Hello, my name is XXXXX XXXXX X have an answer to your question regarding your Volvo exhaust manifolds and elbows.
If the manifolds mount onto studs, the final torque value for the manifold bolts is 42-44ft/lbs. If they mount with bolts bolts it would be 46-48ft/lbs. There are two sequences...For the first, set your torque wrench at 26ft/lbs and start with the two center bolts, working outward to the next two each side of the middle ones, and then the two outer most. Now set your wrench to the correct final torque value and run the sequence again and your done. Be sure and use new OEM or better quality gaskets(same goes for the elbows too).
The torque value for the elbow bolts is about 38ft/lbs and should be run in two sequences as well using a lesser torque setting for the first sequence. For these bolts you just alternate diagonally across from each bolt several times as you cinch it down. It's always a good idea to apply anti-seize compound to all bolts and studs during assembly.
I hope this helps answer your question. Please feel free to write me back with any additional questions or concerns . If you feel my answer was helpful please use the accept button to accept my answer so that I would be paid for my time. Thanks, XXXXX XXXXX opportunity to try to answer your question.
Hi Frank, The main reason for re-torquing the bolts is due to the metallic gaskets used by most mfgs. Because they have a tendency to expand and contract, it is possible for them to loosen a little but not likely. If you want to check them just to make sure then just set your torque wrench at 42-48ft/lbs(depending on whether it's studs or bolts) and run the sequence I described in my last post.
If your friend lives in a climate where it freezes in winter then remind him he needs to drain the manifolds and heat exchanger as well as the block when winterizing.
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