Mechanics

WHY DOES MY CAR OVER HEAT AFTER GETTING OFF THE FREEWAY

1998 Honda Civic • 179,000 miles

Recently, about a month ago I replaced the radiator in my civic because the radiator had a hole that had started to spew coolant. Other than the leak of coolant the system worked fine no problems with overheating at all. After replacing the radiator the system started heating up (not overheating completely but close once), but only when getting off the freeway. I have replaced the radiator cap, the upper and lower hoses, the thermostat, the clamps on the upper and lower hoses from jesus christ clamps to regular kind, and still heating up. Now during normal in city driving it doesnt heat up like that at all only after being at high rpms. Someone told me a blow head gasket but I have never overheated the car and and it worked fine before I replaced the radiator(of course for the leak). Any ideas?
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Kickjon1985
June 25, 2012.




It ussually does t show signs of over heating at highway speeds. After I get off the highway it will start heating up. Ussually after I get back up to highway speed it cools down, but over the weekend I drove it on the highway, it cooled down after getting back on the freeway but after 5 to 10 miles it warmed up above normal while I was on the freeway.

The radiator is a new one from autozone.


Tiny
Kickjon1985
Jun 26, 2012.
The 98 honda civic only has one cooling fan for the radiator. The other fan is for the airconditioner.


Tiny
Kickjon1985
Jun 26, 2012.
For automatic transmission, they work together.

Have you rechecked the coolant level in the radiator and recovery tank? Do it with cold engine


KHLow2008
Jun 27, 2012.
I did it this morning before I went anywhere. The radiator was full. The recovery was a bit low but I had to go on the freeway a couple days ago and it almost overheated so the radiator was low so it had been sucking it back in the radiator. But the radiator was full this morning.
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Tiny
Kickjon1985
Jun 27, 2012.
As for the fan issue, the 1.6 litre engine has the radiator and the condensor seporated. The radiator is on the left and the condensor is on the right. The oil cooler is part of the radiator. This being said, the fan conected to the condensor doesnt run while the one for the radiator does. I have attached a picture from the mechanic book I have of the engine I have. #12 in the picture is the radiator and the condensor is on the right of it under the silver bracket.


Tiny
Kickjon1985
Jun 27, 2012.
The system we have over here is different. For manual transmission, the radiator would be as you have in your vehicle but for auto transmission, the radiator spans the entire front and the fans works together.

If the radiator is sucking in the coolant from the recovery tank, that could indicate 2 things.
1. There was air in system and and has since self bled. You would need to monitor and see if the overheating occurs again.

2. There is a leak somewhere and it is using up coolant.

Top up the coolant and monitor the situation for another one or 2 times and aleways note the recovery tank level.

When you performed bleeding of the cooling system, did you turn the heater on?


KHLow2008
Jun 27, 2012.
I think that the reason for the coolant level being low is cause the engine got close to over heating the last time I got off the freeway and spewed all the coolant out of the recovery tank on the ground by means of over flowing it. Since then I have filled the radiator, and have been filling the recovery tank slowly to completely fill the system. I have not yet had time, or the money to buy the equipment to pressure test or chemical test the coolant system yet either. One would think that it would be something simple as it worked fine before I changed the radiator. The fan seems to run, but I am curious if its working properly all the time? Is there a way to test this? Or just replace the relay and go from there?


Tiny
Kickjon1985
Jun 28, 2012.
When I got home today from work I poped the hood and checked to see if the fan was working and it seems to be working as it should. The thermostat would close, the fan will come on, then after the fan shuts off the thermostat opens. I checked this by feeling the pressure and temperature of the upper and lower radiator hoses.


Tiny
Kickjon1985
Jun 28, 2012.
Did the engine seem to overheat during this trip?
Is the coolant level correct?


KHLow2008
Jun 28, 2012.
No it didnt, but it seems to be the lenght of the trip on the freeway. The coolant level wasnt low before I left work, but this morning, the coolant recovery tank was low. But I ran it with the heater on to see if maybe it did still have a bubble.


Tiny
Kickjon1985
Jun 28, 2012.

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