My 90' Legacy is overheating sporadically. The problem starts once the car is good and warmed up for a while. The temp gauge suddenly climbs to high, during this time the heater blows cold air. All of a sudden the temp gauge will start dropping, then the heater will start blowing hot again. It will do this on and off during trips without any sort of time pattern. The problem is getting worse with longer hot periods. I installed a new thermostat. This didn't help. The fans both work. Coolant is full but I can smell that anti-freeze odor. The system doesn't seem to build up pressure. I can't find any leaks. I'm stumped!

 

Billtom, North Carolina

I had the same problem on a 91 Subie. It turned out to be a bad head gasket. Your 2.2 motor does not have a reputation of developing a bad head gasket like later model Subarus do, but none the less the 2.2 will blow a head gasket.

 

The major clue was your saying that the heater blows cold air. That results from the bad head gasket allowing exhaust gas to enter the cooling system. Enough gas causes a big bubble in the cooling system. A big bubble does not flow through the heater core like radiator coolant does, so no flow, no heat. The hot exhaust gas also causes the motor to over heat.

 

If the HG is not completely blown, you can prolly drive the car on short distance trips, and not at high speed. You must keep an eye on the temp gauge, it it starts to over heat, you will need to pull over and let the motor cool down. Otherwise, driving with an over heated motor, will ruin the motor, but I bet you prolly know that.

Thanks for the information. I was sure hoping it was something minor. I can't complain though, I got the car for free from my Mother in law. Putting some work into it will be worth it. The car is in good shape other than this problem.

At the time of over heating, suggest you look to the inside of the radiator overflow container. If you see bubbles, then it confirms a bad head gasket.

 

I have read where others having your problem, have loosened the vent screw on the opposite end of the radiator from the rad cap. Loosening that screw vents off some of the exhaust gas that accumulates in the cooling system, and helps the engine from not over heating. Some of the coolant is lost doing this. It's certainly a band-aid approach, but a consideration.

 

I see that you are new on this forum, and glad to have you join us. There are many others on this forum that are Subaru pros that know a lot more about Subies then me. I am sure you others will have good advise for you as well.

How many miles? It is possible the water pump is inefficient, as the impeller can wear out and corrode, and cause cavitation of flow.

 

Do look for bubbles in the radiator.

The car has 112,000 miles on it. I got the car about 1 1/2 years ago. I'm not sure if it matters but the car would sit for months at a time and was barely driven for 8 years before I got it. I'll look at the coolant and see if there are bubbles. I am sure that this is the original water pump so I wouldn't be surprised if it has some corrosion.

sounds like HG but make sure first.

 

the HG are actually easy to do on this car (as far as headgaskets go) and does not require removing the motor, can do them right in the engine bay.

The car has 112,000 miles on it. I got the car about 1 1/2 years ago. I'm not sure if it matters but the car would sit for months at a time and was barely driven for 8 years before I got it. I'll look at the coolant and see if there are bubbles. I am sure that this is the original water pump so I wouldn't be surprised if it has some corrosion.

 

the telltale signs of bad head gaskets are bubbles in the overflow when running hot, and black gunk in the overflow. that along with the ''no heat'' are classic signs.

 

but considering the fairly rear failure rate of the head gaskets in the 2.2L engines, i would replace the radiator cap, t-stat, (if you have not yet) and refill the coolant properly. it may not help, but with a low mileage engine it will not be wasted since you, or someone, will re-do the head gaskets and have a great engine for 150k miles. you should also do the timing belt, all idlers, and water pump, as well all the seals, oil pump, and cams.

 

the only down side to all of this is the that resale value is not very high. so you will have to drive it to get your money out of it. the car is not worthless but it has a limited value. but fix it and drive it for 50k - 70k miles and you will be glad you did.

Replacing a few parts isn't too bad. I drive 40 miles each way to work so this Legacy performs well for a work car. It keeps me from piling up miles on my 2010 Forester and isn't bad on gas. I'd be happy if I could get 3 or so years out of it. I appreciate all of the advice, it's a huge help to hear from other subie enthusiests. I guess it's time for me to get the tool box out and get busy.

