|APPLICABILITY:||1999MY and later Impreza & Forester|
|2000MY and later Legacy & Outback|
|2006MY and later Tribeca|
If you encounter a vehicle which experiences coolant coming out of the coolant reservoir tank, it may be caused by the radiator cap pressure valve being stuck open by debris sucked up through the reservoir tank hose. As the cooling system cools down, it sucks coolant back into the radiator. If there is debris that settles to the bottom of the reservoir tank, the hose is low enough to also suck them back into radiator. This causes the radiator cap not to seal, allowing excessive amount of coolant to escape overflowing the reservoir tank. If this condition continues over time, there will not be enough coolant in the system to maintain proper engine temperature.
In order to correct the condition you need to clean (and test) or replace the radiator cap, clean out the reservoir tank, and shorten the hose slightly, following the repair procedure.
PRODUCTION LINE CHANGE
The shorter coolant reservoir tank hose was used in production as follows:
|Impreza Sedan||8*525006||March 2008|
|Impreza Wagon||8*830415||March 2008|
|Legacy||Scheduled for August 2008|
|Outback||Scheduled for August 2008|
- Radiator Cap Cleaning
Many caps can be successfully cleaned. The important part is the thorough cleaning of the negative pressure valve. If this is not done completely, remaining debris may result in a repeat issue. If there is an excessive amount of debris or the sealing rubber on the cap appears to be pitted or damaged, replace the cap. Note: If replacing the cap, skip to Step 2.
Using clean water and a brush, thoroughly clean the cap seal surface. Note: A used toothbrush which has been cleaned works great.
Manually open the negative pressure valve. Using clean water and a brush, thoroughly clean the valve (inner and outer surface) and the valve seal surface.
Check the radiator cap valve opening pressure using a radiator cap tester to insure the cap is within specification (refer to the applicable Subaru Service Manual). Note: If the cap is out of specification replace it.
- Coolant Reservoir Tank Cleaning
Using clean water, thoroughly clean the inside of the reservoir tank.
Reinstall reservoir tank. Fill with coolant to the Full mark. Note: Be sure to use genuine Subaru Super Coolant or Subaru Long Life Coolant, depending upon what type of coolant is currently in the system.
- Coolant Reservoir Tank Hose Modification
Remove the hose from the reservoir tank. Cut 20mm from the bottom of the hose at a 45º angle. Reinstall hose in reservoir tank.
Start engine and permit to fully warm up.
Turn off engine and allow to fully cool down.
Recheck coolant level in reservoir and add coolant if needed. Note: Be sure to use genuine Subaru Super Coolant or Subaru Long Life Coolant, depending upon what type of coolant is currently in the system.
For vehicles within the Basic New Car Limited Warranty period, this repair can be claimed using:
|Radiator Reserve Tank Hose Modification (Includes cap cleaning and testing)||A 228-188||CCM-48||0.4|
|Radiator Reserve Tank Hose|
Modification and Cap Replacement