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junk
07-01-2015, 10:22 PM
I own 2 subaru outbacks. A 2003 and a 2004. Both have the 2.5 liter engine. Recently my wifes car (2004) has ran hot and pegged the temp gage, but doesn't give the traditional overheat symptoms such as steaming or gurgling the overflow. It doesn't do this often and drives fine 95% of the time. So I've become paranoid about it and check the coolant level often. Every time I pull the radiator cap I either hear it releasing pressure or a vacuum and it's slightly low. Now on my car when you pull the cap it's plumb full of coolant and doesn't make any noise. I plugged in my code scanner and checked the temp and it is getting hot.

I believe the cooling system is in fairly good shape. As in new cap, water pump, thermostat, good hoses, etc. Both cooling fans work. Overflow hose seems good and open. I sprayed the cooling stack out with the power washer making sure not to fold over any fins.

I ordered a cooling system pressure kit to test for a coolant leak and a hydrocarbon kit to check for a bad head gasket. I'm leaning towards a small leak that over times fills the system with enough air to cause an issue.

As long as it keeps running OK we'll keep running it. We've owned the car since 2004 and 6700 miles.

Any thoughts?

-Jeremy

Bob K
07-02-2015, 01:09 AM
Plugged catalytic converter. That's my guess. Maybe there is loose vermiculite in the front of a cat that plugs it at times and then falls away and lets exhaust flow at other times. The vermiculite is the media that holds the ceramic section of the cat in place so the exhaust passes through. As the ceramic media wears away the vermiculite gets exposed and is trapped in the front of the cat.

Bob K

Henry
07-02-2015, 08:51 AM
I own 2 subaru outbacks. A 2003 and a 2004. Both have the 2.5 liter engine. Recently my wifes car (2004) has ran hot and pegged the temp gage, but doesn't give the traditional overheat symptoms such as steaming or gurgling the overflow. It doesn't do this often and drives fine 95% of the time. So I've become paranoid about it and check the coolant level often. Every time I pull the radiator cap I either hear it releasing pressure or a vacuum and it's slightly low. Now on my car when you pull the cap it's plumb full of coolant and doesn't make any noise. I plugged in my code scanner and checked the temp and it is getting hot.

I believe the cooling system is in fairly good shape. As in new cap, water pump, thermostat, good hoses, etc. Both cooling fans work. Overflow hose seems good and open. I sprayed the cooling stack out with the power washer making sure not to fold over any fins.

I ordered a cooling system pressure kit to test for a coolant leak and a hydrocarbon kit to check for a bad head gasket. I'm leaning towards a small leak that over times fills the system with enough air to cause an issue.

As long as it keeps running OK we'll keep running it. We've owned the car since 2004 and 6700 miles.

Any thoughts?

-Jeremy

If it was one of 3 GM engines, I would guess an intake gasket(s). Anyway, any signs of coolant on the oil dip stick?

Henry

Phil V
07-02-2015, 09:05 AM
I agree, it sounds like a head gasket. Either do or have done a cylinder leak down test. That will tell you if it has a bad head gasket.

If you ever overheat an engine for any reason (even if it's the not the head gasket) then a warped head/bad head gasket soon will be part of the problem. In most cases it's a waste of time to put a new/used head or have the old head resurfaced because the lower end will go out in a relatively short time. That head that warped the head is the same heat that cooks the bottom end. I've seen it several times where when the head/head gasket are replaced the engine runs fine for a short while then all of a sudden the the mains and rod bearings go out.

junk
07-02-2015, 11:43 AM
Thanks for he suggestions.

Catalytic convertors were replaced around 145,000. Car has 199,000 now. I hadn't thought of them, but won't rule them out. This car has california emissions and is very sensitive to the cats. I have aftermarket cats on it now.

I've not noticed oil and coolant mixing, but need to check the oil again. Coolant is always green, but the overflow bottle does have some "dirt" crap on the inside of it. Reminds me of a car with a head gasket leak, but coolant isn't "dirty".

I did the head gaskets around 100,000 as this generation of subaru is known for externally seeping head gaskets. And we had an external coolant leak. I have some subaru coolant conditioner on order to put in. I think it's basically a stop leak. Normally I'm not for miracle in a bottle, but I really only want another 20-30K or so out of this. So if it buys some time I'm cool.

If it does need big head gaskets or heads I'm not sure what I'll do. I'm not real interested in rebuilding the engine. Cars got a dirty title with previous wreck. Might look for similar generation wrecked car with lower miles and cannibalize this one.

