dm88 Posted May 26, 2012 Share Posted May 26, 2012 So i put in a new head gasket because i was getting bubbles in the coolant. so i finished up and fired her up, filled her up with coolant and took it around the block. it overheated, luckily i was close to home so pulled back in to my garage and popped the hood and could see bubbles in the expansion tank....i nearly cried... then i though maybe its just air so i opened up the bleed screw and added a lot more coolant but i also noticed that the expansion tank filled up almost to the top (this was before i opened the bleed screw) then i heard the coolant getting sucked back in and the upper rad hose got really skinny. so i filled it up and took it around the block again and it made it twice around then it started to overheat again so i got back home and looked at the expansion tank and saw it was full to the top again after being empty again. once the car cools down it gets sucked back in. maybe a bad rad cap? THANKS Quote Link to comment Share on other sites More sharing options...
Caboobaroo Posted May 26, 2012 Share Posted May 26, 2012 Try replacing the cap with a OEM one. I have seen many aftermarket ones that don't function properly and can cause major problems. Since you mentioned a bleeder screw, sounds like you have the EJ25D. Did you make sure to burp the cooling system before taking off in it? Trapped air can cause the temp gauge to head up as well. Quote Link to comment Share on other sites More sharing options...
dm88 Posted May 26, 2012 Author Share Posted May 26, 2012 (edited) yup sorry forgot to mention 98 legacy ob. Ok i hope i can still get one today. but are those symptoms of a bad rad cap? Edited May 26, 2012 by dm88 Quote Link to comment Share on other sites More sharing options...
Caboobaroo Posted May 26, 2012 Share Posted May 26, 2012 If the cap isn't holding pressure, it can bleed out into the overflow when the system starts to pressurize as you're driving. The air you might be seeing could be air trapped in the cooling system if it isn't properly burped as well. Quote Link to comment Share on other sites More sharing options...
johnceggleston Posted May 26, 2012 Share Posted May 26, 2012 could be air trapped in the cooling system if it isn't properly burped as well. improper filling and failure to burp is the leading cause. Quote Link to comment Share on other sites More sharing options...
dm88 Posted May 27, 2012 Author Share Posted May 27, 2012 im pretty sure i got all the air out. i filled it to the top while it was at operating temp from both the cap side and the bleed side. now whats happening is it overheats when ic ome to a stop not while im moving rather quickly. i didnt get a rad cap because the dealer is closed but this makes me think its not the cap. what else could it be? i did put in a non subaru tstat but i tested it (in water on my stove) before i put it in. Quote Link to comment Share on other sites More sharing options...
chucktile Posted May 27, 2012 Share Posted May 27, 2012 Take off the radiator cap, start the car, fill the radiator. Leave the cap off, let the car run until the thermostat opens, then turn the heat on high. Give it a minute, then top off the radiator. This is how the service manual says to do it and is the only way it works for me. The cooling system holds two full gallons, if you did not put two full gallons in it is not full and will overheat very quickly usually within two or three miles. Quote Link to comment Share on other sites More sharing options...
johnceggleston Posted May 27, 2012 Share Posted May 27, 2012 fans working, sounds like no. Quote Link to comment Share on other sites More sharing options...
dm88 Posted May 27, 2012 Author Share Posted May 27, 2012 Yup fans are working.. I took out the non Subaru t stat and it seems to be better (I just ripped off the spring and copper part and put in just the round part with the gasket...I know it sounds barbaric) ..I think I might still have some air because the temperature is fluctuating... Not nearly the spikes I used to get before the head gasket but it'll climb up to 2/3 then go back down. At least it's somewhat drivable for now. I'm going to wait for it to cool off then fill it with the heater on which I for to. That's probably why I could hear bubbling from behind the vents. Quote Link to comment Share on other sites More sharing options...
Rooster2 Posted May 27, 2012 Share Posted May 27, 2012 I hope your after market T-stat is working properly. I have an after market T-stat in my 98 OBW, but made sure to buy one that cost $30+, with a long large coil spring design like OEM. It is the cheapie T-stats with the short coil design that don't work well, even if tested in water on your stove. I run an after market rad cap with no problem. However, your over heating does sound like a faulty rad cap. With dealer closed over the long holiday, I would recommend after market cap. Buy the most expensive one they sell, for just a couple of bucks more then their cheapest. It is hard to imagine your head gasket job is faulty right after rebuild. Are you sure the heads are bolted down properly?? Quote Link to comment Share on other sites More sharing options...
dm88 Posted May 27, 2012 Author Share Posted May 27, 2012 The only part I messed up was while torquing downt the drivers side head. I go the order down wrong but luckily I was only at the part where you torque down to 54ftlbs then back the bolts off 90 degrees twice. From that point on i followed the correct order. Plus I don't see any bubbles in the expansion tank and it's not spitting out the coolant like it did when the hg was bad so Im t asking a pretty educated guess that my mishap with the head bolts didn't affect it much. Quote Link to comment Share on other sites More sharing options...
