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Oil Coolers - Tube Style Oil Coolers

Oil Cooler - 2" Diameter, 8" Length, 1" NPT Connection
Your Price:
$109.99

Oil Cooler - 2" Diameter, 8" Length, 1" NPT Connection

620-150

Oil Cooler - 2" Diameter, 8" Length, 1" NPT Connection

This cooler features thirty-one 1/4" cooling tubes with displacement baffles. It also has 3/8" NPT oil connections with an 1/8" NPT drain. Operating pressure of up to 150 PSI. Designed for power steering or transmission applications.


Oil Cooler - 2" Diameter, 8" Length, 3/4" NPT Connection
Your Price:
$109.99

Oil Cooler - 2" Diameter, 8" Length, 3/4" NPT Connection

620-125

Oil Cooler - 2" Diameter, 8" Length, 3/4" NPT Connection

This cooler features thirty-one 1/4" cooling tubes with displacementbaffles.  It also has 3/8" NPT oil connections with an 1/8" NPTdrain.  Operating pressure of up to 150 PSI.  Designed for powersteering or transmission applications.


Oil Cooler - 2" Diameter, 8" Length, 1-1/4" Hose Connection
Your Price:
$89.99

Oil Cooler - 2" Diameter, 9" Overall Length, 1-1/4" Hose Connection

620-100

Oil Cooler - 2" Diameter, 9" Overall Length, 1-1/4" Hose Connection

This cooler features thirty-one 1/4" cooling tubes with displacement baffles. It also has 3/8" NPT oil connections with an 1/8" NPT drain. Operating pressure of up to 150 PSI. Designed for power steering or transmission applications.


Replacement Oil Cooler Thermostat 190-210 Degree
Your Price:
$79.99

Replacement Oil Cooler Thermostat 190-210 Degree

620-701

Replacement Oil Cooler Thermostat 190-210 Degree

This is a replacement thermostat for use in Hardin Marine Tube Style Oil Coolers.

Tube Style Engine Oil Control Kit Up To 700HP
Your Price:
$1,079.99

Tube Style Engine & Power Steering Oil Control Kit Up To 700HP

620-850

  • For Gen 5/6 BBC Applications.
  • 3" x 25" Oil & Power SteeringCooler with Polished Brackets.
  • 6' of Push-Loc Hose included.
  • Includes 625-7704 Thermostatically Controlled Engine Block Adapter.
  • Includes 6 Straight and 6 90 Degree Fittings for installation.
  • For Gen 4 BBC Applications, Part Number 625-7918 must be ordered as well.

Tube Style Engine Oil Control Kit Up To 700HP
Your Price:
$1,029.99

Tube Style Engine Oil Control Kit Up To 1000HP

620-825

  • For Gen 5/6 BBC Applications.
  • 3" x 24" Oil Cooler with Polished Brackets.
  • 6' of Push-Loc Hose included.
  • Includes 625-7704 Thermostatically Controlled Engine Block Adapter.
  • Includes 6 Straight and 6 90 Degree Fittings for installation.
  • For Gen 4 BBC Applications, Part Number 625-7918 must be ordered as well.

Tube Style Engine Oil Control Kit Up To 700HP
Your Price:
$995.99

Tube Style Engine Oil Control Kit Up To 700HP

620-800

  • For Gen 5/6 BBC Applications.
  • 3" x 16" Oil Cooler with Polished Brackets.
  • 6' of Push-Loc Hose included.
  • Includes 625-7704 Thermostatically Controlled Engine Block Adapter.
  • Includes 6 Straight and 6 90 Degree Fittings for installation.
  • For Gen 4 BBC Applications, Part Number 625-7918 must be ordered as well.

Oil Cooler - 2" Diameter, 16" Length, 1" NPT Connection
Your Price:
$129.99

Oil Cooler - 2" Diameter, 16" Overall Length, 1" NPT Connection

620-350

Oil Cooler - 2" Diameter, 16" Overall Length, 1" NPT Connection

Featuring thirty-one 1/4" cooling tubes with displacement baffles! Large 3/4" NPT oil connections for increased flow with an 1/8" NPT drain. Rated operating pressure up to 150 PSI. Recommended for engines up to 425 horsepower.


