MerCruiser Closed Fresh Water Cooling Systems
Monitor Closed Fresh Water Cooling System Video's & Tip's
What's the term "Fresh Water" refer to? This is a common question we get with customers looking to buy MerCruiser Closed Fresh Water Cooling Systems. PPT's high capacity OEM designed Closed Cooling Systems offer several inherent advantages versus standard aftermarket marine cooling systems. These advantages include:
Advantages of Monitor Closed Cooling Systems
- C12200 Copper Construction.
- High Capacity Tube Bundle (higher tube-count than standard).
- 6 Raw Water passes which yields higher water velocities, higher film coefficients, and therefore higher overall efficiencies.
- Knife edged dividers for reduced leakage.
- Dual Action Thermostat which allows maximized coolant flow during the entire engine operating range, regardless of thermostat position.
- Full flow coolant flow strategy which means thermostat bypassing is not utilized thereby ensuring full coolant flow thru the exhaust system as well as desirable operating temperatures when idling in cold water conditions.
- 160 Degree operating temperature for maximized spark & fueling by the engine management system.
Related MerCruiser Cooling System Parts
- MerCruiser Cooling Hoses
- MerCruiser Cooling Hoses & Boat Parts
- MerCruiser Cooling System Flush
- MerCruiser Cooling System Schematic
- MerCruiser Cooling System Flow Chart
Fresh Water Cooling Tech Articles
San Juan Closed Freshwater Cooling Systems
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San Juan Engineering & MFG CO. began producing Closed Cooling systems well over 30 years ago. They offer cooling systems for Mercruiser, Volvo Penta & OMC Sterndrive and Inboard engines that cover a wide range of different Inboard and Sterndrive Boat Models. Their Fresh Water Cooling systems are built on the specified design requirement of each individual boat's engine package which is based on the model year and layout of the engine. These systems are packaged and sold complete to ensure you the quickest and simplest installation possible. When you buy one of these San Juan Closed Cooling Systems you will not only receive the Heat Exchanger, Complete Thermostat Housing Assembly but the Mounting Brackets, Hoses and Gaskets as well. All of San Juan's Closed Cooling Systems also come supplied with a parts list and detailed installation instructions. All of there systems are built using Industry Recommended C12200 Copper which San Juan stands behind with a 12 month limited warranty. Performance Product Technologies has been selling San Juan Cooling Systems since 2002 and offers our customers the most extensive Technical Library with numerous tip's, articles and How-To Video's. |
3.0L Models | ||
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MC301 | Mercruiser 3.0L 4 Cylinder GM Engines both 120/140 Hp models. Remote Mounted Freshwater Cooling Kit for Years 1968-present.This is a 1/2 system which Cools the Engine Block only. If/When replacing an old unit please specify freshwater hose sizes. 1-1/2" to 1-1/4" or 1-1/4" to 1-3/4". |
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MC327 | Mercruiser 3.0 LX Inline 4 Cylinder Engines w/ V Belts, Years 1997-19991/2 System, Side Mounted Freshwater Cooling Kit |
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MC333 | Mercruiser 3.0 LX Inline 4 Cylinder Engine Models w/ Serpentine Belt, Years 2000-2004. 1/2 System Freshwater Cooling Kit Which Cools the Engine Block Only, Side Mounted |
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MC342 | Mercruiser 3.0 LX Inline 4 Cylinder Engines w/ Serpentine or V-Belts, Years 2005-2012 Side Mounted 1/2 System Freshwater Cooling Kit Which Cools the Engine Block Only. Specify if "Turn Key Start"No Catalytic Converted |
6 Cylinder Models | ||
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MC307 | Mercruiser 165 225 Cu-In Inline 6 Cylinder GM Engine ModelsFull System Freshwater Cooling Kit Which Cools the Engine Block & Exhaust Manifolds |
