28439-ZV7-003 Spacer - Overview. The 28439-ZV7-003 Spacer is a critical OEM part within the Honda marine engine system, designed to provide precise spacing and alignment for associated components. This spacer helps maintain the structural integrity and optimal functionality of the marine engine system by ensuring parts fit cleanly and operate smoothly without interference. Designed and manufactured to meet Honda's exacting factory dimensions and tolerances, the spacer supports reliable engine pe