All my stuff I ordered should be here today so i'll play around with it tonight.

Thanks
Jeremy

Henry
07-04-2015, 09:46 AM
Thanks for he suggestions.

Catalytic convertors were replaced around 145,000. Car has 199,000 now. I hadn't thought of them, but won't rule them out. This car has california emissions and is very sensitive to the cats. I have aftermarket cats on it now.

I've not noticed oil and coolant mixing, but need to check the oil again. Coolant is always green, but the overflow bottle does have some "dirt" crap on the inside of it. Reminds me of a car with a head gasket leak, but coolant isn't "dirty".

I did the head gaskets around 100,000 as this generation of subaru is known for externally seeping head gaskets. And we had an external coolant leak. I have some subaru coolant conditioner on order to put in. I think it's basically a stop leak. Normally I'm not for miracle in a bottle, but I really only want another 20-30K or so out of this. So if it buys some time I'm cool.

If it does need big head gaskets or heads I'm not sure what I'll do. I'm not real interested in rebuilding the engine. Cars got a dirty title with previous wreck. Might look for similar generation wrecked car with lower miles and cannibalize this one.

All my stuff I ordered should be here today so i'll play around with it tonight.

Thanks
Jeremy

I've found, the best indication of a plugged cat is the engine runs fine when cold but runs sluggish with very noticeable loss of power as it gets hot. If yours still has power when it gets hot, I doubt the cat is plugged.

At 200K miles some cars are just throwaways, however, if you know the car and all else is in great to perfect shape, buy a cheap wreck with a good motor and change it out. A days work and you'll be heading toward 300K.

Henry

Henry

junk
07-05-2015, 10:41 AM
Well guys I found a leak. I'm hoping it's what's causing the problems. I picked up a cooling system pressure gun and found this pool of antifreeze once I pressurized the system while cold. I'm guessing on a warm engine the antifreeze was evaporating quickly and that's why I never saw the leak before. So I'll keep checking levels, but I'm hopeful this is my concern.

-Jeremy

1608416085

Henry
07-05-2015, 11:19 AM
Well guys I found a leak. I'm hoping it's what's causing the problems. I picked up a cooling system pressure gun and found this pool of antifreeze once I pressurized the system while cold. I'm guessing on a warm engine the antifreeze was evaporating quickly and that's why I never saw the leak before. So I'll keep checking levels, but I'm hopeful this is my concern.

-Jeremy

16085

Gee, let's change the car; let's change the engine; oh, shit; let's tighten (or replace) the FRIGGIN hose clamp!

You beat this one.

Henry

junk
07-05-2015, 08:48 PM
Henry - I thought the exact same thing. DUH Always start at the basics and go from there.

These subaru's are notorious for head gasket issues, so I automatically go for the kill. Also it's been so intermittent and I never noticed a leak so hear again i go for the kill.

Let hope it was just this and she can keep driving it.

-Jeremy

junk
07-06-2015, 09:55 PM
Well I checked the car tonight and it's doing the same thing. Low on coolant and has pressure or vacuum in the radiator when you pull the cap. Back to square one. I'll look for more leaks and run a hydrocarbon test.

Atleast I have something to keep me busy!!

junk
07-26-2015, 09:36 PM
Friday the car was overheating on my wife. Well I tore it all down this weekend. I replaced the a/c condenser cause it was filled with little rocks and I thought it would be blocking some air flow and killing the a/c when driving slow. Not to mention it wouldn't be helping the cooling issue.

Since I had the radiator out and had to refill it I did some more tests. I ran a block test/hydrocarbon test and it seemed to come back clean. I pressurized the cooling system and found a leaky thermostat housing gasket. I swapped it out for another one and it seems ok afterward.

I ran the car around a little bit saturday and it was running warmer than usual, but ran very stable. I'm thinking I didn't get it burped well. So I topped off the radiator and now sunday it seems fine. We'll run it around this week and see how it does.

-Jeremy

junk
07-28-2015, 07:38 AM
Quick update. Checked car yesterday and seemed to be running at normal temp range. Checked antifreeze and it was slightly down if any. I added UV die in it. Figured the UV die will tell me where there is a slight leak I'm not finding.

My latest theories are I overtightened the thermostat plastic housing thus causing a leak or the car has trolls and I'll need to do a ceremony from the old country to clear them out.

-Jeremy

Henry
07-29-2015, 09:57 AM
Quick update. Checked car yesterday and seemed to be running at normal temp range. Checked antifreeze and it was slightly down if any. I added UV die in it. Figured the UV die will tell me where there is a slight leak I'm not finding.

