the OEM Part Numbers and maybe a few suggestions here and there... (Talk about Long and "BORING"'...) But you would be wise to find the major Posts by @m.mcmillen and @Mooseman for your Engine Rebuild procedures. 'The Legendary Mac' has the Three Most Important things in his favor that will make all the difference to you:
(1) The Skill and "Mechanic's Chops" to do the work.
(2) The Hands-On Experience with the Tear Down and Re-Build of the LL8 Engine.
(3) Complete Success with the Outcome!
BOL2UB
(Best Of Luck To You, Brother)
(1) The Skill and "Mechanic's Chops" to do the work.
(2) The Hands-On Experience with the Tear Down and Re-Build of the LL8 Engine.
(3) Complete Success with the Outcome!
BOL2UB
(Best Of Luck To You, Brother)