Okay, I know it was dumb….

[Rivets]

Most machinists drill and tap cast iron dry, no lubricant. Basis for this is that cast iron contains graphite which acts like a cutting fluid. Those who use a lubricant, use a very light out one, ex. kerosene.

 

[Hammermechanicman]

Pretty sure cranks are cast steel not cast iron. I use tap magic cutting fluid for drilling and tapping.

 

[Fish]

Wouldn't a Predator engine have metric bolts?

 

[Rivets]

Forged steel, not cast, started dying out in the 50’s and was replaced by iron. Most of the time they were made of grey iron, which is much easier to machine than the other types of iron.

 

[StarTech]

Wouldn't a Predator engine have metric bolts?