My latest theories are I overtightened the thermostat plastic housing thus causing a leak or the car has trolls and I'll need to do a ceremony from the old country to clear them out.

-Jeremy

I say good with a ? mark which stands for got my fingers crossed for you.

A/C? You know the thing will run hotter with the a/c running. Also, soon as you turn on the a/c or defroster, you should hear a fan(s) start. Are your fans working properly and all the time (when needed)?

If it were mine, I would run it with the a/c unplugged, knowing that alone would make it run cooler.

I think the UV dye is a good idea.

Henry

junk
08-03-2015, 03:15 PM
Henry, I'm a fat guy and if I have to ride in the car at all the AC has to work top notch! :thumb::thumb:

I checked it last night after getting back from camping and it seemed right. So I'm crossing my fingers that maybe it's fixed.

- Jeremy

junk
08-11-2015, 07:27 AM
Checked it again. Levels seemed OK. I'll check again tonight. I'm not going to claim victory, but I'm not planning to send it to the crusher anymore.

-Jeremy

junk
08-28-2015, 09:53 AM
Ok temps been reasonable, but higher than it used to be. I put a new Subaru thermostat in it last night and refilled the radiator. I ran around the engine with the UV light looking for leaks and came up with nothing. We'll see how it goes this weekend.

I update this so in case anyone else ever has this same issue.

Jeremy

junk
09-01-2015, 06:21 AM
Drove the car over the weekend. It seemed to run fine. Just like it used to. I think between an aftermarket thermostat and some leaky radiator hose fittings I now have it back to normal.

I'm normally not a put factory parts back on kind of guy, but thermostats I'm wondering about. I run ford thermostats in my ford diesel trucks and now I'm going to start running Subaru thermostats in my Subaru's. The Subaru thermostat felt heavier than the aftermarket. I wish I'd of weighed them. Seemed quite noticeable.

So now we'll just keep running the wheels off this thing. I'm hoping to hit 300K. :steering:

Jeremy

Henry
09-02-2015, 07:28 AM
Drove the car over the weekend. It seemed to run fine. Just like it used to. I think between an aftermarket thermostat and some leaky radiator hose fittings I now have it back to normal.

I'm normally not a put factory parts back on kind of guy, but thermostats I'm wondering about. I run ford thermostats in my ford diesel trucks and now I'm going to start running Subaru thermostats in my Subaru's. The Subaru thermostat felt heavier than the aftermarket. I wish I'd of weighed them. Seemed quite noticeable.

So now we'll just keep running the wheels off this thing. I'm hoping to hit 300K. :steering:

Jeremy

I'm following what you have to say about the issue. Glad you have it worked out for at least the next 10 thousand miles.

What are you working on and how's the truck?

Henry

junk
09-03-2015, 07:07 AM
Henry,

I do believe this is fixed. Temps are running right where they used to. So I'm pleased with that. Through this I also replaced the a/c condenser because it was plugged with rocks. Well I used the cheapest condenser I could find and it appears to work fine. A/c is as cold as ever. We'll see how that holds in for the long haul though.

Haven't' been doing much automotive related as of late. Been working on the house. We remodeled the kitchen this spring and over the summer started working on the kids rooms. They didn't have usable closets so we are moving their closets and fixing some old plaster that was starting to fall. We still have to redo our laundry room and then finish up with a bunch of painting. I'm hoping to have this all wrapped up in the next couple months.

I'll throw an update on the pickup in that thread.

Thanks
Jeremy

1651716516

junk
09-14-2015, 10:12 PM
Well thought it was fixed. Ran the car 8 hours to the black hills of South Dakota. And it started loosing water and pegging the temp gage. If I kept if filled with water it ran fine. So I filled the water every morning and typically after lunch. Otherwise car ran fine.

When I got home I put pressure on the system and found a small leak on the top radiator hose at the engine again. Once again I tighten the hose clamp up and seems to have stopped that leak. Over 5 minutes it seems to loose 2-3 PSI and I can't find a leak. The head gasket tests I've done seem to come back negative. So we've once again been driving it to and from work. 40 miles a day. Runs fine. I've been checking the water and it's not filling the coolant reservoir this time. Seems to be running normal. So we will see what else pops up.

It's probably not going to far from home anytime soon or maybe ever again.