dm88 Posted May 28, 2012 Author Share Posted May 28, 2012 ok so now i filled it up again using the proper procedure and im still over heating...it cant be the tstat because it doesnt have one. it cant be the hg because theyre new and plus i have non bubbles in the expansion tank. cant be the rad cap because its new. i dont get it.. this car is starting to really get on my nerves. i can hear bubbling from behind the dash and from the cooling system in the engine compartment once i turn it off and i pop the hood after it overheats. any ideas? Quote Link to comment Share on other sites More sharing options...
uniberp Posted May 28, 2012 Share Posted May 28, 2012 I searched this thread for the word "waterpump". There is no reason to suspect it other than it is the main source of coolant circulation. Maybe the impeller got loose. IDK. Quote Link to comment Share on other sites More sharing options...
chucktile Posted May 28, 2012 Share Posted May 28, 2012 Has there ever been any type of sealant used in the engine? Are the heater hoses behind the engine hooked up properly; in to the in and out to the out? Quote Link to comment Share on other sites More sharing options...
dm88 Posted May 28, 2012 Author Share Posted May 28, 2012 Heater hoses were never removed. I did the hg with the engine in. Quote Link to comment Share on other sites More sharing options...
chucktile Posted May 28, 2012 Share Posted May 28, 2012 Last week I did a timing belt service on a 2000 legacy ej25sohc. Of course I replaced the water pump. The same problem arose. First I changed the aftermarket tstat, problem was still there. The solution was to fill the system according to the service manual, next I had to drive the car with the heat on full blast for a couple miles. Then I parked the car and let it cool. I then opened the radiator and repeated the filling process starting with, starting the car and letting it run until coolant circulates, then blasting the heat and topping off with coolant. It seems that there was air trapped somewhere in the heating system and the only way it was comming out was driving with the heat blasted. Its been just over a week and no overheating. This has never happened to me before and I hope it never happens again. I hope you get it straightened out as I know how frustrating this problem can be. Quote Link to comment Share on other sites More sharing options...
dm88 Posted May 29, 2012 Author Share Posted May 29, 2012 so i burped the system again and went for a test drive. it did fine for really long time and now it over heats on a hill that it would otherwise not overheat. so basically i can drive it anywhere as long as theres no long uphill. i never had this problem before... whats going on!?!? Quote Link to comment Share on other sites More sharing options...
chucktile Posted May 29, 2012 Share Posted May 29, 2012 It sounds as if there is still a bit of air trapped in the system. The only other thing I can think of is air or combustion gasses are getting in somehow. Quote Link to comment Share on other sites More sharing options...
dm88 Posted May 29, 2012 Author Share Posted May 29, 2012 So today my roommate drove it to work about 30 moles away all freeway. He said as soon as he got off it started to over heat but once he turned the ac on and got moving again it cooled back down. Then he pulled in to the parking lot at work and it started to overheat again. Do you think a little bit of air could be causing this much havoc? How would you recommend getting that little bit of air out? I don't really want to drain and refil unless I have to. Also I doubt combustion gasses are getting in because it wouldn't fluctuate like that wold it? Thanks again for all your help Quote Link to comment Share on other sites More sharing options...
johnceggleston Posted May 29, 2012 Share Posted May 29, 2012 it sounds like you have good cooling at speed and not so good at idle or slow speeds after speed. a blockage maybe? was any ''stop leak'' ever put in this engine? is the rad original? blocked radiator? did you flush the rad as soon as you removed it? Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted May 29, 2012 Share Posted May 29, 2012 You said head gasket, not head gasketS... Did you only replace one? Or did you replace both? What brand of gaskets did you use? Did you have the heads milled? How did you clean the block surface? Quote Link to comment Share on other sites More sharing options...
dm88 Posted May 29, 2012 Author Share Posted May 29, 2012 I used blue devil before I did the head gaskets. I replaced the radiator (with a used one) when I got the car in February then did the blue devil stuff. I never used stop leak or any of the other thick stuff. What should I flush it with for it to be the most effective? Any other possibilities? Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted May 29, 2012 Share Posted May 29, 2012 No way to flush Blue Devil out. It basically turns to an almost glass like substance that sticks to every part of the cooling system. The good thing is that it doesn't typically clog things up, like other gasket in a bottle products, because there aren't any chunks in it. But as far as I know there is no way to get it out without taking the parts to a radiator shop and having them acid/chem back flushed and agitated. Quote Link to comment Share on other sites More sharing options...
dm88 Posted May 29, 2012 Author Share Posted May 29, 2012 You said head gasket, not head gasketS... Did you only replace one? Or did you replace both? What brand of gaskets did you use? Did you have the heads milled? How did you clean the block surface? I replaced both with felpro. I didn't have them milled but I checked to see if they were warped. I used degreaser for the surfaces. Even if there was so me gas getting into the coolant why would it go 30 miles fine then overheat on the off ramp? Quote Link to comment Share on other sites More sharing options...
dm88 Posted May 30, 2012 Author Share Posted May 30, 2012 I really doubt it could be the head gaskets because it's notthesame symptoms I had before. it doesn't spike like did with the bad head gaskets Quote Link to comment Share on other sites More sharing options...
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