Question on "normal" temp range

[Johley8]

Granted it has been real hot on the Western slope here in Colorado but seeing the Temp guage go right up to the upper white line just befor the "danger Zone":eek: makes me nervous as i do alot of traveling to races and such on the eastern side of the divide so the engine is doing alot of work going over passes.

 

So my question(s) is this, Is this pretty normal? it does back off rather fast when decellerating.

Is there anything i can do to prevent it?

 

I have a 01 outback with a 2.5 with 135K on it, the therm and pump were replaced at the usual 105K

 

Any thoughts would be great!

 

Thanks!

[porcupine73]

Is the coolant level full under the rad cap? One possibility is the cooling system has simply reached its maximum heat rejection capacity and then the temperature starts to climb.

 

Otherwise, it could be anything that would reduce the heat rejection capacity, such as scale/oil/build up in the cooling system, blockages in the radiator, crimped hoses, water pump not pumping enough, etc. Was the water pump oem? Some water pump models Subaru superceded with a 'high flow' version at some point.

[Johley8]

Is the coolant level full under the rad cap? One possibility is the cooling system has simply reached its maximum heat rejection capacity and then the temperature starts to climb.

 

Otherwise, it could be anything that would reduce the heat rejection capacity, such as scale/oil/build up in the cooling system, blockages in the radiator, crimped hoses, water pump not pumping enough, etc. Was the water pump oem? Some water pump models Subaru superceded with a 'high flow' version at some point.

 

Yep it is full and looked "clear" of buildup before it was filled back when they did the Pump and the Pump came fron a dealer up here. So i would hope it is OEM but the dealer up here is pretty bad too so who knows:confused:

[Johley8]

Yep it is full and looked "clear" of buildup before it was filled back when they did the Pump and the Pump came fron a dealer up here. So i would hope it is OEM but the dealer up here is pretty bad too so who knows:confused:

 

there is some blockage from Bugs/stones and there are a set of driving lights on the lower "intakes" onthe bumper.

[porcupine73]

The driving lights might be blocking airflow. The lower intakes direct air kind of in an upward direction to catch the bottom and middle of the radiator. Also climbing hills at relatively slow speed makes the temp climb fairly quickly. How hot is the ambient temp? I climbed some hills today at 3000rpm in 1st gear about 75 deg. F ambient and coolant temp got to about 211 deg. F.

[idosubaru]

that's definitely not normal.

for now, at the very least turn your A/C off before it gets that hot or while climbing. radiator may be partially clogged, they easily get build up in them, i've seen them only a few years old with not many miles on them have lots of white deposits inside. probably wouldn't take much given the heat, pulling hills and running a/c.

 

pull over when it gets above normal and make sure your fans are kicking on as well.

[nipper]

What he ^^^^^ said.

 

nipper

 

Sounds like to me a clogged radiator.

[bulwnkl]

I have a very similar problem in my '05 Baja (turbo). This past week we pulled our boat (~1800 lbs.) far away and went over some mountain passes and other steep grades. At any temps above ~75 degrees, the thing will heat up when pulling a hill. The only solution is to back off and go slower (less boost, less speed) and turn off the A/C. I flushed my cooling system and installed new coolant and Subaru Genuine cooant conditioner (as per the owner's manual) after arriving at our destination to try to alleviate the problem before we came home in hotter weather. No change. The radiator is not blocked nor filled with bugs or anything else. This vehicle has 80,000 miles on it.

 

To the O.P: Do you have an automatic transmission? Does it have a cooler in the radiator? Do you have an oil cooler? Is is a coolant to oil cooler? I have both an engine oil and tranny oil cooler and they are both coolant to oil coolers (factory).

 

I'm wondering: Could the radiator simply be too small? What kind of sense does that make?

[OB99W]

How's the heater? Does turning it on full blast (yeah, I know, not a lot of fun now , but just for a quick diagnosis) help drop the temp?

[nipper]

I'm getting the feeling that either the radiator is to small, or the factory gauge is off, or both.

If you have BOTH an external tranny cooler, and an external engine cooler and are still running hot, my next step would be to install a GOOD aftermarket temp gauge and see what is happening (or use a scangauge).

 

The only way you can remove more heat from the engine is with a large oil cooler, but you need one with a T-stat built into it. Also anything that increases engine oil capacity will help.

 

nipper

[bulwnkl]

For my condition, turning the heat on full blast will slow or stop the temp rise, but will not reverse it.

 

To be clear, the tranny and engine oil coolers I have are the factory ones, which are not separate radiators. The tranny fluid flows into the cooant radiator (ala many GM vehicles), and the engine oil cooler is a place in the filter head where coolant and oil circulate past each other to exchange heat.

 

I can say that at one point, the Autostick feature was disabled by the ECU/PCM/whatever the best name for it is. According to the book, this will happen when the tranny fluid temp is rising too high because computer management of the transmission supposedly will result in lower fluid temps than manual control.

[nipper]

For my condition, turning the heat on full blast will slow or stop the temp rise, but will not reverse it.

 

To be clear, the tranny and engine oil coolers I have are the factory ones, which are not separate radiators. The tranny fluid flows into the cooant radiator (ala many GM vehicles), and the engine oil cooler is a place in the filter head where coolant and oil circulate past each other to exchange heat.

 

I can say that at one point, the Autostick feature was disabled by the ECU/PCM/whatever the best name for it is. According to the book, this will happen when the tranny fluid temp is rising too high because computer management of the transmission supposedly will result in lower fluid temps than manual control.

 

Sounds like they made an engineering cost decision. They went with a smaller radiator for the 5% of people who will never see these conditions.