Oil Cooler - 2" Diameter, 16" Length, 1-1/4" Hose Connection
Your Price:
$109.99

Oil Cooler - 2" Diameter, 16" Overall Length, 1-1/4"Hose Connection

620-300

Oil Cooler - 2" Diameter, 16" Overall Length, 1-1/4" Hose Connection

Featuring thirty-one 1/4" cooling tubes with displacement baffles! Large 3/4" NPT oil connections for increased flow with an 1/8" NPT drain. Rated operating pressure up to 150 PSI. Recommended for engines up to 425 horsepower.


Oil Cooler - 2" Diameter, 16" Length, 3/4" NPT Connection
Your Price:
$129.99

Oil Cooler - 2" Diameter, 16" Overall Length, 3/4" NPT Connection

620-325

Oil Cooler - 2" Diameter, 16 Overall Length, 3/4" NPT Connection

Featuring thirty-one 1/4" cooling tubes with displacement baffles! Large 3/4" NPT oil connections for increased flow with an 1/8" NPT drain. Rated operating pressure up to 150 PSI. Recommended for engines up to 425 horsepower.


Combination Engine Oil & Power Steering Or Transmission Cooler
Your Price:
$229.99

Combination Engine Oil & Power Steering Or Transmission Cooler

620-400

Combination Engine Oil & Power Steering Or Transmission Cooler, 2" Diameter, 19" Overall Length, 3/8" NPT P/S and 3/4" NPT Oil Connections, 1-1/4" Water Connection

All the same features as our other coolers except it is designed as a MerCruiser replacement cooler for the most common V8 engines. The only noticeable difference is the use of 3/4" NPT oil connections providing a higher volume flow capacity.

Note: Never use small than a 3/4" NPT oil connection on engine coolers.


Combination Engine Oil & Power Steering Or Transmission Cooler
Your Price:
$229.99

Combination Engine Oil & Power Steering Or Transmission Cooler

620-450

Combination Engine Oil & Power Steering Or Transmission Cooler, 2" Diameter, 18" Length, 3/8" NPT P/S and 3/4" NPT Oil Connections, 1" NPT Water Connection

All the same features as our other coolers except it is designed as aMerCruiser replacement cooler for the most common V8 engines.  The onlynoticeable difference is the use of 3/4" NPT oil connections providing ahigher volume flow capacity.

Note:  Never use small than a 3/4" NPT oil connection on enginecoolers.


Hi-Performance Combination Power Steering & Engine Oil Cooler, 3" Diameter, 25" Length, 3/4" NPT Oil Connections, 3/8" NPT Power Steering Connections, 1" NPT Water Connection
Your Price:
$419.99

Hi-Performance Combination Power Steering & Engine Oil Cooler

620-650

Hi-Performance Combination Power Steering & Engine Oil Cooler, 3" Diameter, 23" Overall Length, 3/4" NPT Oil Connections, 3/8" NPT Power Steering Connections, 1" NPT Water Connection

Have you made some performance modifications and you're now making mega horsepower only to find out your stock Mercury cooler can't keep up? Well not only is this our most popular combination cooler, it is also the answer to getting those oil temperatures back down where they belong. This cooler features seventy-six 1/4" seamless cooling tubes and can handle form 450 to 750 horsepower applications with ease. With a 23" overall length, 3/4" NPT oil connections, 3/8" NPT P/S connections, and 1" water connections, this is the perfect solution.


Hi-Performance Engine Oil Cooler
Your Price:
$269.99

Hi-Performance Engine Oil Cooler

620-550

Hi-Performance Engine Oil Cooler, 3" Diameter, 16" Overall Length, 3/4" NPT Oil Connections, 1" NPT Water Connection

Designed for engines making 450 horsepower and above.  These units have seventy-six 1/4" seamless tubes - over double that of a 2" cooler.  The cooler incorporates cast end caps, NO cheap press-formed caps are used.  Operating pressure up to 150 PSI.  This is the cooler all others try to imitate but can never duplicate.  Compare features and you will demand Hardin Marine oil coolers.


