Getting warmer than expected

corsa79

corsa79

Forum Member
Joined
Oct 18, 2009
Messages
74
Location
Yeronga
Car Year
2005
Car Model
Forester xt my06
Transmission
Manual
Hi all had a look through the forums and cant see anything that related. I recently found I had a slight weep from my bottom radiator tank on my 2006 xt forrester. I live in Julia Creek where it is often over 40deg c in summer. I have put in a full aluminium radiator with 42 mm core upgraded my thermostate to a high flow one and replaced top and bottom hoses. Also fitted a new radiator cap. I am not loosing coolant eather. I would of thought after doing this on these hotter days it would just stay in its normal position of just under half temp but after say 20min driving it gets up to second line on temp gauge. It drops back down reasonably quickly when I come back into town to normal. I also have rally 4000 spot lights on my bull bar. Does everyone think it may be a airflow problem with spotties and fans being closer to engine with thicker core. Or do you think the water pump is getting sluggish. Or do I have another issue.
 
What brand coolant and how diluted is it? I had a sinilar problem in my Gt Foz... changed what you hadminus the radiator and it was sorted.
are both your fans coming on at 95 degrees?
The standard gauge is very inaccurate and often you could be over heating and not even know.
 
It could be any number of issues.

Has it been run with good quality and correctly mixed coolant previously? If not the impellers on the water pump could be corroded away and/or scale deposits in the cooling system.

Did you retain the fan shroud with the thicker core radiator?

Are you using good quality oil and is it changed regularly.? Oil assits in cooling the engine too.

Like taza said, standard temp guages are woefully inaccurate. If you still have concerns fit an afermarket guage or better yet an oil temp guage.
 
Thanks its always had good quality coolant Castrol stuff. mixed 50 50 mind you did have issue with cap not sucking it back and replaced it and could be under now after topping up. also use deminerilized water everything looked clean and corrosion free.
still has shroud and fans operate at wright temp. Have got obd says it gets to max off 103 104
 
Unsure on what you mean by upgraded thermostat to a high flow one. What temp does this new thermo open at?? If it opens at a higher temp compared to stock, then you have gone backwards. If it opens at a lower temp and in my experience usually 10 degrees less with quality aftermarket thermostats and everything checks out, i'll bet its an airflow issue.

Reading a few sg xt builds with bullbars and spotties, owners usually record higher engine temps so they modify there bullbars to let more airflow through.

I think a members journal "dellsfoz" had to do this so check it out for reference

Goodluck
 
I should add that I have a sg xt with subiextreme bulbar and a 20" lightbar for night driving. I went with the lightbar so that it would not drastically interfere with radiator airflow. My before and after temps after install are exactly the same.

One check you could do is take off the spotties and see if it makes a difference.
 
corsa79 said:
Thanks its always had good quality coolant Castrol stuff. mixed 50 50 mind you did have issue with cap not sucking it back and replaced it and could be under now after topping up. also use deminerilized water everything looked clean and corrosion free.
still has shroud and fans operate at wright temp. Have got obd says it gets to max off 103 104
Click to expand...

And would that be on a 40 degree day?
 
Gidday C79

Modern cars have an airflow efficiency that's pretty unreal.

The very best have a coefficient of drag around 0.29. Even the dear old SG Forester is around 0.33.

What this translates to in the real world is that getting any airflow into the radiator is quite a feat of engineering. Chances are that your spotties have interfered with that.

On my first Mitsubishi Colt (coeff. of drag ~0.29 ... ), just folding the external mirrors flat decreased the fuel consumption by about 2 mpg when sitting on around 140 kmh ...
 
105 is the max normal temp for a ej style engine. Boxer enginea do run quite warm... anywhere upto 100 degrees is fine on a moderate day. 105 max with a load on a hot day. Any hotter and you have major problems.
 
Doubt that it would be the spotlights impeding air flow. I have IPF 900 xs mounted on the bull bar and makes no difference . As Catchya has suggested you can remove the lights and test.
Sound more like a thermostat issue. Either it is designed to open at a higher temp or it could be sticking. Can you put the old one back in ?
 
