LS Engine Parts and Accessories - Cooling Systems

LS Sea Pump Assembly
Your Price:
$895.99

GM LS Series Engine Single Stage Sea Water Pump

625-4116

Hardin Marine is the first to bring a engine specific sea water pump for the popular LS series of engines. This single stage sea water pump was designed around the 5.3 ,6.0, and 6.2 liter generation engine platforms. The pump uses Hardin Marine's Extreme Lifetime Series stainless steel impeller housing as well as a proprietary short body construction that allows the necessary access or clearance for the engines factory engine mounting pads when the pump is installed. The pump is designed to mount to the engine blocks factory A/C mounting bosses while positioning the billet aluminum serpentine pulley in line with OEM crankshaft pulley. The billet mounting bracket provides the two necessary idlers that allow this pump to be incorporated into most factory automotive serpentine accessory drive systems. The Sea pump features female 1" NPT inlet and outlet ports for ease of plumbing convenience.

Note: Fits OEM GM LS Corvette / CTS-V / G8 automotive balancer spacing with 1-1/2" offset (NOT Truck or F-Body balancer)

GM LS Series Engine Dual Stage Sea Water Pump
Your Price:
$1,199.99

GM LS Series Engine Dual Stage Sea Water Pump

625-4117

Hardin Marine is the first to bring a engine specific sea water pump for the popular LS series of engines. This dual stage sea water pump was designed around the 5.3 ,6.0, and 6.2 liter generation engine platforms. The pump uses Hardin Marine's Extreme Lifetime Series stainless steel impeller housing as well as a proprietary short body construction that allows the necessary access or clearance for the engines factory engine mounting pads when the pump is installed. The pump is designed to mount to the engine blocks factory A/C mounting bosses while positioning the billet aluminum serpentine pulley in line with OEM crankshaft pulley. The billet mounting bracket provides the two necessary idlers that allow this pump to be incorporated into most factory automotive serpentine accessory drive systems. The Sea pump features female (2) 1" NPT  and (1) 1-1/4" common inlet and outlet ports for ease of plumbing convenience.

Note: Fits OEM GM LS Corvette / CTS-V / G8 automotive balancer spacing with 1-1/2" offset (NOT Truck or F-Body balancer)

LS Crossover and Thermostat
Your Price:
$399.99

GM LS1 - LS3 Thermostatic Control Crossover Cooling System for Non-Circulating Pump Applications

625-4535

GM LS1 - LS3 Thermostatic Control Crossover Cooling System for Non-Circulating Pump Applications

AT last a cooling system solution for adapting the popular GM LS engine into any Jet Boat or application with an external water pump source. This system allows removal of the Automotive engine mounted water circulation pump and provides both water inlet/outlet and temperature control through the integrated thermostat assembly. Clean, simple, and reliable the perfect solution for retrofitting the LS modern engine into a jet boat or any boat not utilizing the OEM circulating pump.

WARNING**** will not work with Variable Valve Timing covers.


LS Crossover and Thermostat
Your Price:
$389.99

GM LS1 - LS3 Thermostatic Cooling System for Freshwater Sterndrive Applications

625-4530

GM LS1 - LS3 Thermostatic Cooling System for Freshwater Sterndrive Applications

As Hardin Marine continues the quest towards new product development they have designed an easy to install thermostatic cooling system for freshwater raw water cooled engine applications. This system allows use of an OEM circulating style water pump and multiple accessory drive kits to to be used while providing the necessary thermostat assembly for temperature control. This is perfect for retrofitting a GM LS based engine into most popular sterndrive engine applications using a sea water pump assembly. Precision CNC machined and anodized satin finish make for an attractive compact fitment. Each unit features a 160 degree thermostat while other heat range thermostats and a bypass hose assembly is sold separately.


Water Circulating Pump 850399-1
Your Price:
$219.99

LS Water Circulating Pump

625-4562K

Water Circulating Pump for LS Engines.


Big Block Chevy Closed Cooling Kit Up To 650HP
Your Price:
$2,199.99

GM LSA Closed Cooling System for Engine and Intercooler

625-458

These are the same coolers OEM Engine manufactures use on their LSA Marine engine conversions. The OEM manufacturer builds their own bracketry and it IS NOT available. So if you plan on buying these units each has a mounting bolt pad but you will need to build YOUR OWN bracketry. If you do not understand closed cooling seek a professional engine builder. There is NOT additional specs available what you see is what we sell we have attached plumbing instructions and some diagrams to assist. They are sold as tanks ONLY for both the engine and the intercooler. Seek a knowledgeable professional for installation.


