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97 EJ25D Coolant gauge stuck?

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Since I got my 97 Legacy Outback in november, the coolant gauge has never gotten above roughly 1/3 of the way up. Now that Im finally getting some nicer, warmer whether im worried about an innacurate gauge. A few times now Ive looked under the hood and seen some coolant on top of the resivoir and splashed down the front of the timing belt cover. Could this be a simple overflow? Hose is tight to the resivoir. Is there any way I can tell if I have a faulty sonsor/gauge? Or is it normal for the gauge to read 1/3 all the time after warming up? I dont take very long trips, average runs for about an hour at a time but no road trips or anything. (Dont take it on the highway often due to a cam seal leak that drips/blows onto the headers and front cat, smokes a bit) just wondering if other owners have the same reading.

 

On a side note, how are UEL headers in comparison to stock? Currently have a small exhaust manifold leak and considering replacing them with the cheap knockoff UEL headers that are pretty much the same pricewise as knockoff EL headers.

 

Thanks for the advice!

Not normal. It should be just a below half. Likely someone drilled holes in the thermostat or took the thermostat out entirely to stave off overheating and cover up bad head gaskets.

 

Look for bubbles in the overflow tank while the engine is running.

Another tell-tale sign is to check for pressure in the cooling system after only about 10-15 seconds of running.

Before the first start of the day open the hood and open the radiator cap. Put the cap back on and squeeze the upper radiator hose.

Now start the engine, after about 15-20 seconds of running squeeze the upper hose again. If there is pressure in the upper hose, thats a bad head gasket.

Mine sits a little over 1/3 but well below 1/2. 

 

You have an EJ25D, correct? If so they're prone to head gaskets failing and leaking exhaust into the coolant. This pushes the coolant out, which is likely what you saw. New head gaskets should be a permanent fix, I used Fel Pro late last year and they're holding up (but don't have many miles on it... lots of abuse though). I think the new OEM gaskets are good too, and have heard good things about Six Stars. 

+1 on problem being bad head gaskets. I too, suspect that the thermostat has been removed to mask over the problem of over heating due to bad head gaskets.

I suspect the thermostat is still there. If it wasn't, the temp would move around more.

If the car is new to you, you should confirm that the thermostat is a working OEM-style unit.

 

Thermostats%204%20sm.jpg

 

 

Take yours. make sure it's closed, put it in hot water on the stove, monitor the temps with a thermometer, confirm it opens before 180 degsF or so.

 

OR, if you are gonna install a new one, test it too before you install it.

Edited by 1 Lucky Texan

  • Author

Well it was previously owned by the "little old lady." It has just ticked over to 77,000 yesterday. Don't think any things beig covered up or hidden. Yes it's an EJ25D, I've been worried about head gaskets for a while. It could be the thermostat, not sure.

 

Also, are both cooling fans supposed to be running at the same time? The left one is the only one that runs. I know they have problems with the connectors being too exposed on the bottom, haven't gotten time to check and see if any connections are good. I'll to the head gasket test when I have a chance. Thanks for the advice everyone!

(Knew I shoulda got the 2.2... Lol)

the logic on which fans turn and/or how fast if they are 2-speed, is complex but I THINK if the car is warmed up AND the a/c is on - both should be running.

 

someone else might have a better answer.

  • Author

No bubbles in the coolant resivoir with engine running, ill do the hose test tomorrow morning.

Still nothing from the right fan, even with a (very) warm engine and the AC on.

Would a faulty thermostat cause an innacurate reading on the gauge? Seems a lot warmer than what it shows. Does anyone know what the temp would be normally? I find the fact that the gauge is unlabled annoying.

  • Author

Should have also mentioned earlier that when the engine is cold, it has a strange idle. It will idle fine, sound like its stalling then quickly rev to about 1000 rpm, then steady out. Happens about once or twice a minute until it warms up.

Thermostat?

The fans have 2 relays per fan (low and high speed), and independent fuses. All in the underhood fuse panel.

 

To test operation put the ECM in test mode. Plug in the green plugs under the drivers dash and turn the key ON. That will cycle both fans in low and high speed.

  • Author

These? Saw them a while ago. Wondering what they were for...

The fans have 2 relays per fan (low and high speed), and independent fuses. All in the underhood fuse panel.

To test operation put the ECM in test mode. Plug in the green plugs under the drivers dash and turn the key ON. That will cycle both fans in low and high speed.

post-51430-0-05764600-1400114937_thumb.jpg

  • Author

Not normal. It should be just a below half. Likely someone drilled holes in the thermostat or took the thermostat out entirely to stave off overheating and cover up bad head gaskets.

Look for bubbles in the overflow tank while the engine is running.

Another tell-tale sign is to check for pressure in the cooling system after only about 10-15 seconds of running.

Before the first start of the day open the hood and open the radiator cap. Put the cap back on and squeeze the upper radiator hose.

Now start the engine, after about 15-20 seconds of running squeeze the upper hose again. If there is pressure in the upper hose, thats a bad head gasket.

Did the upper rad hose check this morning. No pressure in the hose after a short while running.
  • Author

This was after a half hour drive. Bubbles popped up one by one, but quickly stopped altogether in less than a minute. Could it just be from driving vibrations or head gasket?

This was after a half hour drive. Bubbles popped up one by one, but quickly stopped altogether in less than a minute. Could it just be from driving vibrations or head gasket?

post-51430-0-32031400-1400182502_thumb.jpg

Edited by pginter96

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