 

I would get an external tranny cooler (Blu has one) and an external oil cooler. ALso a tranny temp gauge if you do regular towing.

 

nipper

[bulwnkl]

Sounds like they made an engineering cost decision. They went with a smaller radiator for the 5% of people who will never see these conditions.

 

I would get an external tranny cooler (Blu has one) and an external oil cooler. ALso a tranny temp gauge if you do regular towing.

 

nipper

 

It kinda sounded like that to me, too.

 

Blu? Board member or company?

 

I'm thinking that if I put a tranny cooler in, it'll be inline with and upstream of the OEM radiator cooler in order that when I'm driving to work at 25 below zero in the winter not towing I don't freeze the fluid solid.

[nipper]

It kinda sounded like that to me, too.

 

Blu? Board member or company?

 

I'm thinking that if I put a tranny cooler in, it'll be inline with and upstream of the OEM radiator cooler in order that when I'm driving to work at 25 below zero in the winter not towing I don't freeze the fluid solid.

 

Blu (see picture of pretty Blue subaru).

 

I have a gauge on mine. I put mine after the radiator. It's interesting watching the gauge. Takes a long time for the tranny to warm up. As long as the gauge is never higher then the engine temp or 100 degrees oover ambient all is well.

What sucks is my factory JDM gauge is in C and my brain is in F. Hottest its gotten so far is 90 C.

 

nipper

[Johley8]

I have a very similar problem in my '05 Baja (turbo). This past week we pulled our boat (~1800 lbs.) far away and went over some mountain passes and other steep grades. At any temps above ~75 degrees, the thing will heat up when pulling a hill. The only solution is to back off and go slower (less boost, less speed) and turn off the A/C. I flushed my cooling system and installed new coolant and Subaru Genuine cooant conditioner (as per the owner's manual) after arriving at our destination to try to alleviate the problem before we came home in hotter weather. No change. The radiator is not blocked nor filled with bugs or anything else. This vehicle has 80,000 miles on it.

 

To the O.P: Do you have an automatic transmission? Does it have a cooler in the radiator? Do you have an oil cooler? Is is a coolant to oil cooler? I have both an engine oil and tranny oil cooler and they are both coolant to oil coolers (factory).

 

I'm wondering: Could the radiator simply be too small? What kind of sense does that make?

 

It does have the AT cooler and the ac is in front of the radiator and the at cooler behind. I have an apptment with the local GOOD mechanic on thur to have a look at it. Temps her have been 90+ like toaday it is 96 and i just ran home from work and it was fine with the A/C on and such at highway speeds, granted the drive is only 15min.

[Johley8]

How's the heater? Does turning it on full blast (yeah, I know, not a lot of fun now , but just for a quick diagnosis) help drop the temp?

 

Yep did that too:Flame: and that is how it felt, DAM HOT! and did not really drop the temp.

[frag]

I think that before doing anything costly you should check the thermostat to see if it's OEM or aftermarket. I and other members have had problems with aftermarket therms. The one I had bought had a smaller opening, opened later and stayed open for a shorter time than OEM. I posted the comparison a long time ago. The fact that your rad has damaged or blocked sections due to bugs and stones does'nt help either. But I think a good stat would cure the problem. After 12 years, my rad is in the same condition than yours and I have had no episode of overheating ever and I have to climb long hills in hot conditions when I go to the cottage.

Good luck!

[Johley8]

So the final outcome was tha that rad was very clogged bolth in and out, the bottom 1/4 was so clogged that you could not see thlrough it at all:mad:

so the new one is in and all problems solved. My mech also said it is pretty common to see this since the rad is sandwhiched beween the ac and hte at coolers.

[Setright]

Added to which they put the top (flow in) rad hose on the middle of the radiator. I've seen these clog INTERNALLY in less than 50K miles. No flow at the ends and the gunk starts to build up

[Petersubaru]

Added to which they put the top (flow in) rad hose on the middle of the radiator. I've seen these clog INTERNALLY in less than 50K miles. No flow at the ends and the gunk starts to build up

Just curious here..but what would make the radiator clog up so quickly, if hopefully, the owner was keeping up with the coolant maintenance

[nipper]

Just curious here..but what would make the radiator clog up so quickly, if hopefully, the owner was keeping up with the coolant maintenance

 

This is why you change the fluid every 3 years. It is unusual for a radiator to clog this early. The wrong antifreeze, tap water, contaminates in the antifreeeze all posabilities.

 

And sometimes people are unlucky.

 

Which reminds me, the original poster needs to check his transmission fluid. A leaking cooler and make the antifreeze clump and clog up. With the new radiator the point is moot as far as internal leaks.

 

nipper

[Setright]

The flow is too slow at the "edges" of the central piped radiators. So, any little contaminate will tend to drop off there and stick there. That will attract the next contaminate...chain reaction. By 50 k miles, only the central 4-6 inches of the rad flow coolant. Common fault.

 

I do suppose yearly flushing (just with pure water) and coolant replacement will keep this clogging at bay. Three years is too long for this design.

[Johley8]

This is why you change the fluid every 3 years. It is unusual for a radiator to clog this early. The wrong antifreeze, tap water, contaminates in the antifreeeze all posabilities.

 

And sometimes people are unlucky.

 

Which reminds me, the original poster needs to check his transmission fluid. A leaking cooler and make the antifreeze clump and clog up. With the new radiator the point is moot as far as internal leaks.

 

nipper

Yep have ben changing it out every 2. The main source/location was in the baffles themselves and not what i would call magor cloging inside. I used to do alot of dirty, dusty driving and the build up in the a/c then radiator just clogged up. Bummer!