Mercruiser Closed Cooling System: 2002 - Current Small V8 Carb & Efi *High Capacity* (Premium Full System) (#5320-8B)
Part #: 5320-8B
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This is a High Capacity CLOSED COOLING SYSTEM designed for 2002 Thru present MerCruiser5.0/5.7L V8 engines with serpentine/single belt with DRY JOINT exhaust. System can be utilized on Sterndrive and Straight inboard applications. System will not fit engines with the power steering mounted high on the port side (higher than the valve cover).
If your engine is equipped with exhaust spacers (1.7", 3" or 6") you need to order (2) of the following 27-864547A02 dry joint exhaust gaskets to be used on top of the spacers. Link to Gaskets
Don't make the mistake of being sold strictly on pricing. This particular product is priced slightly higher than other standard after market systems. However, this system is the only "OEM" duplicated product on the market, even manufactured by the same company that produces the OEM systems for Mercruiser, Volvo Penta, Yanmar, Westerbeke, Polaris, and others. Why does this matter? This system utilizes a higher number of cooling tubes, more passes on the sea water portion of the cooler, as well as "sealed" dividers. These systems are also the only after market systems that utilize a bypass style of thermostat which fully flows the engine and exhaust manifolds, even during warmup. What this means from a functional standpoint is that detonation is reduced since steam pockets are prevented from forming due to the high coolant flowrate especially during warmup. This is the same design technology used by Mercruiser and Volvo Penta on their OEM systems. Includes carb, EFI and MPI.
SPACE REQUIREMENTS
Heat exchanger is 4-1/8" diameter x 23-1/2" long and fits within overall length, width, and height of most engine conversions (adds 1-1/2" to overall length of 2001 and newer MPI installations). Heat exchanger extends from extreme starboard side of a normal exhaust manifold towards port side. Plastic expansion tank mounts either on front of heat exchanger or if space is limited it can be mounted on a vertical surface next to engine.Â
To view packaging and installation schematics select the following links;
...5320 Installation Instructions (Opens in a seperate window)
...5320-8b Kit for MPI Engine (Opens in a seperate window)
...5320-8b Kit for Carbureted Engine (Opens in a separate window)
...Schematic Description (Opens in a seperate window)
...Schematic in Color (Opens in a seperate window)
IMPORTANT NOTE 1: If you have a MerCruiser 6.2L, or 383 Mag engine you will need to order the supplemental Magnum Kit. The kit is used to increase flow through the engine and heat exchanger to prevent the engine over-temperature alarm from sounding after running at higher engine rpm and then coming down to idle.......MAGNUM KIT
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