Volvo XC90 2004 Thermostat T40 Torx Bolts

[volvoxc90]

I have been completing reassembly of a new thermostat housing assembly on my 2004 XC90, 6 cyl turbo and there are a couple issues I have not been able to resolve regarding bolt torque.

Having purchased the thermostat housing unit from my Volvo dealer, and myself having a version of the VADIS program, I am still not able to locate any specific torque values for the housing assembly, base unit attachment to the block. The bolts I am talking about are not those of the outer thermostat housing cover, I know the values for those and these bolts are already pre-torqued as part of the assembly.

The bolts that attach my housing assembly unit to the block are T-40 Torx bolts and I am not able to locate a torque value for these bolts. I am aware of some generic torque values for M5, M6, M7, etc... and other bolts, just nothing specific to these Torx bolts.

Let alone trying to get a torque wrench into the area, next to impossible, how have some of you addressed this problem in your experiences, tightening the thermostat housing unit to the block?

Do you actually torque these or do you use the method, wrench till bolt seats, then 1/4 - 1/2 turn additional, you get the idea?

Thanks for your help.