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MC319 | Mercruiser 4.3 LXH GM V6 Engines w/ Serpentine Belt Year 1996-19991/2 System Freshwater Cooling Kit for Vortec (8 Bolt Intake Manifold) GEN+ Engines w/ One Piece Exhaust Manifold ONLY. Cools the Engine Block Only and Will Not Fit EFI Engine Models. For EFI Models Substitute MC-320. This Cooling System will NOT Fit if Vapor Separator is Located on the Starboard Head. |
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MC321-6 | Mercruiser 4.3L V6 GM Engines w/ Serpentine Belt, Year 1997-2001Full System Freshwater Cooling Kit which Cools the Engine Block and Exhaust Manifolds. Fits EFI/TBI Motor Models. NO Inboard or V-Drive Motor Models. If the 4.3L has a Remote Oil Filter, this Filter Must be Relocated. |
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MC331-6 | Mercruiser 4.3L V6 EFI Engines w/ Serpentine Belt, Years 2000-20011/2 System Freshwater Cooling Kit Which Cools the Engine Block Only. On the EFI & Carbureted Engine models, the Alternator Location Must be on the Starboard Side. |
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MC336-6DJ | Mercruiser 4.3L V6 MPI Engines w/ Serpentine Belt & Dry Joint Exhaust, Years 2002-20111/2 System Freshwater Cooling Kit Which Cools the Engine Block Only. SPECIFY IF Engine is 2005 or 2006 |
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MC341 | Mercruiser 4.3L V6 Carbureted GM Engines w/ Dry Joint Exhaust, Years 2002-2011Full System Freshwater Cooling Kit Which Cools the Engine Block & Exhaust Manifolds. Raw Water Inlet Hose Routing Must go Over Top of the Front/Port Side of the Engine. SPECIFY IF 2005 or Above |
Small Block V8 Models | ||
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MC305 | Mercruiser 898/228/260 Small V8 for 1970 to 1983 Engine ModelsFreshwater Cooling Kit for Rear High Rise Exhaust. This is a Full System Which Cools the Engine Block & Exhaust Manifolds. If the Power Steering Pump is Mounted on the Port Cylinder Head, This Kit Cannot be Used Unless Power Steering Pump is Relocated. |
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MC306 | Mercruiser 188/233 Small V8 FORD Engine ModelsFull System Which Cools the Engine Block & Exhaust Manifolds. |
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MC308 | Mercruiser 225/228 305/350 Small V8 GM Engine Models Full System Freshwater Cooling Kit Which Cools the Engine Block and Exhaust Manifolds for Large Rear High Rise Exhaust Models. If the Power Steering Pump is Mounted on the Port Cylinder Head, This Kit Cannot be Used Unless Power Steering Pump is Relocated. |
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MC320 | Mercruiser 4.3/5.0/5.7 GM Based Engines w/ Serpentine Belt, Year 1997-20011/2 System Freshwater Cooling Kit Which Cools the Engine Block Only. Fits Engine Models w/ Port Side Mounted Alternator Only. Will Not Fit if Vapor Separator is Located on the Starboard Head. No Inboards or V-Drive Models. |
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MC321 | Mercruiser 5.0/5.7 V8 GM Engines w/ Serpentine Belt, Year 1997-2001Full System Freshwater Cooling Kit which Cools the Engine Block and Exhaust Manifolds. This System Fits EFI/TBI Engine Models. NO Inboard or V-Drive Models. If the Engine is an Magnum MPI Specify This When Ordering as Additional Special Parts are Required. Fits Model w/ Port Side Alternator Only. |
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MC325 | Mercruiser 5.7 EFI/MPI 350 V8 GM Engines w/ Serpentine Belt, 1997-20011/2 System Freshwater Cooling Kit which Cools the Engine Block Only. Fits Inboard & V-Drive Engine Models. Specify Your Engine Model When Ordering. Raw water INLET Must Run Up the Front/Port Side of the Engine. |
