Field removable bonnet assemblies for use with valves are disclosed. An example internal valve includes an internal valve body and a field removable bonnet assembly. The field removable bonnet assembly includes a body that is to be removably coupled to the internal valve body and a shaft to be at least partially positioned within the body. The field removable bonnet assembly also includes an adjuster including a first adjuster portion and a second adjuster portion. The body defines a bore having a first diameter portion and a second diameter portion larger than the first diameter portion. The first diameter portion is to receive a valve packing. The second diameter portion to be threadably engaged by the second adjuster portion. The adjuster is externally accessible to adjust the first adjuster portion within the first diameter portion to change a force exerted by the valve packing on the shaft.