Voyager 1 and 2 observations have been used to derive the energy spectrum of 'anomalous' cosmic ray (ACR) helium using a technique based on the separation of the isotopes of He. Previously reported observations show that the ACR oxygen spectrum underwent a change in shape following the solar magnetic field reversal in 1980; in this paper we present evidence for a corresponding change in the ACR helium and oxygen and galactic cosmic ray (GCR) 4He and 3He can be reproduced both before and after the field reversal using a simple solar modulation model in which the effects of curvature and gradient drifts are arbitrarily neglected.