Rare -electron derived heavy-fermion properties of the solid-solution series LaCuRuTiO were studied for by resistivity, susceptibility, specific-heat measurements, and magnetic-resonance techniques. The pure ruthenate () is a heavy-fermion metal characterized by a resistivity proportional to at low temperatures . The coherent Kondo lattice formed by the localized Ru 4 electrons is screened by the conduction electrons leading to strongly enhanced effective electron masses. By increasing titanium substitution the Kondo lattice becomes diluted resulting in single-ion Kondo properties like in the paradigm -based heavy-fermion compound CeLaCuSi [M. Ocko {\em et al.}, Phys. Rev. B \textbf{64}, 195106 (2001)]. In LaCuRuTiO the heavy-fermion behavior finally breaks down on crossing the metal-to-insulator transition close to .