Sounds like a head gasket to me - that's pretty much par for the course when they blow.

 

1. Pull the engine. You don't want to do this in the car.... trust me.

 

2. Have the heads resurfaced and new valve stem seals installed *at the least*. Have the machine shop check the valves, seats, and guides as well so you know where you stand.

 

3. Use ONLY Subaru head gaskets, manifold gaskets, and exhaust gaskets. On these engines - it's a gamble you don't want to take.

 

4. Use ONLY Subaru thermostats. Other's have a high rate of failure.

 

5. Get your complete timing belt kit from "theimportexperts" or "mizumoauto" on ebay. Get one with a water pump, etc. Around here the consensus is that you should change all the idlers every time you do the belt.

 

6. Also replace the cam carrier o-rings (not in the kits). Get these at the dealer.

 

GD

the only down side to all of this is the that resale value is not very high. so you will have to drive it to get your money out of it. the car is not worthless but it has a limited value. but fix it and drive it for 50k - 70k miles and you will be glad you did.

 

Not to rain on your parade........but

I'm thinking that your car is 21 years old. At some point you have to be concerned about how much repair money you are willing to put into a car that is this old. Like said above, unless you are wanting to drive this car for a long time, and put on a lot of miles, you may want to consider the value of dropping a lot of good money into this car.

 

I have seen a number of old complete respectable decent looking cars that have just entered a wrecking yard. They weren't wrecked, but asking the yard owner, and he will tell you that the engine or trany is bad. It's something to think about.

90 lego w/ 112k miles

 

sale price ===== $ 00

timing kit ===== $180?

head gaskets == $ 75?

machine shop == $145?

seals ======== $ 50?

total cost ===== $450

 

drive it 50k miles and sell it for 500$.

or

drive 100k miles and sell it for 500$.

 

works for me.

 

it sure sounds like head gaskets but it is hard to imagine how that could happen to a ''old lady'' car w/ 112k, rarely driven. i'd check it out really well before i pulled the heads.

Edited February 11, 201115 yr by johnceggleston

Sitting or driven infrequently over the last many years, .. Then driven for awhile uncovers the damage of coolant which has turned corrosive to the aluminum. One area between two coolant passages short-circuit the cooling or most likely between combustion and one. What I mean is the casting of heads often is that the coolant passages taper wider toward the inside. The gasket must fail when this happens.

Edited February 12, 201115 yr by Fuzpile

Yes - sitting or infrequent driving can and will destroy head gaskets. I've seen it quite a few times on older stuff.

 

GD

na/different engine

Edited February 13, 201115 yr by Fuzpile
unhelpful

I have considered rebuilding this motor. If I pull it, what the heck, I may as well throw in a crankshaft kit, cam bearings, and a complete set of seals. What is the comparison to buying a factory rebuilt engine vs. doing the rebuild myself, or maybe getting a junkyard motor. I'm a little skeptical about a used motor since there is no way to tell how it was run or maintained.

you could get by just doing the HG.

the ej22 engine, which you have is surprisingly good, even with trouble. you can get a replacement for 300$ , 150$ if it is a u-pull-it. swap the engine and drive on .

 

but chances are good that it will run forever if you replace the gaskets. not hard to do but still a job.

 

for me it would come down to the cost of the replacement engine vs. the parts. but gaskets are cheap and do not compete with the the replacement cost of an engine. regardless of what you choose, re-place or re-gasket, you will want to replace the timing belt and all of the idlers.

 

good luck.

I disassembled the Timing belt and water pump assembly. I hoped that maybe it could be the water pump as suggested in some of the posts. Found that the water pump had a lot of play in the impeller shaft. I replaced the pump along with the timing belt and idlers. I held my breath and took a drive on the highway. The car ran great without any overheating problem. It looks like this old subie has some miles left on it yet. Yipeee!

Thanks to all of the people that replied with their posts. It helped me a LOT!