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.



Overtorquing can cause the threads to be stripped for this engine and it would depend on the head gasket condition. If problem had been there for quite some time and with steel type gasket, it is not going to help much.

If the overheating occurs under the conditions you mentioned with the fans working continously, I would say the problem is more likely to be cooling efficiency. If the coolant is being sucked back into radiator and with no signs of air trapped in system after engine cools down, that would confirm my suspicions.

However if there are signs of air in system, I would say the head gasket is bad.

KHLow2008
Aug 10, 2012.
Would it be the catalytic converter or muffler?

Tiny
Alik
Aug 11, 2012.
What has the exhaust system got to do with overheating?

KHLow2008
Aug 11, 2012.
Hey KHLow2008,

Recently I have replaced the radiator on my car again, to a oem radiator an replaced all hoses under the hood and the cap. Now I have got pressure in the radiator but, its seams to run over pressure, and it blows all the antifreeze to the overflow. Until it all the coolant is gone the car will run just fine, as soon as it blows all the coolant to the overflow, then it will heat up. It will also not pull the coolant from the overflow to the radiator over night and seems to still have pressure inside the system. I have replaced all parts that can be, does it seem like it just might be a blow head gasket?

Tiny
Kickjon1985
Aug 26, 2012.
Oh and I have conducted 3 block tests on it and the fluid always stays blue. No coolant in the oil, no oil in the coolant, and no white smoke out the exhaust. I have also had someone else start it and smell the exhaust from cold to see if it might be only pulled into the cylinder during a cold engine. But there is no coolant loss, except for what gets boiled over when the overflow fills up all the way.

Tiny
Kickjon1985
Aug 26, 2012.
Too much pressure in system and coolant not being drawn back into system from recovery tank is usually a head gasket problem.

What block test kit did you use? Maybe you should try a different brand to confirm. How much driving time are you able to get before the coolant gets pushed out to the recovery tank? Does the cooling fan run and stop under normal engine operations?

Is the radiator cap good?

KHLow2008
Aug 26, 2012.
The block test is the only tester that is around where I am. Its manufactured by oem. I can get aprox. 30 minutes drive time. This is city driving also, but highway driving I can get only 15 minutes, before the overflow is full and starts to overflow. Yes thefan and everything runs normal alunder normal conditions, it will slowely start to run longer and longer as the radiator runs out of coolant. It stays cool until the system runs low of coolant. The overflow bubbles constantly durring operation in the overflow.

Tiny
Kickjon1985
Aug 26, 2012.
You definitely have a compression leak.
When you remove the head, ensure the head and cylinder face is checked for warping.

KHLow2008
Aug 27, 2012.
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