  We present a new 5-GHz global-VLBI image of supernova 1986J, observed in 2014
at $t=31.6$ yr after the explosion, and compare it to previous images to show
the evolution of the supernova. Our new image has a dynamic range of ~100 and a
background rms noise level of 5.9 $\mu$Jy beam$^{-1}$. There is no significant
linear polarization, with the image peak being $<$3% polarized. The latest
image is dominated by the compact central component, whose flux density is now
comparable to that of the extended supernova shell. This central component is
marginally resolved with a FWHM width of $900_{-500}^{+100} \; \mu$as,
corresponding to a radius of $r_{\rm comp}=6.7 _{-3.7}^{+0.7} \times 10^{16}$
cm for a distance of 10 Mpc. Using VLBI observations between 2002 and 2014, we
measured the proper motions of both the central component and a hot-spot to the
NE in the shell relative to the quasar 3C66A. The central component is
stationary to within the uncertainty of 12 $\mu$as yr$^{-1}$, corresponding to
570 km s$^{-1}$. Our observations argue in favor of the central component being
located near the physical center of SN 1986J. The shell hot-spot had a mean
velocity of 2810+-750 km s$^{-1}$ to the NE, which is consistent with it taking
part in the homologous expansion of the shell seen earlier. The shell emission
is evolving in a non-selfsimilar fashion, with the brightest emission shifting
inwards within the structure, and with only relatively faint emission being
seen near the outer edge and presumed forward shock. An animation is available.