This video could literally be my family. Same exact car, color everything. My 9 year old twins rode in this thing since they were born.
Mitch Mobile (https://youtu.be/57nTRQUli-Y)

tomsteve
09-15-2015, 04:43 PM
have ya checked hoses to heater core?
pull dipstick and check oil.also stick yer finger in where ya add oil, with the engine off, and wipe around.waterthat gets inside an engine will steam, goto highestparts of engine, and a milky sludge will form.
. pull and check plugs. all plugs should look tan. whites not good.
but check hoses going to heaterrcore first.

if its an aluminum head and temp was pegged it could be a cracked head.

was head gasket test done on hot or cold engine?

junk
09-16-2015, 08:02 PM
Tomsteve thanks for the suggestions. I think I've gone through most of them.

-Heater hoses look good. They are original, but look good. Heater core appears OK
-Oil looks fine. Just changed it and it was fine. Oil fill looks fine. No milky stuff.
-Head gasket check was done at various times with cold and warm engine. I don't know If it was hot.
-I did not pull any plugs yet.

So I went out tonight and checked it. It seems fine. Reservoir level was fine. Radiator was full. Wifes reported no weird temp readings.

So once again i think it's Ok. We'll keep using it for work and see how it goes.

-Jeremy

tomsteve
09-17-2015, 12:53 PM
if ya werent losing coolant id think a few things.
tstat, even though new it could be a problem. with my saturn ive heard people have problems is a stant brand isnt used.learned that after replacing mine with a non stant brand and having problems persist.
same thing with waterpump.
with no coolant lossan air pocket can cause fluctuating temps.
aslo a faulty temp sending unit.

reading hoses "look good" concerns me. the wear happens internally. something i did with a taurus i owned with a mysteryleak where i was ready to tear the heads off:
hadda friend over that knows more than me. we got it up on ramps, let it warm up, then he had me get in and get it up to 2500 rpms while he went underneath on a creeper. lo and behold, withthe added pressure a lil pin hole leak in heater core hose showed itself. it wasnt going to show for crap while the engine was idling as there waxnt enough pressure in the system.

tomsteve
09-17-2015, 01:00 PM
any chance youve done some surfin for info here?
http://www.subaruoutback.org/forums/

junk
09-22-2015, 06:33 AM
Thanks again for the suggestions tomsteve. I'm waiting and seeing at this point. Cars been running fine. Radiator is always full and coolant bottle level never changes. So I think I'm ruling out head gasket.

I'm still not sure what was happening. My theory is I had a hose leak that was more pronounced at higher RPM's. Maybe? I'm waiting this out a little bit to see how it goes. Then I'll probably change all the hoses just for good measure.

I'll update if anything changes. Or I finally find the smoking gun!

Josh C
11-25-2015, 01:30 PM
You should inspect the rubber seal on the radiator cap and the mating face on the filler neck. If it is missing a chunk or obviously worn you may be losing coolant there when the system pressures up.

Skalabala
01-07-2016, 03:09 AM
Did that model came out with a coolant fan computer module?
Did you ever check the water temp with an external temp device?
It could still be a head gasket on one of the banks, it could be a crack that opens up when the car is really warmed up etc.

junk
01-07-2016, 10:51 PM
I appreciate the ideas!

I did end up putting head gaskets in it over new years. It's running well and doesn't see to be pushing coolant out any longer. There was a visible area in the head gasket that was suspect. So I'm confident I had a small leak when the car was warm.

Only concern I still have (and it could be me being paranoid) is the temps run fine when idling or running 60 mph. But if your going around 30 MPH at 1500 RPM the temp gage runs a little warmer than it used to. I need to get my code reader on there to see what the water temps are actually doing vs watching the gage. The thermostat is fairly new, but was in there with the bad head gasket, so I'm concerned it may be bad?

Thanks
Jeremy

Henry
01-08-2016, 09:05 AM
I appreciate the ideas!

I did end up putting head gaskets in it over new years. It's running well and doesn't see to be pushing coolant out any longer. There was a visible area in the head gasket that was suspect. So I'm confident I had a small leak when the car was warm.

Only concern I still have (and it could be me being paranoid) is the temps run fine when idling or running 60 mph. But if your going around 30 MPH at 1500 RPM the temp gage runs a little warmer than it used to. I need to get my code reader on there to see what the water temps are actually doing vs watching the gage. The thermostat is fairly new, but was in there with the bad head gasket, so I'm concerned it may be bad?

Thanks
Jeremy

Congrats on being persistent with this thing, especially with all the miles it has. Most would have driven it to the crusher by now.

I say, change the stat and opt for one by STANT.

