Complete Closed Cooling Kits - Mercruiser Closed Cooling Kits

This is a standard capacity system design for Mercruiser Chevy based V6 engines 262 CID sterndrive for model years 1985 thru 1997, with V-Belts or Serpentine belt with the low Stbd mounted alternator which ran up until about 1999.

NOTE: Because of adjustability of the MFH-5399 mounting bracket, the hose running past the idler pulley can be brought into contact with the idler pulley if the installer is not paying attention in that area. The MFH-5230 is adjustable in its location and will clear this pulley with no problems. Therefore, although this MFH-5399 kit will fit the serpentine belt engines, care must be taken to ensure that there is a reasonable amount of clearance from the pulley and belts.

Don’t be sold strictly on pricing. The Monitor Standard products have several benefits versus other standard after market systems. This system is based on the high capacity, “OEM” products, even manufactured by the same company that produces the OEM systems for Mercruiser, Volvo Penta, Yanmar, Westerbeke, Polaris, and others. This system utilizes a higher number of cooling tubes, more passes on the sea water portion of the cooler, as well as includes “sealed” dividers. This is the same design technology used by Mercruiser and Volvo Penta on their OEM systems.

Will NOT fit engines with high mounted alternators and/or v-drives. Heat exchanger extends from extreme starboard side of a normal exhaust manifold towards port side clearing most high mounted power steering pumps if any (See above illustration). Plastic expansion tank mounts either on front of heat exchanger or if space is limited on vertical surface next to engine. Full system – Block and manifold. Engine block and exhaust manifold on fresh water system. Exhaust elbows remain on raw water system.

Kit includes heat exchanger, heavy duty translucent plastic expansion tank plus all other components necessary to complete conversion. Some components from engine such as hoses are re-used. Heat exchanger painted black. Brackets and other components painted black or zinc plated. All hose clamps are stainless. Shell and tube type. C12200 all copper alloy construction made to the highest industry standards. Heavy duty dual de-mountable clean out end covers. Zinc anode protection.

NOTE: This system extends about 9″ forward of the center of the water outlet on the intake manifold and 9.50″ above the water outlet gasket surface. That is without the expansion tank mounted to the front of the heat exchanger.

General Maintenance and Warranty Information

You can view or download the full PDF document below:

General Manual rev01

CONVERSION KIT FITS

1985-2001 MerCruiser Chevy based small block V8 engines 305-350 CID both sterndrive and inboard, specifically those engines with alternator mounted low and the power steering pump mounted high both on the port side of the engine. Designed especially for the low capacity raw water pumps used on sterndrive engines. Kit will NOT fit most engines with high mounted alternators, such as late model MerCruiser engines and/or v-drives. Separate kits are available for those engines. Some engines have fuel line routing and fuel filter location that must be slightly changed. Heat exchanger is 3 3/4″ in diameter x 21 3/4″ long and fits within overall length, width, and height of most engine conversions. See above illustrations. Plastic expansion tank mounts either on front of heat exchanger or, if space is limited, on vertical surface next to engine.

COOLING SYSTEM TYPE

Block only. Engine block is on fresh water system. Exhaust manifolds remain on raw water system.

CONVERSION KIT

A kit includes heat exchanger, heavy-duty translucent plastic expansion tank plus all other components necessary to complete conversion. Some components from the engine are reused. Heat exchanger is primed gray. Brackets and other components are finished in black or zinc plated. All hose clamps are stainless steel.

HEAT EXCHANGER

Shell and tube type heat exchanger with special high capacity design. All copper alloy construction made to the highest industry standards. Dual demountable clean out end covers. Zinc anode protection.

COOLING SYSTEM CAPACITY

System will maintain engine temperature in the 160-170oF range using the 160oF thermostat, included in kit. System has a capacity safety margin higher than industry standards.

HEATER SYSTEM HOOKUP

Heaters, such as galley water heaters and cabin heaters, are easily connected to the system by utilizing the cooling system bypass connections.