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MC326 | Mercruiser 5.7 EFI 350 V8 GM Engines w/ Serpentine Belt 1997-20011/2 System Freshwater Cooling Kit which Cools the Engine Block and Exhaust Manifolds. Will Also Fit 1999 Magnum & 2000 5.0L EFI Throttle Body. Fits Inboards but this must be specified when Ordering. Raw water INLET must run up the front/port side of the engine. |
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MC326-VD | Mercruiser 5.7 EFI/MPI 350 V8 V-Drive Engines w/ Serpentine Belt, 1997-2001Freshwater Cooling Kit Cools Engine Block and Exhaust Manifolds. Will Also Fit 1999 Magnum & EFI Throttle Body. Fits V-Drives. Specify your Engine Configuration when Ordering. The Raw-Water INLET must run up front/port side of the engine. |
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MC328OE | Mercruiser 4.3/5.0/5.7 V6 & V8 Engines, Years 1982 & Up1/2 System, Remote Mounted (Stringer or Deck Mounted) Freshwater Cooling Kit which Cools the Engine Block Only. For Tight Installations with Limited Space |
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MC331-8 | Mercruiser 5.0L/5.7L V8 EFI Engines w/ Serpentine Belt, Years 2000-20011/2 SystemFreshwater Cooling Kit Which Cools the Engine Block Only. On the EFI & Carbureted Engine models the Alternator Location Must be on the Starboard Side. |
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MC336-8DJ | Mercruiser 5.0/5.7/6.2 MPI Engines w/ Serpentine Belt & Dry Joint Exhaust, Years 2002-20111/2 System Freshwater Cooling Kit Which Cools the Engine Block Only. NO Inboards or V-Drives.SPECIFY IF :2005 or 2006 |
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MC338 | Mercruiser 4.3/5.0/5.7 V6 & Small V8 Carbureted GM Engines, Year 2002 Only1/2 System Freshwater Cooling Kit Which Cools the Engine Block Only w/out Dry Joint Exhaust. Raw Water Inlet Hose Routing Must go Over Top of the Front/Port Side of the Engine. |
Big Block V8 Models | ||
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MC310 | Mercruiser 1982-1992 330/454 Big Block V8 GM Engine ModelsFull System Freshwater Cooling Kit which Cools the Engine Block and Exhaust Manifolds for use on Engine Models with Center Rise Style Exhaust. Customers Need to Specify Whether their Engine is Equipped w/ or w/o Power Steering When Ordering. |
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MC311 | Mercruiser 7.4 454/502 Displacement GM Engines 1993-1997 w/ V BeltsFull System Freshwater Cooling Kit for Bravo Sterndrive Models. Cools the Engine Block & Exhaust Manifolds. Specify when ordering if EFI, MPI, or Magnum, (this is important as different parts are required). |
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MC324 | Mercruiser 7.4 LX MPI V8 Gm Engines w/ V-Belts, 1997Full System Freshwater Cooling Kit which Cools the Engine Block & Exhaust Manifolds. |
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MC329 | Mercruiser 7.4 L-29 MPI Big Block V8 GM Engines w/ Serpentine Belt, Years 1998-20011/2 System Freshwater Cooling Kit which Cools the Engine Block Only. Specify if Magnum as Additional Parts are Required. |
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MC330-454 | Mercruiser 7.4L 454 MPI V8 GM Marine Engines w/ Serpentine Belt, Years 1998-2001Full System Freshwater Cooling Kit Which Cools the Engine Block & Exhaust Manifolds. Specify When Ordering if the Engine is a Magnum model as Additional Parts are Required. |
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MC330-502 | Mercruiser 8.2L 502 MPI V8 GM Marine Engines w/ Serpentine Belt, Years 1998-2001Full System Freshwater Cooling Kit Which Cools the Engine Block & Exhaust Manifolds. Specify When Ordering if the Engine is a Magnum model as Additional Parts are Required. |
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MC335 | Mercruiser 7.4L V8 Big Block GM V-Drive Engines w/ V Belts, Years Early 90'sFull System Freshwater Cooling Kit Which Cools the Engine Block & Exhaust Manifolds.The Raw Water Inlet Hose Must be Routed on Top of The Engine & Over the Valve Cover. No MPI or Magnums. |