Big Block Chevy Closed Cooling Kit Up To 650HP
Your Price:
$1,899.99

LS1, LS2, LS3 and LS6 Closed Cooling Kit - Copper / Brass

625-4574

LS1, LS2, LS3 and LS6 Closed Cooling Kit - Copper / Brass

While there are numerous universal OEM closed cooling kits, this is not one of those. This is a true custom engineered and developed closed cooling system designed around new LS1, LS2, LS3 and LS6 applications. The kit is perfect for engines making up to 650 horsepower.

We offer the closed cooling tank version with a pre-primed coat, where you can paint-to-finish. This allows you to customize it to your engine for the ultimate in appearance and durability. This High Performance Closed Cooling kit is designed for applications with horsepower levels to 650HP.

The Kit comes with: Tank, Brackets, Hoses.

NOTE: Will not work with port side mounted sea pumps 625-4116, 625-4117.

These will NOT work with IMCO, MP, or front inlet exhaust systems.
These WILL work with Seaward, Hardin Cyclone, Lightning and CMI exhaust systems


LS Crossover and Thermostat
Your Price:
$159.99

Bypass Hose Kit for GM LS1 - LS3 Thermostatic Cooling System

625-4536

Bypass Hose Kit GM LS1 - LS3 Thermostatic Cooling System 

For use with 625-4530 Thermostatic Cooling System.


LS Crossover and Thermostat
Your Price:
$614.99

Water Inlet Crossover Kit for GM LS Engines

625-4525

Water Inlet Crossover Kit for GM LS Engines

These new adapters and crossover tubes allow easy installation of a remote mounted electric water pump on the GM LS engine. These billet aluminum block adapters feature (4) -12 AN O-ring female ports for routing water to a remote mounted electric water pump. The 1/8" NPT Port can be used to connect to the steam tube plumbing.


LS Crossover and Thermostat
Your Price:
$227.95

LS Steam Tube Kit w/ Stainless Steel Hard Line Tubing

625-4520

LS Steam Tube Kit w/ Stainless Steel Hard Line Tubing

Earl's hard line steam tube kit is designed to eliminate trapped air and steam from your engine to prevent hot spots & overheating. Easy bolt-on installation when used with Earl's pivoting steam vent adapters - part # LS9807ERL (2 sets required). Made from attractive stainless steel tubing & black anodized components.

This steam tube kit works w/ the Holley LS Hi-Ram, Holley Single Plane, and Sniper Fabricated Intake Manifolds for the GM LS Engine.

Features:

  • Steam Tube Kit Eliminates Trapped Air and Steam from Your Engine to Prevent Hot Spots & Overheating
  • Custom Look That is More Attractive than Original Equipment (OE) Hard Lines
  • Use w/ Adjustable Pivoting Steam Vent Adapters for Easy Installation
  • Four Corner Style - Allows Flow of Steam & Coolant from Front & Back of Cylinder Heads
  • Made from Stainless Steel Tubing & Black Anodized Aluminum Components – for Corrosion Protection & a Great Look
  • Outlet Size - Use w/ 1/4" Hose

Replacement O-Ring for LS1 - LS3 Thermostatic Cooling System
Your Price:
$1.49

Replacement O-Ring for LS1 - LS3 Thermostatic Cooling System

625-1027

Replacement O-Ring for LS1 - LS3 Thermostatic Cooling System 625-4535. Qty. (4) used in application.

These fit the square ports on the base of the unit against the block, and the internal connection between the top cover and base.


Replacement O-Ring for LS1 - LS3 Thermostatic Cooling System
Your Price:
$1.49

Replacement O-Ring for LS1 - LS3 Thermostatic Cooling System

625-1025

Replacement O-Ring for LS1 - LS3 Thermostatic Cooling System 625-4535. Qty. (2) used in application.

These fit the round ports on the base of the unit against the block.


Water Outlet Hose for LS1 - LS3 Thermostatic Cooling System
Your Price:
$29.99

This Part has options, please click the button below to order.

Water Outlet Hose for LS1 - LS3 Thermostatic Cooling System

625-4534

Water Outlet Hose for LS1 - LS3 Thermostatic Cooling System