Tag Archives: Coolant

Coolant is critical to your Subaru

Coolant is Critical to your Subaru:

The heart of any vehicle is the engine. It’s what makes it go. Anything that jeopardizes the operation of the engine can have disastrous effects and result in extensive repairs. If the engine is the heart of the vehicle, then surely the cooling system is the “circulatory system” that keeps the engine operating at optimum temperatures. If it doesn’t, bad things are going to happen.

Subaru engines are modern masterpieces of technology and precision. Manufactured of multi-alloy metals and exotic materials, these engines contain more components, weigh less, produce more power and torque and are more durable than the old iron engines of 40 years ago. However, even these high-tech engines can be damaged or destroyed by excessively high internal temperatures.

Though more energy efficient than ever before, the combustion of fuel and air in the cylinders that produces the power that propels the vehicle still creates an enormous amount of waste heat. This is carried away from the cylinders either by venting it out through the exhaust system or via the cooling system. If either of these systems fail to keep the engine at normal operating temperatures, an overheating condition occurs. Of the two, the cooling system is most vulnerable.

Coolant is Critical to your Subaru: Always use Subaru oem coolant in your Subaru car.

The cooling system can easily be contaminated or compromised by anyone putting the wrong products into the radiator or reservoir. Often, Subaru owners or service facilities that are not aware of the specific needs of the vehicle will put incorrect chemicals into the system. In fact, according to figures published by the U. S. Department of Transportation, coolant-related problems are the primary cause of mechanical breakdowns on the highway. Many of these breakdowns could have been avoided by the use of proper coolant and the right additives.

Cool Down WRX Turbo Procedure

Cool Down WRX Turbo Procedure:

It is not necessary to perform a cool down/idling procedure on Subaru WRX turbo models, as was recommended with past turbo models. “The current 2.0 liter turbo engine has a far greater cooling capacity and, coupled with technology advances, makes this practice no longer necessary. This explains why information about a cool down is not included in the Impreza Owner’s Manual.

Cool Down WRX Turbo Procedure: It is not necessary to perform a “cool down/idling” procedure on Subaru WRX turbo models, as was recommended with past turbo models.

The heat contained in the turbocharger begins to vaporize the coolant at the turbocharger after the engine is stopped. This hot vapor then enters the coolant reservoir tank, which is the highest point of the coolant system.

At the same time the vapor exits the turbocharger, coolant supplied from the right bank cylinder head flows into the turbo. This action reduces the turbocharger temperature. This process will continue until the vaporizing action in the turbocharger has stopped or cooled down.

Timing Belt and Water Pump Replacement Subaru WRX/STi

Timing Belt and Water Pump Replacement Subaru WRX/STi:

Timing Belt and Water Pump Replacement is critical in keeping your Subaru WRX/STi in good condition and to prevent the valves from hitting your engine’s pistons.

Tools used:

3/8 Ratchet
1/2 Ratchet
10, 12, 14, 22mm sockets
short extension
Impact wrench or strap wrench (I used both on separate occasions.)
Torque Wrench
Small metal ruler to measure belt deflection.
Drain pan and funnel for the coolant.
Brake Kleen
Lots of paper towels/shop rags.
3/8 socket driver (very handy.)
Feeler gauges
2mm allen wrench
allen socket for the right camshaft (6mm maybe?)
C-Clamp

Timing belt kit and misc:


Gates TCK328RB Timing Belt Component Kit

Gates 42030 Water Pump

Gates 34012 Thermostat


NYPPD Billet Timing Belt Guide Subaru Impreza WRX EJ20 STi EJ25 2002-2013 Turbo

Genuine Subaru SOA868V9270 Super Coolant

Subaru SOA635071 OEM Coolant System Conditioner

Helpful tools:

Subaru Camlock Tool for Subaru 2.0L and 2.5L DOHC turbo engines C23-506

Subaru Crank Pulley Tool C23-503

Subaru STD Int/Exh Cam Sprocket Tool – similar to 499207400-A

Subaru Cam Sprocket Tool – AVCS Int C23-501

Go to the next page to get started.

Coolant use and Cooling System for Subaru WRX/STi

What type of coolant should I run in my car? You can never go wrong by using Genuine Subaru Coolant available through your local dealer.

Subaru Genuine Coolant. To the left Super Coolant and to the right long life coolant.

Is the Subaru coolant pre-mixed or not? They have both kinds, but BE SURE to read the labels carefully as they are nearly identical in appearance except the wording on the package!

Is there a required coolant additive? Yes. Subaru Cooling System Conditioner has recently been required to be added with every coolant replacement to prevent coolant system leaks. This recommendation applies to every Subaru model for every model year.

Subaru Cooling System Conditioner has recently been required to be added with every coolant replacement to prevent coolant system leaks. This recommendation applies to every Subaru model for every model year.