The Ford Barn - View Single Post - Nylock self locking nuts on main bearing bolts?

rotorwrench · 06-08-2020, 05:14 PM

If ARP makes a nut that fits and is appropriate for engine internals, I'd use them. Marsden nuts are likely strong enough as long as they are a good grade that would be appropriate. Ford hardware seemed to always be appropriate for the task even if it is antiquated.

Aircraft engines generally use very high grade hardware for the con rods. They are stretch torqued on the higher performance engines and have no locking feature but then at the torque level they are on, they don't need a locking feature. They are even copper plated for corrosion resistance on the Lycoming engines. The engine case forms the main bearings and they use very large through bolts with very hard nuts for torque up.

06-08-2020, 05:14 PM	#13
rotorwrench Senior Member Join Date: Jun 2010 Location: San Antonio, Texas Posts: 16,425	Re: Nylock self locking nuts on main bearing bolts? If ARP makes a nut that fits and is appropriate for engine internals, I'd use them. Marsden nuts are likely strong enough as long as they are a good grade that would be appropriate. Ford hardware seemed to always be appropriate for the task even if it is antiquated. Aircraft engines generally use very high grade hardware for the con rods. They are stretch torqued on the higher performance engines and have no locking feature but then at the torque level they are on, they don't need a locking feature. They are even copper plated for corrosion resistance on the Lycoming engines. The engine case forms the main bearings and they use very large through bolts with very hard nuts for torque up.