We present optical , IR and millimeter observations of the solar-type star 13-277 , also known as GM Cep , in the 4 Myr-old cluster Tr 37 .
GM Cep experiences rapid magnitude variations of more than 2 mag at optical wavelengths .
We explore the causes of the variability , which seem to be dominated by strong increases in the accretion , being similar to EX-or episodes .
The star shows high , variable accretion rates ( up to \sim 10 ^ { -6 } M _ { \odot } /yr ) , signs of powerful winds , and it is a very fast rotator ( V sini \sim 43 km/s ) .
Its strong mid-IR excesses reveal a very flared disk and/or a remnant envelope , most likely out of hydrostatic equilibrium .
The 1.3 millimeter fluxes suggest a relatively massive disk ( M _ { D } \sim 0.1 M _ { \odot } ) .
Nevertheless , the millimeter mass is not enough to sustain increased accretion episodes over large timescales , unless the mass is underestimated due to significant grain growth .
We finally explore the possibility of GM Cep having a binary companion , which could trigger disk instabilities producing the enhanced accretion episodes .