wildseamus Posted February 1, 2012 Share Posted February 1, 2012 (edited) Have 91 2.2 L legacy. Overheating problem that I beleive is HGs. Top hose hot bottom hose cold, new t-stat, fan turns on, new rad cap, system has been burped....sometimes blows hot air sometimes cold air. Coolant bubbles in rad while engine heats ups, water vapor in exhaust. It overheats after about 6-8 miles of highway driving w/ air temps in 30s, coolant spills into overflow tank which overflows and spills coolant on the ground or even pops the reservoir cap, the coolant in the overflow is usually cool. Don't want to spend $ on a HG job as car's days are numbered. Will I benefit from removing the t-stat all together or drilling small holes in it? Do they make a rad cap that bleeds air? Trying to buy a little time as we're picking up a newer car from friends in a few months and it only needs to drive 7 miles to and from work 4 days/week until then. Edited February 1, 2012 by wildseamus Quote Link to comment Share on other sites More sharing options...
bstone Posted February 1, 2012 Share Posted February 1, 2012 What sort of t-stat did you put in? Is it an actual Subaru t-stat or an aftermarket part? Quote Link to comment Share on other sites More sharing options...
wildseamus Posted February 1, 2012 Author Share Posted February 1, 2012 Non oem t-stat, I just tested the original subaru one and it tested out fine. I had the problem with that one it too....so I don't thinks it's t-stat. Quote Link to comment Share on other sites More sharing options...
bstone Posted February 1, 2012 Share Posted February 1, 2012 Non oem t-stat, I just tested the original subaru one and it tested out fine. I had the problem with that one it too....so I don't thinks it's t-stat. Aftermarket (non-OE) t-stats cause overheating in 100% of the cases. You must absolutely get an OE t-stat, burp the system, and try again. Quote Link to comment Share on other sites More sharing options...
1 Lucky Texan Posted February 1, 2012 Share Posted February 1, 2012 ******Coolant bubbles in rad while engine heats ups, water vapor in exhaust.****** likely HGs. There is a chemical test to confirm combustion gasses in coolant, from the auto parts store. Also, one of the 4 plugs MAY look different from the other 3 if you have coolant out the tailpipe. I think coolant is bad for O2 sensors and cats so, try to get this fixed soon. Quote Link to comment Share on other sites More sharing options...
idosubaru Posted February 1, 2012 Share Posted February 1, 2012 (edited) not much you can do to nurse them along. i have not seen thermostate removal help, but maybe each case is different. the EJ thermostat set up isn't favorable to remove it since you also remove the gasket which seats around the tstat. i doubt you have anything to gain but you've got nothing to loose to try either! Aftermarket (non-OE) t-stats cause overheating in 100% of the cases. that is not true. i don't use them or recommend them but they don't fail 100% of the time, not even close actually. they're used all the time without issue, again not saying i recommend it because i don't use them. Edited February 1, 2012 by grossgary Quote Link to comment Share on other sites More sharing options...
Rooster2 Posted February 1, 2012 Share Posted February 1, 2012 not much you can do to nurse them along. i have not seen thermostate removal help, but maybe each case is different. the EJ thermostat set up isn't favorable to remove it since you also remove the gasket which seats around the tstat. i doubt you have anything to gain but you've got nothing to loose to try either! that is not true. i don't use them or recommend them but they don't fail 100% of the time, not even close actually. they're used all the time without issue, again not saying i recommend it because i don't use them. Aftermarket thermostats will work fine. I am using one now for the past three years. I just made sure to buy an expensive aftermarket unit that has the large and long spring mechanism like the OEM model. It is the cheapie stats with the short spring, that I think are the trouble makers. Quote Link to comment Share on other sites More sharing options...
the3rsss Posted February 1, 2012 Share Posted February 1, 2012 Well. You can take out the thermostat and take the gaskets off the rad. Cap. Check coolant every day. Run it till it dies. Goodspeed! Quote Link to comment Share on other sites More sharing options...