Hi-Performance Engine Oil Cooler
Your Price:
$399.99

HP Engine Oil Cooler 3" Diameter, 25" Overall Length, 1" NPT Connection

620-575

H/P Oil Cooler, 3/4" NPT Oil connections, 1" NPT Water Connections, 3" Diameter x 25" Overall Length.

High performance 3" diameter oil coolers (above) are designed for engines making 450 HP and up. These units have seventy-six 1/4" seamless tubes and operate at 150 psi.


Big Block Chevy Gen 4 Bolt-On Cooler, 5" X 14-3/4" Length
Your Price:
$529.99

Big Block Chevy Gen 4 Bolt-On Cooler, 5" X 14-3/4" Length

260-OC401

Big Block Chevy Gen 4 Bolt-On Cooler, 5" X 14-3/4" Length

This Olsen hi-performance engine oil cooler has a unique feature - it bolts directly to the engine block and requires no additional oil plumbing It merely sandwiches between the oil filter pad and oil filter It is available in either 1-1/4" push-on fittings or AN style fittings to plumb the water inlet and exit This cooler uses a large well designed 3" core and is available hard anodized or polished as an option An offshore model is available to clear mid-engine motor mounts This cooler completely disassembles for servicing.


Big Block Chevy Gen 4 Bolt-On Cooler, 5" X 19-3/4" Length
Your Price:
$529.99

Big Block Chevy Gen 4 Bolt-On Cooler, 5" X 19-3/4" Length

260-OC201

Big Block Chevy Gen 4 Bolt-On Cooler, 5" X 19-3/4" Length

This Olsen hi-performance engine oil cooler has a unique feature - it bolts directly to the engine block and requires no additional oil plumbing It merely sandwiches between the oil filter pad and oil filter It is available in either 1-1/4" push-on fittings or AN style fittings to plumb the water inlet and exit This cooler uses a large well designed 3" core and is available hard anodized or polished as an option An offshore model is available to clear mid-engine motor mounts This cooler completely disassembles for servicing.


Big Block Chevy Gen 5 Bolt-On Cooler, 5" X 19-3/4" Length
Your Price:
$529.99

Big Block Chevy Gen 5 Bolt-On Cooler, 5" X 19-3/4" Length

260-OC202

Big Block Chevy Gen 5 Bolt-On Cooler, 5" X 19-3/4" Length

This Olsen hi-performance engine oil cooler has a unique feature - it bolts directly to the engine block and requires no additional oil plumbing It merely sandwiches between the oil filter pad and oil filter It is available in either 1-1/4" push-on fittings or AN style fittings to plumb the water inlet and exit This cooler uses a large well designed 3" core and is available hard anodized or polished as an option An offshore model is available to clear mid-engine motor mounts This cooler completely disassembles for servicing.


Big Block Chevy Gen 5 Offshore Cooler,  5" x 14 3/4" Length
Your Price:
$529.99

Big Block Chevy Gen 5 Offshore Cooler, 5" x 14 3/4" Length

260-OC402

Big Block Chevy Gen 5 Offshore Cooler, 5" x 14 3/4" Length

This Olsen hi-performance engine oil cooler has a unique feature - it bolts directly to the engine block and requires no additional oil plumbing. It merely sandwiches between the oil filter pad and oil filter. It is available in either 1-1/4" push-on fittings or AN style fittings to plumb the water inlet and exit. This cooler uses a large well designed 3" core


Stringer Mount Remote Cooler, 5" X 14-3/4" Length
Your Price:
$529.99

Stringer Mount Remote Cooler, 5" X 14-3/4" Length

260-OC102

Stringer Mount Remote Cooler, 5" X 14-3/4" Length

Available in either 1-1/4" push-on fittings or AN style fittings to plumb the water inlet and exit This cooler uses a large well designed 3" core and is available hard anodized or polished as an option An offshore model is available to clear mid-engine motor mounts This cooler completely disassembles for servicing.