INSTALLATION TIME

Typical average installation time is approximately one hour, assuming new engine and normal accessibility. Allow additional time for filling and testing. Installation skills are not beyond those of most do-it-yourself boat owners. Complete illustrated installation instructions are included in kit. Ordinary hand tools are used.

WARRANTY

Two year warranty. For complete details see Limited Warranty for Fresh Water Cooling Kits document enclosed with your kit and located on policies page of our website.

Note: All Monitor Products freshwater cooling kits are primer coated and finish coated in matte black.

CONVERSION KIT FITS:

Chevy based big block V8 engines 454-502 CID both sterndrive, inboard and V-drive. Especially designed for the low capacity raw water pumps used on sterndrive engines. Will NOT fit most engines with high mounted alternators such as late model OMC engines. Separate kits are available for those engines. Some engines have fuel line routing and fuel filter location that must be changed slightly. Heat exchanger is 4 1/8″ x 22.5″ long and fits within overall length, width, and height of most engine conversions. Heat exchanger extends from the inside of the starboard exhaust manifold towards port side clearing most high mounted power steering pumps if any. See above illustration. Plastic expansion tank mounts either on front of heat exchanger or if space is limited on vertical surface next to engine.

COOLING SYSTEM TYPE

Block only. Engine block on fresh water system. Exhaust manifolds remain on raw water system.

CONVERSION KIT

Kit includes heat exchanger, heavy duty translucent plastic expansion tank plus all other components necessary to complete conversion. Some components from engine are reused. Heat exchanger and Brackets are finished in black. Hose clamps all stainless.

HEAT EXCHANGER

Shell and tube type. Special new high capacity design. All copper alloy construction made to the highest industry standards. Heavy duty dual demountable clean out end covers. Zinc anode protection.

COOLING SYSTEM CAPACITY

Will maintain engine temperature in the 160-170oF range using 160oF thermostat, included in kit. System has capacity safety margin higher than industry standards.

HEATER SYSTEM HOOKUP

Heaters such as galley water heaters and cabin heaters are easily connected to the system by utilizing the cooling system bypass connections.

INSTALLATION TIME

Very easy installation of approximately one hour assuming new engine and normal accessibility. Allow additional time for filling and testing. Installation skills are not beyond those of most do-it-yourself boat owners. Complete illustrated installation instructions are included in kit. Ordinary hand tools used.

WARRANTY

Two year warranty. For complete details see Limited Warranty for Fresh Water Cooling Kits document enclosed with your kit and located on policies page of our website.

Note: All Monitor Products freshwater cooling kits are primer coated and finish coated in matte black.

This is a High Capacity CLOSED COOLING SYSTEM designed for 1997 Thru 2002 MerCruiser5.0/5.7L V8 engines with serpentine/single belt and NON-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).

This is a High Capacity CLOSED COOLING SYSTEM designed for 2002 Thru present MerCruiser 4.3/5.0/5.7L V6 and 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).

This is a standard capacity system design for Mercruiser Chevy based 4.3/5.0L/5.7L (262, 305, and 350 CID) V6 and V8 sterndrive engine for model years 1985 thru 1999, with V-Belts or Serpentine belt with the low Stbd mounted alternator which ran up until about 1999.(see below for exceptions).

This Heat Exchanger utilizes a copper alloy high performance 6-pass shell and tube design that delivers superior cooling in an efficient and compact package. It has dual removable end covers for easy clean-out. The Installation Kit includes heavy-duty translucent plastic expansion tank, complete instructions, and all other components necessary to convert a raw water cooled engine to Freshwater Cooling. Some existing water hoses and hose clamps are reused. Heat exchanger, thermostat housing and mounting brackets are primed gray. Fasteners are zinc/cadmium plated or stainless steel. All hose clamps are stainless steel.

COOLING SYSTEM TYPE:

This kit is a “full” fresh water cooling [FWC] system; meaning that the engine block and exhaust manifolds are protected by the system. Exhaust elbows remain on the raw water system. System utilizes a unique, high performance heat exchanger. Our FWC systems are specially designed for the low capacity raw water pumps used on sterndrive engines.

