An Etymological Dictionary of the German Language/wälzen
wälzen, vb., ‘to roll, trundle,’ from MidHG. węlzen, OHG. węlzen, walzen (from *walzjan), wk. vb., ‘to roll, turn, trundle’; factitive of walzen, which was orig. only intransit. The Teut. root walt, from Aryan wald, has no cognates in non-Teut.