Cummins ISX15 Air in Coolant Problem

We made a conclusion that the reason of this is a pitted or cracked cylinder liner in the lower part. This would explain all the symptoms. We removed the oil pan and pressurized the cooling system. Leakage has been detected from cyl.1
Today will remove the cylinder head and will see the details.

 

Turned out that the issue is a blown cylinder gasket. Right before we dismantled the oil pan the symptoms intensified drastically giving us a fountain from the coolant tank.
An inframe has been done 200K ago. Liners has been changed. No significant pitting on them. Liners protrusion is nominal. Need to check the head surface for bend. The head bolts were tightened differently. The once from the center of the head produced a noise when untightened contrary to the ones on the sides which were not as tight.
Due to the coolant in the 1st cylinder we are going to change the liner and assemble everything back.

 

Sorry for the wrong terminology.
I loaded the cylinder with the tool tightening the bolts with 138 lb-ft (if I remember it correctly) and using the dial indicator checked at 6 points the distance between the surface of the block and the top surface of the liner. On cummins specs it stated it must be within 0.1-0.3 mm while not more than 0.05 mm difference between the adjacent cylinders and mot more than 0.1 difference between any of the cylinders.
I would not do any repair works it I didn’t know how to do the stuff.
During the previous repair they must made a cut of a cylinder seat since I found an extra service shim in addition to a captive shim.
My readings showed 0.25mm - 0.29mm for all the liners.
Did I make anything wrong here? @Goodysnap

 

Went for a short family trip, will take a look on Sunday-Monday and will let you know. Will measure both shim thickness at 6 points and inspect counterbore