MFH-5399 CONVERSION KIT FITS:

MerCruiser Engines:

COOLING SYSTEM CAPACITY:

Will maintain coolant temperatures in the 160-170 F range using 160 F thermostat included in kit. System has cooling capacity safety margin higher than industry standards.

HEATER SYSTEM HOOKUP:

Heaters such as galley water heaters and cabin heaters are easily supplied by utilizing the cooling system bypass connections.

INSTALLATION TIME:

Average installation time is approximately four to six hours, assuming engine has normal accessibility. Allow additional time for filling and testing. Installation skills are typical of most do-it-yourself boat owners. Complete illustrated installation instructions are included in kit.

WARRANTY:

Two year warranty. For complete details see Limited Warranty for Fresh Water Cooling Kits document enclosed with your kit and located on policies page of our website.

Note: Some engines have fuel line routing and fuel filter location that must be changed slightly.

May also fit custom marine conversions:
With v-belt or multi-belt equipped engines.(will not fit serpentine belt equipped engines)
Sterndrive and Inboard engines only. (will not fit V-drive installations)
Kit fits engines with low mounted alternator

Note: All Monitor Products freshwater cooling kits are primer coated and finish coated in matte black.

CONVERSION KIT FITS

MerCruiser Chevy based big block V8 engines 454-502 CID, fits sterndrive, inboard and V-drive. Especially designed for the low capacity raw water pumps used on sterndrive engines. Kit will NOT fit most engines with high mounted alternators such as late model OMC engines. Some engines have fuel line routing and fuel filter location that must be changed slightly. Heat exchanger is 5 1/8″ x 22″ long and fits within overall length, width, and height of most engine conversions. Heat exchanger extends from the inside of the starboard exhaust manifold towards port side clearing most high mounted power steering pumps if any. See above illustration. Plastic expansion tank mounts either on front of heat exchanger or if space is limited on vertical surface next to engine.

NOTE: This system will not fit 454 or 502 Magnum MPI engines. The picture below is a 7.4L MPI (aka L29).

COOLING SYSTEM TYPE

Full system: Engine block and exhaust manifold on fresh water system. Exhaust elbows remain on raw water system. System utilizes a new, unique, high performance heat exchanger, with built in, full flow, bypass control thermostat ensuring optimal jacket and exhaust manifold water flow under all operating conditions.

CONVERSION KIT

Kit includes heat exchanger, heavy duty translucent plastic expansion tank plus all other components necessary to complete conversion. Some components from engine are reused. Heat Exchanger and Brackets are finished in black. Hose clamps all stainless steel.

HEAT EXCHANGER

Shell and tube type. Special new high capacity design. All copper alloy construction made to the highest industry standards. Heavy duty dual demountable clean out end covers. Zinc anode protection.

COOLING SYSTEM CAPACITY

Kit will maintain engine temperature in the 160-170oF range using 160oF thermostat, included in kit. System has capacity safety margin higher than industry standards.

HEATER SYSTEM HOOKUP

Heaters such as galley water heaters and cabin heaters are easily connected to the system by utilizing the cooling system bypass connections.

INSTALLATION TIME

Very easy installation of approximately 1-2 hours assuming new engine and normal accessibility. Allow additional time for filling and testing. Installation skills are not beyond those of most do-it-yourself boat owners. Complete illustrated installation instructions are included in kit. Ordinary hand tools used.

WARRANTY

Two year warranty. For complete details see Limited Warranty for Fresh Water Cooling Kits document enclosed with your kit and located on policies page of our website.

Note: All Monitor Products freshwater cooling kits are primer coated and finish coated in matte black.

This kit is designed to fit 357 Mercury Remanufacturing engines. The system is front mounted at the level of the thermostat housing. This kit is intended for serpentine belt installations. Plastic expansion tank mounts either on front of heat exchanger or if space is limited on vertical surface next to engine.

