MerCruiser 99438A1 4" 470 Heat Exchanger 170hp 4cyl 3.7L 488 165hp 1983-1989 Wiring Harness There are arrows cast on

There are arrows cast on the sides to tell direction

1960: 10020 / 10021 / QD-21 / QDL-21

Long Bolts: 3734594

Widely used in OMC 800 Stringer & Cobra Models 1981-1996 (Chevy GM (V6 & V8 3

32-61997 Vent Hose

MerCruiser 99438A1 4" 470 Heat Exchanger 170hp 4cyl 3.7L 488 165hp 1983-1989 Wiring Harness There are arrows cast onItem Details Freshwater used part Overall good condition, original paint. This part has been tested for leaks and has new gaskets on both ends The Part number for The 4" heat exchanger is 99438A1 Found on all "470" models 1976 1989 Using a 4" heat exchanger, You can upgrade the earlier a 3" heat exchanger (found on the pre 1983 models) to a 4" if you swap the mounting bracket, and some of the hoses. 470 (2 BBL.) MERCURY 224 I L4 1976 1979 470 (2 BBL.)