Another thing comes to mind when at idle is airflow through the fins on the radiator. Are things clean between the fins? You follow? If the fins have crap built up then your airflow at idle (standing still) will be less versus forcing air through the fins while driving. You can blow the fins out, not with compressor air but with your blower means on a Shop Vac.

Next would come the fan(s). If the car has A/C, you can make the fan(s) run in DEFROST mode. Leave the DEF mode on and see if the fan or fans are working. Then check and see if that keeps the temp down at idle.

Proud of your efforts.

Henry

Skalabala
01-08-2016, 09:16 AM
How did the water ports look inside the block and heads.
Using your reader is still not an external device temp measurement bud :)
And are you using coolant from the agents? And is the thermostat from the agents?

junk
01-08-2016, 09:36 AM
Cooling system in the engine looked clean. No excessive crud or buildup.

Because this thing was so flaky on overheating I've replaced a lot of parts for just basic maintenance. The cars got miles so it wasn't too hard to justify replacing parts. I'm under $400 even doing head gaskets, cooling stack, hoses etc.

Cooling stack is new. The old ac condenser and radiator were full of rocks. Now the a/c condensor and radiator were low cost aftermarket units. So there could be reduced air flow through them compared to Factory subaru parts. Although the factory parts were probably 30% blocked by rocks.

Thermostat is a factory subaru Stat. I do have a Stant that looks exactly like the Subaru stat. I may swap it back in. Or just get another new Subaru thermostat.

Cooling fans do work. I've checked them.

I've stuck with it because overall we still like the car. It's got miles, but we know what issues it has. It's not rusty. Doors are tight. All the options still work. So overall still a solid car. It would cost us 15K min to make much of an improvement and it's just not worth it yet.

Thanks
Jeremy

Phil V
01-08-2016, 11:28 AM
Does the engine use coolant ? (level in reservoir drop?).

When you say " it pegged the temp needle " do you mean the engine was blowing steam out the radiator cap (or coolant reservoir cap) ? When you had the head off did you have it/them professionally tested for minute crack(s) ? Did you have the head flatness professionally checked and or resurfaced to make sure it's not warped ? Did you replace the water pump ?

junk
01-08-2016, 12:09 PM
Yeah when heads were off they went to the machine shop for a mill and inspection. Both passed.

Waterpump is new last spring before all this started as part of a timing belt kit. Old pump was failed and put a slight groove in block. I've wondered if the failed water pump created the head gasket issue.

When gauge "pegs" hot it was never doing classic overheat symptoms. Never any steam or coolant overflow. It would just be low on coolant. You could immediately remove the cap with your bare hand and top off the coolant. Then all would be well for next day or week.

I think the main culprit here was a bad head gasket all along.

Thanks
Jeremy

Phil V
01-09-2016, 01:56 PM
Yeah when heads were off they went to the machine shop for a mill and inspection. Both passed.

Waterpump is new last spring before all this started as part of a timing belt kit. Old pump was failed and put a slight groove in block. I've wondered if the failed water pump created the head gasket issue.

When gauge "pegs" hot it was never doing classic overheat symptoms. Never any steam or coolant overflow. It would just be low on coolant. You could immediately remove the cap with your bare hand and top off the coolant. Then all would be well for next day or week.

I think the main culprit here was a bad head gasket all along.

Thanks
Jeremy

Sounds like you're right. There are different degrees of a head gasket being bad. A few years ago I had a Ford T-Bird that developed a bad head gasket. It would never actually overheat, just the temp gauge needle would go up quite a bit higher than normal and it didn't do it all the time. Sometimes it ran normal. But over a period of a couple weeks it got worse.

junk
01-10-2016, 09:05 PM
So the other day i took the time and put the scan tool on the 2004 subaru car to look at the temps from the computer. Driving around in 0 degree wether it hit 96 to 97 degrees C. That's about 205-207F. Seemed high for ambient temps. So I put the tool on my other subaru a 2003 with the same engine. And it also hit 96 C. So while the 2004 gauge swings all over but only hits 205 the 2003 cars gage is rock solid and hits 205 also.

It appears we don't have an issue. Only concern is it will be hard to spot a possible overheat since it does move so much.

Yeah this thing was completely fine for weeks then we'd have an issue. I also did several head gasket tests and never had a good result. I finally changed it because we kept getting increased temps and an overheat on highway driving and consistent low coolant.

What type of thunderbird? One of the newer ones? I really like those.

Jeremy

Skalabala
01-13-2016, 01:07 AM
The block could be warped or collapsed. Did you check the block deck?