I am replacing the gaskets on my exhaust. I tried to research what the proper torque value is for the 5/16-18 nuts that hold the exhaust stacks onto the cylinder exhaust port studs. A lot of people were confusing the stud torque value with the nut torque value. In any case, I didn't have much confidence in what I was reading since the values were ranging from 160 - 210 in. lbs.
A Lycoming service limits and torque recommendation manual listed 160-180 in. lbs. and technicians from Mattituck, ECI, and Aircraft Engines Inc. are listing 204 in. lbs.
It seems over torquing these nuts would be very problematic due to the heating and cooling cycles, as well as potential warping to the exhaust stack flange which would result in an exhaust leak.
My inclination is to start with 160 in. lbs. and see how it goes before increasing the torque.
Can anyone speak from experience here on what would be the best technique?
Thanks,
Glenn
A Lycoming service limits and torque recommendation manual listed 160-180 in. lbs. and technicians from Mattituck, ECI, and Aircraft Engines Inc. are listing 204 in. lbs.
It seems over torquing these nuts would be very problematic due to the heating and cooling cycles, as well as potential warping to the exhaust stack flange which would result in an exhaust leak.
My inclination is to start with 160 in. lbs. and see how it goes before increasing the torque.
Can anyone speak from experience here on what would be the best technique?
Thanks,
Glenn
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