Engine mounting bolt torque

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7698
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Joined: Tue May 01, 2018 7:00 am
Name: TailWheelCharlie
Location: UK
Aircraft Type: C120 - GAKVM
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Engine mounting bolt torque

Post by 7698 »

Can anyone advise on the torque settings for the AN6 bolts holding in a C85 please...
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6643
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Joined: Tue May 01, 2018 7:00 am
Name: John C
Location: KLCI, NH
Aircraft Type: 1946 C140/C90
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Re: Engine mounting bolt torque

Post by 6643 »

For -8 and -12 engines with conical rubber mounts, Continental recommends the following:
"Install a slotted nut on each mount bolt, and tighten all nuts to 60-80 inch pounds torque. This is very important, since insufficient tightness will allow excessive vibration, whereas too much tightening will deform the rubber bushings."

Cessna specifies a steel tube around the bolt and inside the bushing that Continental does not. I'd still use the same torque even if you are using them as most of the ones I've seen have been crushed by over tightening.

If you have a -14, -16 or O200 engine with Lord style mounts, the Continental recommendation is "tighten each nut to 180-190 inch pounds torque."
7698
Posts: 70
Joined: Tue May 01, 2018 7:00 am
Name: TailWheelCharlie
Location: UK
Aircraft Type: C120 - GAKVM
Occupation-Interests:
Contact:

Re: Engine mounting bolt torque

Post by 7698 »

Thanks John.. :)
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