So to sum up for our non technical members then:
open deck block is not a cause of structural weakness and promotes coolant circulation between block/head
high performance and or high load application's such as the Freelander need the thermostat moving to the cylinder head coolant outlet
the crankshaft is not dynamicaly balanced beyond 6500 RPM in standard form and is responsible for block flex' when extended
The stresses within the block sandwich are spread and managed by the design of the stretch through bolts
the bolts are designed to be torqued up and stretched to put the bolt into it's yield zone, so the bolt flex's with the block
liner to block deck stand proud height has increased from 3-4 thou to 4-5 thou
block machined faces will go out of tolerance over time as the heating cycle works manufacturing stresses out of the block
the plastic dowel caused head shuffle, resulting in the liner tops no longer sitting in the gasket fire ring, steel dowel re-introduced
early gaskets suffered failure of the elastomer used in the fire rings and oil feed orifices [not discussed but added to complete the picture]
early damp liner engines suffered from excessive manufacturing tolerances between the block and liner
Fitting a beefed up through bolt not operating in it's yield or elastic zone will result in the crank seizing in it's journals or the block cracking
The above conclusions are based on high performance engines fitted to light weight racing applications.
What are the conclusions to be drawn from the above for those of us running standard Rover designed damp and wet liner engines?
Fitting the modified oil rail and beefed up bolts plus MLS gasket is probably not necessary with wet liner engines. Always change the through bolts when replacing the head gasket. Making the block too stiff when it was designed to flex could be detrimental to engine long life?
Liner heights need to be carefully measured before rebuild.
The Ford designed upgrade to oil rail, MLS gasket and beefed up through bolt's seems at odds with the conclusion drawn above that crankshaft dynamic imbalance is responsible for excess block flex.
Please don't view this as a lecture by myself and feel free to offer your opinion if you think I've got part or everything wrong?