I have 3 driving lights mounted in front on a full sized SubaXtreme bull bar.
Only overheating prob was when the top tank failed and what drew my attention was the erratic fluctuations of the temp gauge.
The car has been in hot conditions many times. When new it spent time in north QLD and the NT with outside indicated temps of 40+ deg C with three persons and luggage. Also across the Simpson twice.
IMHO overheating is not normal.
 
I have found with my XT that movement is good for cooling. It always indicates the same place on the temp gauge, even when once being caught in a traffic jam on the Toowoomba Range in the middle of summer & smoke started coming out the air scoop. It sounds like the thermostat is behaving differently
 
When you say you've been using demineralised water, do you mean to top up? What coolant?

You might be best getting a new genuine thermostat.
 
Thanks everyone. I used Castrol concentrate as the closest Subaru dealer is 600km away and mixed coolant 50 50 with demineralised water to mix it and to top up. The thermostat is a gates one and opens cooler and also classed as high flow. At an idle it gets to temp just above 80 and holds around town it gets to just over 90 and holds just getting up to 100 sitting on 110kmh on 42 to 45 deg c days with near no humidity. As said no leaks no coolant usage slight oil usage over between service runs well and actually been getting better fuel economy since all the changes. Also climate control is on 25 and is working. Might try some things and let you all know as I have already checked all the things you have suggested except for taking the spotties off. Thanks everyone.
 
Well took off the spotties today they where rally 4000 and didn't get over 100 a definite improvement. So it looks like its airflow problem. Im going to look at getting smaller spotties try to make some more venting and I think ill modify my fans and shroud to give some more room that side to with the thicker radiator.

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That's a good result, C79. At least so far as finding the probable cause.

Oil viscosity is measured using 100C block temperature as the reference point. If your block exceeds this, the viscosity of your oil falls off accordingly - a BAD thing ... :(.
 
Ratbag said:
Oil viscosity is measured using 100C block temperature as the reference point. If your block exceeds this, the viscosity of your oil falls off accordingly - a BAD thing ... :(.
Click to expand...

I dont think the oil gets thinner. Engine oils are funny things, they're thinner at the cold end and thicker at the hot end. The issue is the oil breaking down when it gets too hot.

Corsa, you could try a lightbar. Theyre getting pretty cheap now for decent ones & theyre much slimmer. Depending on your laws you can even mount it on top of your bullbar.
 
NachaLuva said:
I dont think the oil gets thinner. Engine oils are funny things, they're thinner at the cold end and thicker at the hot end. The issue is the oil breaking down when it gets too hot.
Click to expand...

And viscosity measurements are even funnier. Why I quote 100°C block temperature is because that is the standard for the hot end viscosity measurement. There is a lot more to it than being "thinner at the cold end and thicker at the hot end". Check out all the various articles about this on Wikipedia for a once over lightly of how it all works. Quite fascinating really.

However, when all is said and done, a block temperature of 100°C is the end of the line for relying on one's oil to properly lubricate the engine. It's why I would never use the recommended 0W-20 FS in either of our Foresters - both EJ-253 engines. I only ever use 5W-40 FS in them. There is a slightly greater "margin for error" than with 5W-30 FS when the ambient temperature is 40°C+ ... and no difference at the low end of the scale unless one is in the Arctic or Antarctic ...

Corsa, you could try a lightbar. Theyre getting pretty cheap now for decent ones & theyre much slimmer. Depending on your laws you can even mount it on top of your bullbar.
Click to expand...

Agree about the lightbar.
 
Corsa I would not modify anything to do with your fans/shroud. They look to fit perfectly on your radiator despite the rad being aftermarket. If it did not fit nice and neat and the fan shroud was broken not giving a proper seal then yes, replace/modify.

Is the fan and fan shroud still genuine factory items or have they been replaced with non genuine?

I'm not sure if all foresters came with underside engine plastics that cover from the radiator back to the clutch end of the motor so to speak as mine when I bought it did not. If they do and yours is not on, this will also be a contributing factor as it helps direct air through and help stop the path of least resistance.

I simply bought a bash plate to cover this problem.

Goodluck
 
Maybe get an auto sparky to do a current test on the fan motors.
See if they are actually working to design and pulling enough air.
I keep thinking of mine with three lights and no cooling probs.
 
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