I have a 2000 Legacy Outback (EJ252), 5 speed. (130,000 miles)

It seems to be running great at all times, but when I go on steeper uphill, the engine temperature gauge climbs up.

This makes nervous even though it has not been out of the safe zone yet. I believe it should be rock solid (as my old '96 Legacy EJ22 was) as this last time it went even higher than before, almost 3/4 of the way.

When I drive it on level ground, or interstate with smaller hills it seems fine.

But when I go skiing and have to climb up to the parking lot at a higher elevation, the temperature seems to climb too. It did not a few weeks ago when I went skiing, but this last time it did. Just don't know what the inconsistency is.

The following I have checked:

 

-Coolant fluid level is good, recently changed, and no leaks visible anywhere.

- According to my manual (Chilton) if the radiator hose is hot the thermostat is working so I think that should be ok!?

-Engine warms up to operating temperature in normal amount of time.

-Cooling fan comes on when stopping (at red light etc.)

All other fluid levels are fine.

 

Does anyone know why the dashboard temperature gauge is not rock solid?

Why the inconsistency?

 

I know some of the 2.5 engines have head gasket problems, especially the EJ25D (96-99) but I heard this series (EJ252/251) does not overheat, but only leaks coolant externally on the back of the engine, easy to spot.

Is my engine really heating up, or the gauge is lying to me?

 

Any ideas?

Lets do the sinple things BEFORE somone screams HG. Temp gauge is working fine (why do people blame the gauges?)

 

Replace the thermostat with one from subaru and the radiator cap. Never doubt the temp gauge as it can get you in expensive trouble weather it is right or wrong. It sounds like your T stat is only opening 1/2 way.

 

 

nipper

Yes - replace the thermostat with an OEM one from the dealer. I've seen cheap thermostat's not be able to hold steady temp like that.

 

Thermostat is a $25, 15 minute change out - that's the first place to start for sure with your problem.

 

GD

- According to my manual (Chilton) if the radiator hose is hot the thermostat is working so I think that should be ok!?

 

 

 

Thermostat is in the bottom o the engine at the waterpump inlet. You need to check the lower radiator hose. If it is cool or only slightly warm, then you have a flow issue with the Tstat.

Just replace it not something to cheap out on unless you like the idea of chainging headgaskets.

 

 

nipper

Don't forget to BURP the system to remove all air after you work on the sytem.

 

Thanks for all the tips. Exactly what I suspected.

Hopefully this is the problem as it is an easy fix.

Thanks a lot.

I replaced the thermostat with a new OEM (Made in Japan) part ($15), as well as the radiator cap ($8 made in japan). Took the car on a 500+ mile trip and my temperature gauge is rock solid again.

 

The thermostat I pulled out was 1/2 inch shorter than the new OEM one, and quite a bit smaller in the core copper part. Made in USA - looking like a cheap aftermarket band-aid someone used before me.

 

Everybody who says to use OEM Subaru parts, is RIGHT!

Glad to hear that it solved your problem!

glad i ran across this thread i was seeing the same thing with my 2.2 and long steep uphill interstate runs, i guess i need to switch to an oem t-stat on my hybrid motor when i put it together

Good to hear man.

Mine only goes up about 1/4 of the way above the normal position and it does it randomly regardless of OAT or load. But it usually never moves. The cooling fan relay went out and I replaced that. The T-stat is 1 year old and about 6000 miles and was OEM as was rad cap. Is this a burping symptom? (98 Forester 2.5 DOHC)

Edited May 9, 201213 yr by Luvn737s

Have you checked the coolant level? It could just be low. The DOHC 2.5 is famous though. Look for bubbles in the coolant with the engine running.