the3rsss Posted February 1, 2012 Share Posted February 1, 2012 Godspeed! Quote Link to comment Share on other sites More sharing options...
porcupine73 Posted February 1, 2012 Share Posted February 1, 2012 You can kind of blank out the thermostat by cutting the guts out with a dremel or similar tool. That leaves you with the empty metal disc so you can keep the gasket in place. I'm trying to think if it might be better to just run it with water and maybe water wetter instead of glycol (assuming there is no freeze risk where you are), so if it gets in the oil or through the exhaust that would be not as bad as if coolant is in there. Quote Link to comment Share on other sites More sharing options...
johnceggleston Posted February 1, 2012 Share Posted February 1, 2012 the reason the top hose is hot and the bottom hose is cold is because there is an air lock in the cooling system. or more likely an ''exhaust gas lock''. the exhaust gas builds up in the system and eventually it creates an exhaust bubble so big the coolant will not flow. if you loosen the vent plug on the passenger side of the rad where the top rad connects this will / should / might allow the gas to escape preventing the air lock. there is also a rad cap with a vent clamp on top which will do the same thing if you drive with it ''un-clamped''. i forget the name brand. but as long as the exhaust gas escapes the system the coolant should flow preventing the ''over heat'' and the no heat out of the heater. but you will have to keep an eye on the coolant level. check it every AM until you get a feel for how much you are loosing. then check it and add as often as needed. depending on where you live, you might ''thin out'' or water down the coolant you add. keep it strong enough to prevent freezing but thin it enough to save some $. how long before you buy a car? good luck. Quote Link to comment Share on other sites More sharing options...
wildseamus Posted February 2, 2012 Author Share Posted February 2, 2012 Thanks for all the advise, I'm going to try a few things tonight and see what happens. I took the original OE t-stat and drilled 2 1/16" holes through it to help the gas bypass which I'll reinstall. I'll reburp the system and try leaving the vent plug a little loose. The only real thing I haven't completely ruled out is the rad itself. I pulled it out and ran water through it and it seemed to flow alright but I don't really have anything to compare it to. Any tests I can do with in to rule out the rad....they're pretty inexpensive but don't want to buy one if I don't have to. My radiator has 2 small outlets on the driver side (top and bottom) that don't connect to anything.....just capped off with rubber stoppers....the stoppers are cracked...so I just duct taped them up. Any idea what these are for? I have a manual tranny, thought maybe they would somehow be used for an AT as it appears the radiator will fit an AT 90-94 legacy as well. Buying a newer car in late March from relatives so trying to make it last a few more months....I've had her for 14 yrs:( Quote Link to comment Share on other sites More sharing options...
johnceggleston Posted February 2, 2012 Share Posted February 2, 2012 My radiator has 2 small outlets on the driver side (top and bottom) that don't connect to anything.....just capped off with rubber stoppers... this sounds like it is a replacement rad, or did they use the AT rad for both AT and MT cars from the factory?? Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted February 2, 2012 Share Posted February 2, 2012 Pretty sure the MT cars got a radiator without the heat exchanger. Sounds like a head gasket. Thing is, the EJ22 is robust enough to pop a head gasket and still go strong for another 100k miles after you fix it. I'd fix it. Quote Link to comment Share on other sites More sharing options...
wildseamus Posted February 2, 2012 Author Share Posted February 2, 2012 Burped coolant system and installed modified t-stat. I ended up drilling a couple 1/16" holes and a couple 1/8" holes in the t-stat to allow exhaust gas bypass. So far so good...after driving it for over 30 miles last night no overheating...it use to overheat in just 6-8 miles. When it would overheat the bottom hose off rad was rock hard. With modified t-stat both top and bottom hoses hot and soft and heater blows hot.Temp stayed in the normal to ever sightly below normal range, air temps in the 20s. Once I get the newer car I plan on pulling the engine and replacing gaskets and seals....as an educational experiment as my current car is a 02 Forester. I gave this car to my wife a few years ago and would like to keep it alive and learn from it. It only has 180K, not bad for a 91. Quote Link to comment Share on other sites More sharing options...
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