I have a 97 honda civic ex and just replaced the theromstat because my old one was not opening up. now my car doesnt overheat but if i just let it idle, after it gets to normal operating tempertures the overflow tank will start making noise and steaming and leaking coolant.

I than flushed out my coolant and let the car run at idle and normal operating temp and refilled it tell all air bubbles were gone but after about 2-3mins the coolant slowly rises and flows outta the radiator (this is with the cap off at idle not driving)

i just replaced the head gasket like 2,000miles ago and its on arp head studs and i rechecked and torqued them down and they were all fine. also no oil in the coolant and no coolant in the oil. And this motor has about 2000miles on it . waterpump is not leaking. car will only overheat after a couple drives once the overflow tank steams / leaks all the coolant out...

 

bump...


ordered a new radiator 3 core 2 3/8...

 

its late so most ppl wont answer but it seems you still have air in there somewhere in the system. have u tried bleeding it?

 

what do you mean by bleeding it? that means to drain it all and flush it out pretty much right?

 

works best with two people, basicaly just open one end and pour fluid in the other, to get out all the air bubbles and what not. does that help at all? try you tube it....

 

No. After a cooling system is drained, flushed, and re-filled with new coolant, an air purge (a.k.a. bleed) of the system is done. It is step 10, 11 and 12 at http://media.honda.co.uk/car/owner/m...l/pdf/10-4.pdf . Understand that 40 or so minutes may be required for the cooling fan to come on twice, per step 10. Also in step 10, you can leave the radiator cap off. Alternatively, barely fasten the cap in place such that the system does not become pressurized. It is the low pressure that facilitates the burping of air from the system. Purging the system of air is easily accomplished with just one person.

OTOH, from the extremeness of your Civic's symptoms I suspect another failed head gasket. You do not see oil and coolant mixing--yet--is my suspicion. Did you have the head machined on the head gasket job? Unfortunately if the engine overheated prior to the head gasket job there is a good probability that the head warped and so requires milling to achieve level-ness again.

 

if its a head gasket ill be pissed because its brand new. the head wasnt machined when put back together. it came off a running car with a spun rod. anything else that could be causing this before i have to do all that work

 

Unfortunately heads requiring milling after a head gasket failure are pretty common. Do a compression test to confirm a failed head gasket.

 

did a compression test and its fine its 125 all across (low compression 8.5.1 pistons). checked oil and coolant. got a new radiator. seems fine now. only problem i have is my car will get to the red line temperture wise once we run it 2nd gear to 4th gear on 17psi. i have a block guard so i guess there is nothing i can really do about it

 

Check the thermostat ground and sand it down and make sure its good.

did you properly bleed the coolant this time? Also is the fan comming on?

 

my fan stays on 24/7 i have a switch for it