Head nuts
- Thread starter nq50
- Start date
H. L. Chauvin
Well-known member
No.
Tom Wesenberg
Well-known member
Isn't it interesting that with all the castle nuts, lock washers, and safety wire used to keep the nuts in place, the source of all the vibration doesn't use anything but friction to keep the nuts in place. 
J Witt
Well-known member
There's an interesting bit of theory involved with keeping nuts tight that involves stretching the bolts/studs slightly so that an axial load is developed that exceeds the working tensile load on the bolt.
If you do that properly, then the bolt will stay tight. A locking device is rarely used on connecting rods, head bolts, and other such stuff where the material and other design conditions are met which will keep the elastic load on the fasteners.
When I was building Austin Healy Sprite engines, back in the day, we never used the lock tabs that came in the stock engine's con rods. The tabs were too soft and would relax the rod bolt tension by squishing out from under the bolt heads. Likewise, I would never put cotter pins inside a crankcase or other area where there are parts to munch on them.
Lock washers are an invention of the devil.
John
If you do that properly, then the bolt will stay tight. A locking device is rarely used on connecting rods, head bolts, and other such stuff where the material and other design conditions are met which will keep the elastic load on the fasteners.
When I was building Austin Healy Sprite engines, back in the day, we never used the lock tabs that came in the stock engine's con rods. The tabs were too soft and would relax the rod bolt tension by squishing out from under the bolt heads. Likewise, I would never put cotter pins inside a crankcase or other area where there are parts to munch on them.
Lock washers are an invention of the devil.
John
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