In GLM's Mercruiser replacement 4 inch riser, there are two additional water jackets. This allows a higher volume of water to flow through the riser, keeping the engine cooler. *All manifolds and risers are powdercoated black for maximum corrosion protection* **Cast Iron manifolds and risers ...
Manufacturer: GLM Products, Inc. Regular Price:$57.98 Sale Price:$43.99 Sierra Part Number: 18-3320 Mercury Part Number: 46-44292A4 Product Description For MR/Alpha One 1984-1990 Product Photo(s): Image 1 Image 2 This product was added to our catalog on Tuesday 07 November, 2006....