why does my subaru overheat without a thermostat

Asked by Oct 26, 2013 at 06:01 PM about the 1996 Subaru Legacy 4 Dr Outback AWD Wagon

Question type: Maintenance & Repair

bought it a week ago  ...prev owner had some overheat trouble...it seems that it does it for a bit then has no prob then does it again

3 Answers

3,795

your car overheats without a thermostat because the water is continuously circulating. when a working thermostat closes, it allows the water to stay in the radiator long enough to cool down. when the temperature in the engine gets hot, the thermostat opens and allows the cooler water in the radiator into the motor and the warmer water from the engine goes into the radiator to be cooled.

75

That's not how thermostats work. Too much water flow only slows down proper warmup. The water doesn't need to sit in the radiator to cool sufficiently unless there is something wrong with the radiator. Your issue is likely somewhere in the radiator. Are the fans working properly? Is there a blockage, like leaves our other debris, preventing proper airflow through the radiator fins? If all of that is ok then your problem is either in the radiator, something preventing sufficient water flow to cool off the engine, or elsewhere in the cooling system causing the same issue. If nothing is reducing the airflow then get the cooling system flushed and replace that thermostat with a correctly rated one.

3,005

It's likely that the overheating is due to a blown head gasket.

4 out of 4 people think this is helpful.

Your Answer

Add photo

Related Questions

Legacy

Looking for a Used Legacy in your area?

CarGurus has 16,651 nationwide Legacy listings starting at $800.

ZIP:

Search Subaru Legacy Questions

Subaru Legacy Experts

#1 Anthony_60
Anthony_60
Reputation 1,200
#2 Nick Eidemiller
Nick Eidemiller
Reputation 690
#3 dandyoun
dandyoun
Reputation 630
View All

Related Models For Sale

Used Subaru Impreza
177 Great Deals out of 15,339 listings starting at $1,995
Used Honda Accord
717 Great Deals out of 83,073 listings starting at $500
Used Toyota Camry
871 Great Deals out of 92,521 listings starting at $1,300
Used Honda Civic
511 Great Deals out of 81,687 listings starting at $558
Used Nissan Altima
836 Great Deals out of 78,333 listings starting at $470
Used BMW 3 Series
1,044 Great Deals out of 35,400 listings starting at $900
Used Audi A4
201 Great Deals out of 11,075 listings starting at $1,333
Used Honda CR-V
692 Great Deals out of 57,485 listings starting at $1,600

Used Cars For Sale

2017 Subaru Legacy For Sale
11,084 listings starting at $19,665
2016 Subaru Legacy For Sale
52 Great Deals out of 868 listings starting at $12,795
2015 Subaru Legacy For Sale
37 Great Deals out of 844 listings starting at $11,500
2014 Subaru Legacy For Sale
42 Great Deals out of 1,176 listings starting at $9,499