COOLING SYSTEM TYPE

Full system: Engine block and exhaust manifold on fresh water system. Exhaust elbows remain on raw water system. System utilizes a new, unique, high performance heat exchanger, with built in, full flow, bypass control thermostat ensuring optimal jacket and exhaust manifold water flow under all operating conditions.

CONVERSION KIT

Kit includes heat exchanger, heavy-duty translucent plastic expansion tank plus all other components necessary to complete conversion. Some components from engine are reused. Heat Exchanger and Brackets are finished in black. All hose clamps are stainless steel.

HEAT EXCHANGER

Shell and tube type heat exchanger. Redesigned to achieve a higher cooling capacity. All copper alloy construction made to the highest industry standards. Heavy-duty dual de-mountable clean out end covers. Zinc anode protection.

COOLING SYSTEM CAPACITY

Will maintain engine temperature in the 160-170° F range using 160° F thermostat included in kit. System has cooling capacity safety margin higher than industry standards.

HEATER SYSTEM HOOKUP

Heaters such as galley water heaters and cabin heaters are easily connected to the system by utilizing the cooling system bypass connections.

INSTALLATION TIME

Typical average installation time is approximately three hours, assuming new engine and normal accessibility. Allow additional time for filling and testing. Installation skills are not beyond those of most do-it-yourself boat owners. Complete illustrated installation instructions are included in kit. Ordinary hand tools used.

WARRANTY

Two year warranty. For complete details see Limited Warranty for Fresh Water Cooling Kits document enclosed with your kit and located on policies page of our website.

Note: All Monitor Products freshwater cooling kits are primer coated and finish coated in matte black.

CONVERSION KIT FITS:

1999 – present MerCruiser GM 4.3L, 5.0L and 5.7L (262, 305 and 350 CID) models with a single serpentine belt/single-belt (will NOT fit v-belt or multi-belt equipped engines). Sterndrive and inboard (EXCEPT V-drive installations). For sterndrive applications, the power steering pump should be mounted low on the port side and alternator on the upper starboard side ( For engines with the power steering mounted high on the port side and serpentine belt order kit MFH-5229 or MFH-5398). For inboard applications, the alternator should be located on the lower starboard side of the engine. Heat exchanger is 4-1/8″ diameter x 21″ 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. Plastic expansion tank mounts either on front of heat exchanger or if space is limited on vertical surface next to engine.

COOLING SYSTEM TYPE

This kit is a block only fresh water cooling [FWC] system; meaning that only the engine block is protected by the system. Exhaust elbows and exhaust manifolds remain on the raw water system. System utilizes a unique, high performance heat exchanger. Our FWC systems are specially designed for the low capacity raw water pumps used on sterndrive engines.

CONVERSION KIT

Kit includes heat exchanger, heavy-duty translucent plastic expansion tank, complete instructions, and all other components necessary to convert a raw water cooled engine to FWC. Some existing water hoses and hose clamps are reused. Heat exchanger, thermostat housing and mounting brackets are finished in black. Fasteners are zinc/cadmium plated or stainless steel. All hose clamps are 3XX series stainless steel.

HEAT EXCHANGER

High-flow, shell and tube design allowing a higher cooling capacity than standard. All copper alloy construction made to the highest industry standards. Includes heavy-duty, dual, demountable end covers for easy clean-out.

COOLING SYSTEM CAPACITY

Will maintain coolant temperatures in the 160-170°F range using 160°F thermostat included in kit. System has cooling capacity safety margin higher than industry standards.

HEATER SYSTEM HOOKUP

Heaters such as galley water heaters and cabin heaters are easily connected to the system by utilizing the cooling system bypass connections.

INSTALLATION TIME

Average installation time is approximately 2-3 hours, assuming new engine and normal accessibility. Allow additional time for filling and testing. Installation skills are typical of most do-it-yourself boat owners. Complete illustrated installation instructions are included in kit.

WARRANTY

Two year warranty. For complete details see Limited Warranty for Fresh Water Cooling Kits document enclosed with your kit and located on policies page of our website.

General Maintenance and Warranty Information

You can view or download the full PDF document below:

General Manual rev01