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84 gl hatchback overheating

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I just bought this car when i finished driving it I could hear boiling in the radiator and it was really hot. the previous owner said it needs another fan as it only has 1 right now.

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First I would check the coolant levels and see if there are any leaks anywhere


Then Id just listen and see if the fan comes on when the temps rise to around 50% or so on the gauge.  if it goes higher and no fan, check on that first.


third I would check the thermostat.  buy a subaru one from the dealer.  they are about $4 more, but well worth it, there have been many people on here, myself included, that have tried aftermarket ones and had to replace them in days.


it could be a head gasket, but probably best not to jump right to the worst conclusion, check the other stuff and report back.

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No leaks I could find. My dad and I did find like 3 thermostats in a box in the trunk so that could be it. Also there is a switch on the dash that controls the fan that I switch on before I start the car.

Edited by bigbronate

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Doubt it's the thermostat if you've found three in the trunk. It's more likely that he bought a new one swapped it out didn't work, bought a second one just to make sure, then took it out all together.


The reason he hooked up the wire to your fan is because your fan sensor is out.


Sounds like he already went through all the steps of trying to figure out what was causing it to overheat and came up with a blown head gasket so he pawned it off on you. Hope I'm wrong


Check your oil for a chocolate milk color.

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No, there is no fan switch in car unless previous owner wired one in. 


To get it working as it should, you need to determin if it it is the fan motor or Fan Sensor switch located on the passenger side of the radiator.  Do a search on the topic above on the tool bar under... "Search"  enter topic (fan sensor or switch) for an EA-81 engine and see what you find.  Jumping 12 volt wire to the fan should get it to turn, if it does than it is probably your sensor.  Almost easier to take out the 4 bolts and remove fan and work on bench, run a positive and neg. wire to two wires on fan motor and see if it turns when energized from car battery.  Doesn't, bad fan motor as seller said.    The sensor wire that connects to sensor can be jumped to ground which will by pass the sensor and start the fan even if it isn't up to temp.  I like to use aligator clips, and turn key just before "start" and see if fan comes on... read in search.. good simple how to test in there. 


If the fan is running but still overheating...

Your radiator could also be plugged up... they are about $130. new... so not to bad, Also the radiator cap may not be holding pressure (old) or look inside top of radiator where the cap makes a seal, it could be crudded up... clean that radiator sealing surface and the rubber seal on the cap, with a green scotch bright pad so the radiator cap makes a positive seal which builds pressure which raises boiling point so it won't boil... if that is the issue.  


My 84 has only one fan.. that is fine if you don't have A.C.  I believe. 


Also, need parts?  Rockauto.com  is a great place to go.  They ship fast and have some killer deals.  


These little engines don't like to be overheated.. that is a taboo but their tough so as long as they are pushing fluid in there that is as far as you want to push it, stay out of red area on temp. gauge. The loss of water and overheat is bad.. 


These are great little cars and sounds like you are learning.  Chasing these issues down and fixing them are great experiences,  it's a learning process and don't be upset by these hick-ups, see them as a challenge, a chance to learn.  


Hope this helps, Enjoy. 

Edited by Indrid cold

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I wouldn't replace the fan sensor if the switch is turning on the fan, not yet anyway. Track down the over heating problem first. Those fan switches can be spendy for such a little thing. Plus, I've seen guys bust off the fitting, usually on radiators that needed to be replaced anyway.


here are some things you can do to check for a blown head gasket.


1. run a compression check. One cylinder should be noticeably lower than the rest. This doesn't always mean a blown gasket. It is an old car, it could mean a couple of things.


2. Your radiator will build up pressure, more pressure than a normal over heating car. I've had them blow the radiator cap across the shop when I tried to take it off 30 min after I shut the car down.


3 Oil may have a chocolate milk look to it. I've only had this happen once and I've blown a lot of them.


4. steam in your exhaust. Only happened once and it sprayed water out the crack in the exhaust manifold.


you can always run with your radiator cap on loose to help keep the radiator from building up pressure. removing the thermostat also helps in this department.


Definitely, check all the easy stuff first before you decide it's a head gasket. pulling the heads off these things is a pain in the butt.


I ran with a blown head gasket for almost a year, loose radiator cap, no thermostat and 30 min to get wherever I wanted to go. Ah, those were the good ol' days.

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