The deck can be machined ...../ This said, there are .010" thicker gaskets available.
Sooooooooooooo....You can machine off .010" from the decks.
I personally have cheated a bit and taken the decks down .015"
There are Multilayer stainless gaskets available (Order to what you need...within reason)
These gaskets do not work well on the 6.2 and 6.5 platform....likely because of the few head bolts in the design of these engines.
Taking off .015" will usually do the trick for SLIGHT erosion of the fire ring, but a big gouge is gonna be a serious issue...likely rendering the block unusable.
Hope this helps.
(1) 1995 Suburban 2500 4x4
(1) 1997 Astro
(1) 2005 Suburban (Papa Smurf)
THIS IS BOW TIE COUNTRY
Yes, the block must be completely stripped, frost plugs, drain plugs, oil pressure valves, oil squirts, etc. Some try to get away with a minimal strip and it too often comes back for a bite. Measure the deck height BEFORE you remove the OEM pistons. Both sides. Robyn can chime in why that is SO important.
See whether a 6.5 gasket moves the fire-ring out far enough to miss the gouge.
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Sad tale of woe....
Several years ago I had a 95 Dahooley Crew cab 4x4
It had a sordid past and was on it's second engine (GOODWENCH) YES WENCH
After having it a few years it started losing coolant.
No pressure in the hoses....no leaks visible.
Then one day I yanked the dip stick out.....Whoa....about 2 inches over full and a sloppy gray mess.
Yanked the engine out and tore into it.
Early 506 large outer main bolt block with the large (Early) oil squirt nozzles.
Block had cracked through the #3 main web at the squirt hole....crack went up into the lower part of the block until is ran into the water jacket.
Game over....JUNK
Scared up a "Crack free" 599 block.
The block was bare when I got it.
Tanked it, bored it for .020" over pistons and decked it .015"
Sweeeeeeeeet
Not so much
Started dropping pistons in and OH $hit.....Pistons on one side were hanging out the top of the cylinder by about .040"
This sucker had been decked to the max and we cleaned up plus a bit.
Much hand wringing and vile language ensued......
Finally discovered "Cometic" multi layer head gaskets
I ordered a custom gasket for the one side and used a Fepro +.010" on the other side.
Only one side had been cut the first time and the block was not stamped at the lifter box rail area.
Put the engine together with this combo.
Things worked well for about a year.....then it started leaking combustion gases at the MLS gasket
The 6.5 does not do well with these gaskets....Not enough bolts and clamping force.....
Picked up a real deal AMG block with unfinished cylinder bores.
We bored the holes out to use the .020 OS slugs from the first build....and the rods, crank and most everything else.
The plot thickens.
Dropped the crank in and started to plastigauge the mains.....ZERO CLEARANCE
The mainline was mis-machined.
Long story short.
The AMG engine line had a FUBAR and a bunch of blocks had an error in the main line.
The Kahooonas at AMG wanted them all sent back to the foundry and melted.
Many did not make it that far and ended up on ebay and other spots..
I got the block from a shop in Portland Oregon..
Sooooooo
I measured the mainline and then took the block to a local shop and had them line hone the mainline to the proper size.....
I spoke with AMG officials about the block.....it was an AMG block and other than the mains being .0025" too small....it was perfect.
The management did not want to mess with sending the blocks out to have the mainline fixed ("TOO RISKY" THEY MIGHT GET LOOSE WAS THE THOUGHT)
Well they did anyway......
I fitted the block with a set of AMG heads.
A real cluster to say the least.
Measure the piston to deck with the pistons at TDC.
Should be from .000" to .002" above the deck stock if memory serves.
You can machine up to .015" off the deck and use the .010" thicker Felpro
Do not go more than .015"
Good luck .....
(1) 1995 Suburban 2500 4x4
(1) 1997 Astro
(1) 2005 Suburban (Papa Smurf)
THIS IS BOW TIE COUNTRY