Do you understand when and why a re-torque would be needed to maintain an optimal seal in your joint? Is a re-torque ever not necessary? All of these burning questions and more are addressed in this week’s post.
Re-torque or Not to Re-torque?
1. Typically, when and why do a majority of re-torques need to happen? The best scenario is to re-torque all gaskets after they have seen their first heat cycle. This will provide sufficient loading after the initial relaxation of the part due to heat exposure. Gaskets that NEED to be re-torqued are typically softer construction, with low recovery values and can benefit by being reloaded or re-torqued.
2. Under what conditions would a re-torque not be needed? Stiff gasket materials with good recovery and low creep-relaxation properties such as metal gaskets or high density graphite gaskets would be an example of such items.
3. Are any re-torques ever required beyond the initial one? Typically, no. Further re-torquing will result in crushing of the material beyond it’s designed loading. Most OEM gaskets are designed to be used without re-torquing, as this is not an option on a new engine. Aftermarket parts, however, can often be re-torqued, depending on the application, allowing a more cost-effective material selection to perform adequately.
4. Can multiple re-torques be a sign of a design flaw or gasket issue? It is normally not necessary to re-torque more than once. Ongoing leaks or gasket failure indicate that a better material should be selected in that joint.
5. What are some of the conditions you might observe when it is time for a re-torque? Bolts may be loose or have low retained torque. Also, the gasket may exhibit slight leakage or failure to seal.
Now You Know
We hope this helped clarify any misunderstanding that might be out there regarding re-torquing and its standard practices. It really is very straightforward when it does and does not need to occur, and a lot of it really is material-dependent. If you have any questions or concerns about a specific material, talk to your trusted gasket material supplier.
Until next time!